ORGANIZING INSTITUTIONS: PROGRAM Registration: Sunday 14, 18 - 20 hs Moreno Monday 15 Jardines Américas 08:30 09:00 09:00 09:30 09:30 10:30 10:30 13:00 13:00 14:30 LUNCH BREAK 14:30 15:45 Workshop: "Tectonic evolution of Symposium: "Pine invasion in South Symposium: "Austral insect patterns: Patagonia and adjacent terrains: America: patterns, process, and phylogenetics and biogeography of implications to the early divergence lessons to be learned" austral insects" of the austral biota" Organizers: F. Organizers: M.Nuñez, A. Pauchard & Organizers: P. Cranston, L. Cook, D. Bechis & A. Premoli E. Raffaele Amorim de Souza & S. Trewick 15:45 16:15 16:15 17:15 17:15 17:30 18:00 19:00 19:00 Registration Welcome and Greetings: Dr. G. Stewart, Dr. E. Rapoport and Dr. A. Premoli Special Lecture "The geologic history of Patagonia: Its southern connection through time" by Dr. V. Ramos (Room Américas) Symposium: "Towards a southern synthesis of urban environments: catching up with the north and points of difference" Organizer: G. Stewart COFFEE BREAK Workshop continues Symposium: "Gondwanic connections in Fungi" Organizers: M. B. Pildain & M. Rajchenberg COFFEE BREAK Symposium continues Symposium: "Austral Cenozoic floras and their value in elucidating modern plant distribution" Organizers: M. C. Zamaloa, M. A. Gandolfo & N. R. Cúneo COFFEE BREAK Symposium continues Oral session: Ecology A Special Lecture "Refugia revisited: the behaviour of tropical organisms during glacial-interglacial transitions" by Dr. K. Bennett (Room Américas) Welcome mixer TUESDAY 16 Moreno 09:00 10:30 10:30 11:00 11:00 12:00 12:00 13:00 Jardines COFFEE BREAK Symposium continues 16:00 16:30 16:30 17:00 17:00 18:00 18:00 19:00 19:00 20:00 COFFEE BREAK Symposium continues COFFEE BREAK Symposium continues Patagonia Oral session: Ecology B COFFEE BREAK Oral session: Ecology B Special Lecture "The role of fire in the ecology of southern African grasslands" by Dr. W. Bond (Room Américas) 13:00 14:30 14:30 16:00 Américas Symposium: "Sharing Symposium: Symposium: "Origin and "Palaeoenvironmental changes Gondwanian knowledge and diversification of plants in the experience for capacity building since the Last Glacial Southern Hemisphere: Maximum: patterns, timing and and improvement of regional biogeographical reconstructions and global invasions dynamics throughout the based on molecular management" Organizers: M. F. Southern Hemisphere" phylogenies" Organizers: S. Fontana & M. M. Menvielle, Q. Paynter & A. Organizers: C. Calviño & C. Bianchi Saunders Ezcurra LUNCH BREAK Symposium continues COFFEE BREAK Symposium continues Oral session: Genetics Symposium: "Coniferangiosperms interactions in the Southern Hemisphere" Organizer: P. Bellingham COFFEE BREAK Oral session: Forest ecology Symposium: "Species’ and speciation in the Southern Hemisphere: integrative approaches to studying plant species diversification" Organizers: J. Tate & H. Meudt COFFEE BREAK Symposium continues Oral session: Evolution A Oral session: Ecology B COFFEE BREAK Oral session: Conservation Special Lecture "The flora of New Caledonia: state of our knowledge and perspectives" by Dr. J. Munzinger (Room Américas) Poster session (Ecology and Conservation) and complimentary wine (Room Patagonia) WEDNESDAY 17 Moreno 09:00 10:30 11:00 13:00 13:00 14:30 14:30 16:00 18:00 19:00 Américas Patagonia 10:30 Symposium: "Progress with Symposium: "Physiological Symposium: "Controversies conservation and adaptations in the Southern in the Quaternary of the sustainable management of Hemisphere: are there Southern Hemisphere" the Southern Hemisphere's convergences among Organizers: J.-B. W. Stuut, Oral session: Biogeography indigenous temperate Gondwanian land masses in & Peter Kershaw grasslands: developing a cold-blooded vertebrates?" strategic plan" Organizers: Organizer: N. Ibargüengoytía A. Mark, K. Dickinson & A. Michelson 11:00 COFFEE BREAK COFFEE BREAK COFFEE BREAK COFFEE BREAK 12:00 Symposium continues Symposium continues Symposium continues Oral session: Biogeography 12:00 16:00 16:30 17:15 Jardines 16:30 17:15 18:00 Special Lecture "Invasive species and global change: novel ecosystems and their implications for conservation and restoration" by Dr. R. Hobbs (Room Américas) LUNCH BREAK Symposium continues COFFEE BREAK Symposium continues Symposium: "Plant ecological genetic insights in the southern hemisphere" Organizers: M. C. Acosta, M. Arbetman, P. Mathiasen, P. Quiroga, A. Premoli & C. Souto COFFEE BREAK Symposium continues Symposium continues Oral session: Biogeography Oral session: Evolution COFFEE BREAK COFFEE BREAK Symposium continues Oral session: Palaeobiology Oral session: Palaeobiology A B 19:00 Special Lecture "Using studies of gene expression to investigate species radiations in the New Zealand alpine flora" by Dr. C. Voelckel (Room Américas) Poster session (Palaeobiology, Biogeography, Evolution, Genetics, and Geology) and 20:00 SC Council Meeting complimentary wine (Room Patagonia) THURSDAY 18 Moreno 09:00 Jardines Américas 10:30 Symposium: "Phylogeography and Symposium: "Ecology, speciation in Patagonia: a management and conservation of common perspective across austral cool-temperate forests: the taxa?" Organizer: D. Ruzzante role of long-term research sites" Organizers: G. Martínez Pastur & C. B. Anderson 11:00 COFFEE BREAK COFFEE BREAK 12:00 Symposium continues Symposium continues Symposium: "Raising Zealandia: biogeography of a sunken continent" Organizers: S. Trewick & A. Paterson Symposium continues 16:30 16:00 Symposium: "Insights on Southern Symposium: Hemisphere plant species "The future of disturbance ecology" richness, endemism and Organizers: L. Walker, & M. colonization" Organizers: M. Oesterheld Gandolfo, & M. Kalin-Arroyo 16:30 COFFEE BREAK COFFEE BREAK 17:15 Symposium continues Symposium continues 17:15 18:00 10:30 11:00 12:00 13:00 14:30 16:00 18:00 20:00 COFFEE BREAK Symposium: "Origin and diversification of the New Caledonian biota" Organizers: U. Swenson & P. P. Lowry 13:00 Special Lecture "A high-resolution multiproxy approach to reconstruct centennial changes in the Antarctic Oscillation" by Dr. R. Villalba (Room Américas) 14:30 LUNCH BREAK COFFEE BREAK Symposium continues Oral session: Geology 19:00 Special Lecture "Towards a holistic view of understanding behavioural and energetic options of seabirds in southern oceans" by Dr. R. Wilson (Room América) SC BANQUET followed by PARTY!!!!! (Room Patagonia) ABSTRACTS Conferences Refugia revisited: the behaviour of tropical organisms during glacial-interglacial transitions BENNETT K.* Queen's University, Belfast, UK *k.d.bennett@qub.ac.uk Patterns of endemism in the Neotropics have been explained by restriction of forest to `refugia' in arid cold-stages of the Quaternary (Haffer 1969). The palaeoecological record, however, shows no such forest contraction. I review palaeoecological and phylogenetic data on the response of Neotropical taxa and communities to climatic changes of the Cenozoic. Solar insolation varies over this period with latitude and geography, including shifts in opposite directions between high and low latitudes. In the Neotropics, distribution and abundance patterns originate on a wide range of timescales through the Cenozoic, down to the currently dominant precession forcing (20 kyr). In contrast, distributions and abundances at higher latitudes are controlled by obliquity forcing (40 kyr). The patterns observed by Haffer (1969) are likely derived from pre-Quaternary radiations and are not inconsistent with palaeoecological findings of continuous forest cover in major areas of the Neotropics during the Quaternary. The relative proportions of speciation processes have changed through time between predominantly sympatric to predominantly allopatric depending on the prevailing characteristics of orbitally-forced climatic changes. Behaviour of Neotropical organisms and ecosystems on long timescales may be influenced much more by precessional forcing than by the obliquity forcing that controls high latitude climate change and glaciations. 'Open' ecosystems: globally important, poorly understood BOND W.* University of Cape Town, South Africa *William.bond@uct.ac.za 'Open' ecosystems include grasslands, savannas and shrublands where tree cover is too sparse to exclude shade-intolerant plants. They are usually assumed to be the natural vegetation in areas that are too cold or too arid for trees. However open ecosystems also occur over vast areas of the world where the climate is warm enough and wet enough to support closed forests. Though commonly attributed to human disturbance and deforestation, open ecosystems include regions with very diverse biotas specialised for open habitats implying a long evolutionary history. On shorter time scales, palaeoecological studies have shown that forests are often the younger vegetation ousting ancient grasslands. A fresh approach to the ecology, biogeography and evolution of open ecosystems is beginning to emerge. It raises new questions on interpreting the past and in predicting the future of ecosystems not closely coupled to climate. Invasive species and global change: novel ecosystems and their implications for conservation and restoration HOBBS R.* University of Western Australia, Australia *rhobbs@cyllene.uwa.edu.au Changes in climate and other environmental conditions are combining with changes in species distributions and combinations to create entirely new environmental domains and ecological communities. Hence we are increasingly experiencing climatic and disturbance events outwith the historic range and observing increasing evidence of novel biotic assemblages and interactions which behave in unpredictable ways. We are only just becoming aware of the implications of this for ecosystem management and policy. I discuss these phenomena, drawing on examples from Australia and elsewhere, and explore the need for radically different approaches to management and policy in the future. The flora of New Caledonia: state of our knowledge and perspectives MUNZINGER J.* Laboratoire de Botanique et d'Ecologie Appliquées, Herbarium Nou, New Caledonia *jerome.munzinger@noumea.ird.nc New Caledonia, a French overseas territory located ca. 1600 km E of Queensland (Australia), is famous worldwide for its very diverse flora, with ca. 3300 native species (75% endemic) and 5 (or perhaps 3) endemic families. The flora is also fascinating because of the large number of old lineages, such as Annonaceae, Araucariaceae, Chloranthaceae, Lauraceae, Monimiaceae, Nothofagaceae, Proteaceae, Trimeniaceae, Winteraceae, and of course the famous Amborella trichopoda, the most basal extant angiosperm. But New Caledonia's flora, long recognized as remarkable by botanists, remains incompletely known, and every year new species (sometimes new genera) are described, not only from previously collected specimens in herbaria, but also from plants discovered in the field. Significant gaps also exist in taxonomic work, a fact that is especially important when threats on remaining natural areas are growing in what is the world's smallest biodiveristy "hotspot". Using our herbarium database, we show that 10% of the flora is represented in Noumea's herbarium by a single collection and 25% by only 3 collections, and that 60% of the territory has a collection density of <100 specimens per 100km2, the minimum acceptable. A global state of our knowledge is presented, and future prospects and needs are discussed. The geologic history of Patagonia: Its southern connection through time RAMOS V.A.*; FOLGUERA A. and GHIGLIONE M. Universidad de Buenos Aires, Argentina *andes@gl.fcen.uba.ar Patagonia, one of the less populated areas of South America, and a vast semidesert land, was the inspiration for many unusual hypotheses on its geologic origin. However, based on modern plate tectonic concepts the history of Patagonia records a complex interaction with the Gondwana supercontinent and striking connections with the present southern continental masses. Patagonia together with the Antarctic Peninsula and some other minor crustal blocks participated in the amalgamation of Gondwana during the Brasiliano-Panafrican orogeny (~ 530 Ma). Sooner after the amalgamation with Gondwana, subsequent rifting led to the isolation of Patagonia during most of the Paleozoic times. An important collision with the Antarctic Peninsula at about 280 Ma marked the new cycle of amalgamation in the latest Carboniferous times. By the end of the Paleozoic had one of the stronger connections with the Antarctic and other austral land-masses. Subsequent re-amalgamation with Gondwana at 280 Ma, gave the present location to Patagonia. Its southern connection lasted until Middle Jurassic times when near 160 Ma, during the early opening of the Weddell Sea, Antarctica start rifting away. However, final disconnection took place near 30 Ma, when the Drake Passage opened and the circumpolar currents were developed. Collisions along the Pacific side triggered Cordillera uplift and early glaciations at ~ 6 Ma. A high-resolution multiproxy approach to reconstruct centennial changes in the Antarctic Oscillation VILLALBA R.* (1); LARA A. (2); MASIOKAS M. (1); COOK E. (3) and SCHNEIDER D. (4) (1) IANIGLA-CONICET, Argentina (2) Fac. Ciencias Forestales, Univ. Austral, Chile (3) LDEO, Columbia University, USA (4) Earth-Space Science, University of Washington, USA *ricardo@mendoza-conicet.gov.ar The Antarctic Oscillation (AAO) is the dominant pattern of climate variability at mid- to high-latitudes in the Southern Hemisphere (SH). AAO anomalies are related to climate changes over Antarctica and temperate regions of South America, New Zealand, Australia and South Africa. The positive phase of the AAO is associated with a cooling across E Antarctica and central Australia, and a warming over the Antarctic Peninsula, S Patagonia, Tasmania and S New Zealand. This positive phase is also related to anomalously dry conditions over SW South America, New Zealand and Tasmania and to wet conditions over much of Australia and South Africa. A high-resolution proxy network from mid- to high-latitudes in the SH was used to reconstruct past variations in the AAO. 338 tree-ring chronologies from the Andes, New Zealand, and Tasmania, were grouped into regional records. Tree-ring records were complemented with five, annually-resolved, ice cores from Antarctica. The reconstructions explain between 51% (Annual) and 57% (October-March) of the total variance in the instrumental AAO in the interval 1949-2001. Consistent with observational records, most reconstructions show a positive trend in the AAO during the past 50 years, suggesting significant changes in the atmospheric circulation in the SH. Persistent trends in the AAO may increase the severity of climatic anomalies with implications for the conservation of natural resources and the functioning of ecosystem services in the SH. Using studies of gene expression to investigate species radiations in the New Zealand alpine flora VOELCKEL C. (2); HEENAN P. (3) and LOCKHART P.* (1) (1) Allan Wilson Center for Molecular Ecology and Evolution, Massey University, New Zealand (2) Allan Wilson Center for Molecular Ecology and Evol (3) Landcare Research, Lincoln, New Zealand *p.j.lockhart@massey.ac.nz Gene expression profiling provides a means for predicting ecophysiological differences that have evolved in closely related species. For this purpose we have recently initiated heterologous microarray and mRNA sequencing studies (using Illumina GAII technology) on the New Zealand alpine Pachycladon (Brassicaceae) - an allopolyploid plant group of 9-10 species largely restricted to the New Zealand Southern alps. We seek to understand the ecological drivers of species diversification and have used high throughput mass spectrophotometry and HPLC analyses to test and validate our findings from gene expression profiling. We discuss our finding that plant-pathogen/herbivore interactions appear as important as abiotic interactions in shaping the diversity of Pachycladon. Our results suggest that even with non-model allopolyploid systems, mRNA sequencing provides a means of significantly advancing understanding of the processes important in species radiation and adaptive diversification. Towards a holistic view of understanding behavioural and energetic options of seabirds in southern oceans. WILSON R.* Swansea University, Wales UK *r.p.wilson@swansea.ac.uk Seabirds are warm-blooded major top predators in the world's oceans, foraging in a cold, dense, physiologically hostile environment for mobile, sub-surface prey that is patchily distributed in both horizontal and vertical dimensions. The remarkable success of seabirds, despite this, is due to a suite a physiological, behavioural and energetic strategies, many of which are only now becoming apparent. This work looks at some new techniques for studying seabirds at sea using animal-attached devices and reports on some of the communalities that birds have manifest as solutions for maximizing their foraging success in this seemingly bird-unfriendly habitat. Symposia Plant ecological genetic insights in the southern hemisphere. Differentiation and Diversification in New Caledonian Araucaria HOLLINGSWORTH P.* Royal Botanic Garden Edinburgh *P.Hollingsworth@rbge.org.uk The genus Araucaria is widely distributed in the Southern hemisphere with extant species occurring in South America, Australia, New Caledonia, Norfolk Island and New Guinea. The highest diversity of species is in New Caledonia, where 13 of the world’s 19 species are endemic. These New Caledonian species form a monophyletic group, suggesting a remarkable in situ diversification of wind-pollinated trees in a small land area. To understand the evolutionary history of these species, and the contemporary threats posed by landscape degradation, we have used genetic markers to (a) estimate the timing of species diversification, (b) undertake phylogeographic investigations of range-wide genetic structure to establish the scales over which populations become differentiated in New Caledonia, and (c) examine patterns of population differentiation within individual species. The findings of these studies will be discussed in terms of the evolution and conservation of Araucaria in New Caledonia. Evolutionary genetic studies in the Tasmanian species of Eucalyptus VAILLANCOURT R.E.*; MCKINNON G.E.; JONES R.C.; STEANE D.A.; HUDSON C.J. and POTTS B.M. School of Plant Science and Cooperative Research Centre for Forestry, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia *R.Vaillancourt@utas.edu.au The biogeographic pattern of chloroplast DNA (cpDNA) variation in Eucalyptus on the island of Tasmania in Australia, is consistent with reticulate evolution involving at least 12 species from the subgenus Symphyomyrtus and also coincides with putative locations of glacial refugia in coastal areas. To distinguish between interspecific hybridization and lineage sorting as the cause of reticulate evolution, a fine-scale cpDNA phylogeographic study was undertaken. The genealogy and distribution of chloroplast haplotypes suggest that the abundant E. globulus has acquired cpDNA haplotypes, including rare ones, through hybridisation from E. cordata (a rare sympatric congener) in at least four different mixed populations. In a follow-up study, AFLP markers were used to study the pattern of nuclear gene introgression from E. cordata into E. globulus. We show that introgression of AFLP markers occurs in mixed populations, although overall both E. globulus and E. cordata retain strongly differentiated nuclear gene pools. Based on the observations that introgression appears to be more common with cpDNA than nuclear AFLP markers and that the frequency of E. cordata AFLP markers in E. globulus departs from their frequency in E. cordata, it appears that selection may be controlling the introgression process. This hypothesis is being studied using a newly developed array of high-throughput DArT markers, which have known sequences and can be mapped on the Eucalyptus genome. Forest fires reset genetic structure of seeders and preserve that of sprouters, evidence in South American Nothofagus PREMOLI A.C.*; MATHIASEN P. and KITZBERGER T. Universidad Nacional del Comahue - INIBIOMA *andrea.premoli@gmail.com In northern Patagonia, Nothofagus species are dominant components along west-to-east precipitation gradients where fire is the predominant coarse-scale disturbance. We tested the hypothesis that genetic consequences of fire i.e. levels of diversity and spatial distribution of genotypes, vary in Nothofagus according to specific life history traits. We followed a spatially explicit sampling design to collect leaf tissue for genetic analyses using nuclear markers on mature and postfire forest stands of obligate seeders (high-elevation dry N. pumilio and low-elevation mesic N. dombeyi) and the resprouter N. antarctica. Postfire even-aged stands of obligate seeders held relatively reduced polymorphism due to drift as few remnant trees recolonize burned sites. Also a uniform spatial distribution of genotypes resulted from synchronic establishment of closely related progeny produced during masting after fire. In contrast, mature stands of seeders undergoing gap-phase regeneration yielded increased genetic diversity and a significant clustering of genotypes at short spatial scales as a result of distinct mother trees contributing to local establishment. On the other hand, sprouting after fire preserved diversity and complexity. Given that fire frequency is expected to increase under warming scenarios, actions should be taken to facilitate postfire establishment of seeders such as passive restoration of N. pumilio drylands and exclosure of herbivores within burned N. dombeyi forests. Genetic consequences of habitat fragmentation in plant populations: global and southern patterns AGUILAR R.* (1); QUESADA M. (2) and ASHWORTH L. (1) (1) Universidad Nacional de Cordoba - IMBIV (2) Universidad Nacional Autonoma de Mexico - CIEco *rams.aguilar@gmail.com The loss and fragmentation of habitats by human activities are pervasive phenomena in terrestrial ecosystems and the main current driving forces behind biodiversity loss. Much research has been conducted worldwide to evaluate fragmentation effects on plant population genetic parameters. We quantitatively reviewed the results of fragmentation studies to test the general hypothesis that fragmentation affects the genetic diversity of plant populations. We also assessed whether fragmentation has differential effects depending on certain life history and ecological traits of plants, and tested whether particular methodological approaches influence the ability to detect genetic erosion in fragmentation studies. Overall, genetic diversity and outcrossing rates of plants decreased in fragmented habitats. Outcrossing and either common or recently rare plants showed strongest negative effects on their genetic diversity. Higher inbreeding coefficients were only observed in studies analyzing progenies in fragmented habitats. Finally, the time elapsed in fragmentation conditions significantly influenced the magnitude of effects. Results suggest that fragmentation is shifting mating patterns towards increased selfing. Remarkably, only 20% of the studies were conducted in the Southern Hemisphere (SH). Although main general response patterns remain similar within this set of studies, I will discuss some particular trends observed in species from the SH and compare them with global patterns. Molecular diversity analysis of cpDNA haplotypes: Cryptic apecies in the Australian orchid genus Chiloglottis SMOUSE P. (1) and PEAKALL R.* (2) (1) Rutgers University (2) Australian National University *smouse@aesop.rutgers.edu There is a growing need for treatments of genetic diversity that use metrics of genetic uniqueness and sharing, rather than partitions of genetic variance. Using a Shannon information analysis, we assayed chloroplast DNA diversity for a pair of cryptic sister taxa in the Australian orchid genus Chiloglottis. The orchids sexually lure male wasps (Neozeloboria) by mimicking species-specific female wasp pheromones. We might anticipate that pollinator-mediated reproductive isolation should develop rapidly between orchids pollinated by different wasps, accompanied by only subtle genetic divergence, for genes not involved in the production of the wasp attractant. Using a set of 21 indels and 41 SSRs from cpDNA, we characterized N = 553 samples of sister taxa in the C. valida complex (Cval-1 and Cval-2) that can only be distinguished by the chemical cues they use to attract their respective (N. monticola & N. impatiens) pollinators. We calculated indel diversity indices within both taxa (D1 = 2.64 and D2 = 2.61) and a proportional divergence index of (ƒ´12 = 0.139), showing substantial haplotypic overlap of the taxa. If we include the more subtle SSR markers, we obtained (D1 = 59.25, D2 = 78.25, and ƒ´12 = 0.923), showing almost no sharing of cpDNA-lineages. Reproductive isolation and genetic divergence are almost complete, though morphological separation is still negligible. These new methods can be expected to improve genetic diversity resolution for cryptic taxa. Phylogenetic study of frugivore incidence in fruit evolution in Ficus LOMASCOLO S.B.* (1); LEVEY D.J. (2); KIMBALL R.T. (2); BOLKER B.M. (2) and ALBORN H.T. (3) (1) IADIZA, CCT Mendoza, CONICET and Department of Zoology, University of Florida. (2) Department of Zoology, University of Florida (3) Center for Medical, Agricultural, and Veterinary Entomology, USDA *slomascolo@mendoza-conicet.gov.ar Even though plant reproduction largely depends on seed dispersal, evolutionary ecologists have been unable to link co-occurring fruit traits with differences in behavior and morphology of fruit-eating vertebrates. Hence, fruit diversity remains largely unexplained. Using a multivariate phylogenetic comparative test with unbiased estimates of fruit odor and color, we demonstrate for the first time that fruit traits evolve in concert and as predicted by differences in the behavior and morphology of their frugivorous seed dispersers. Observations at fruiting trees independently confirmed that differences in fig traits predict differences in dispersers. Taken together, these results demonstrate that differences among frugivores have shaped the evolution of fruit traits. More broadly, our results underscore the importance of mutualisms in both generating and maintaining biodiversity. Spatial and genetic differentiation of two broadly distributed acacias and their rhizobial symbionts BROADHURST L.*; THRALL P.; HOQUE S. and YOUNG A. CSIRO Plant Industry *Linda.Broadhurst@csiro.au Shrubby legumes are an important component of almost all Australian ecosystems. Leguminous species have important symbiotic associations with nitrogen-fixing bacteria, but despite this, little is known regarding the scale and importance of this interaction. Understanding this interaction has importance consequences for the restoration of both above- and below-ground biodiversity. This research assessed the population genetic structure of Acacia salicina and A. stenophylla, two host species broadly distributed across eastern Australia, and, the spatial distribution, abundance and effectiveness of their associated symbiotic bacteria. Little genetic structure existed among A. salicina populations whereas a division between north-western and south-eastern A. stenophylla populations was evident. There was also no apparent geographic distribution among symbionts isolated from A. salicina whereas a shift from Rhizobium to Sinorhizobium was seen in the south-west of the A. stenophylla distribution. Glasshouse studies indicated that while A. salicina plants grew equally well when planted in soil collected from beneath either host, A. stenophylla plants grew much better in their own soil. Overall, these results indicate that there can be significant differences in the specificity of symbiont associations, even for closely related hosts, and that geographic distribution does not necessarily predict genetic structure of either the host or their associated symbionts. Conifer-angiosperm interactions Conifer-angiosperm interactions in New Zealand: using historical data to redress modern biases MCGLONE M.* and RICHARDSON S. Landcare Research, Lincoln, New Zealand *mcglonem@landcareresearch.co.nz Highly oceanic environments and derivation from warm temperate to subtropical antecedents, has resulted in unusual forest flora adaptations and vegetation types in NZ. Relative to other temperate regions, NZ has a large number of small, evergreen, subcanopy trees and shrubs and relatively few canopy and emergent trees which often have unusually small leaves. NZ conifers are mainly slow-growing, long-lived, small-leaved emergents and poor competitors with the abundant understorey angiosperms but, once established, are resistant to a wide range of stresses. This leads to paradoxical outcomes. In the Northern Hemisphere, cold-tolerant conifers dominate alpine forests. In NZ, evergreen angiosperms (mainly Nothofagus), dominate despite conifers having the most frost-tolerant species in the flora, as cold-resistance is of minor importance relative to growth adaptations to cool summers. In the Southern Hemisphere, podocarps are largely taxa of mild, moist or tropical montane climates: NZ podocarps are abundant under dry, summer-warm/winter-cold climates because angiosperm competitors cannot suppress conifer regeneration in stressed but fire-free environments. Our ecological understanding of conifer-angiosperm relationships is distorted because most surviving forests are cool and moist due to deforestation of lowland and drier regions. We suggest a focus on forests of cold, and drought stressed climates and more attention to historical factors are necessary to develop a full picture. Demography of New Caledonian Araucariaceae: Doing better than expected? ENRIGHT N.* (1) and RIGG L. (2) (1) Murdoch University (2) Northern Illinois University *N.Enright@murdoch.edu.au Tropical and sub-tropical coniferous tree species are generally regarded as strongly competitive with angiosperm trees only in habitats that limit angiosperm growth. The population dynamics of three New Caledonian Araucariaceae (Araucaria laubenfelsii, A. muelleri and Agathis ovata) are analysed for habitats ranging from lateritic boulder-fields through fire-induced shrublands to mature rainforest. While all habitats are located on ultramafic substrates that provide challenging soil chemical conditions for plant growth, they support a high diversity of angiosperm tree species and offer a range of stress and disturbance levels to which plants must respond. We hypothesised that the conifer species would be increasingly disadvantaged relative to angiosperms along the gradient from boulder-field to rainforest, reflecting a gradient of increasing nutrient resource, but decreasing light, availability. Estimated rates for population growth show that the conifer species are able to maintain population sizes across the full range of vegetation types and disturbance regimes investigated, with potential population growth rates highest at intermediate levels of disturbance/stress. Results are considered in relation to the distribution and growth of angiosperm tree species across this same gradient of habitat types. Do conifer and angiosperms regenerate in different habitats along resource gradients in New Zealand rain forests? BELLINGHAN P. (1); BURSLEM D. (2) and RICHARDSON S.* (1) (1) Landcare Research (2) University of Aberdeen *bellinghamp@landcareresearch.co.nz In many southern hemisphere rain forests, angiosperm and conifers often coexist. Angiosperms are often short-lived and conifers are often long-lived, and along resource gradients, angiosperms are generally thought dominate resource-rich sites and conifers on less productive sites. In this study we report differences in the early stages of regeneration (seedlings 0.15 – 1.35 m tall) of six angiosperm trees and three conifers along resource gradients in a warm temperate rain forest in northern New Zealand. We quantified seedling densities along toposequences from ridges to faces to gullies, along which total soil carbon varied 13-fold, total soil nitrogen varied 6-fold and total soil phosphorus varied 9-fold. We quantified light environments along these toposequences and these varied nearly 10-fold (from 1.6 to 12.7% canopy openness). Seedlings are tagged to determine their onward growth and survival over the next three years, and seedlings of the same species are being grown in experimental conditions manipulating forest soils and light environments. Soil development and conifer-angiosperm interactions TURNER B.* (1); CONDRON L. (2) and DALLING J. (3) (1) Smithsonian Tropical Research Institute, Panama (2) Lincoln University, New Zealand (3) University of Illinois, USA *TurnerBL@si.edu We present two case studies in which soil nutrient status exerts a strong control on the distribution of angiosperms and conifers in temperate and tropical rain forests. In temperate rain forest in New Zealand, a decline in soil phosphorus associated with long-term ecosystem development corresponds with a shift in dominance from evergreen angiosperms in the early stages of the sequence characterized by nitrogen limitation, to conifers of the Podocarpaceae in the late stages of the sequence characterized by phosphorus limitation. In lower montane rain forest in western Panama, podocarps occur only on extremely infertile soils developed on rhyolitic parent material, but are absent on more widespread and nutrient-rich soils developed on andesite and granodiorite. In New Zealand, the decline in soil phosphorus is associated with an increase in the activity of phosphatase enzymes and marked changes in the soil organic phosphorus composition, including the depletion of recalcitrant compounds such as the inositol phosphates. Podocarps growing on phosphorus-poor soils may therefore be adapted to acquire phosphorus from stable organic forms, perhaps through their conspicuous root nodules, which do not fix nitrogen, but contain arbuscular mycorrhizal fungi. Finally, data will be presented from recent studies of a Holocene chronosequence of well-drained sandy soils, which is dominated by the podocarps in the early stages of ecosystem development. Origin and diversification of plants in the Southern Hemisphere: biogeographical reconstructions based on molecular phylogenies Cladistic biogeography, molecular dating, fossils and the Proteaceae WESTON P.* (1); SAUQUET H. (2); MAST A. (3) and BARKER N. (4) (1) National Herbarium of New South Wales, Australia (2) Université Paris-Sud, Orsay, France (3) Florida State University, Tallahassee, USA (4) Rhodes University, Grahamstown, South Africa *peter.weston@rbgsyd.nsw.gov.au Objectives Cladistic biogeographic analyses of the Proteaceae have found significant congruence between biological and geological area cladograms, consistent with diversification of the family prior to Gondwanic fragmentation. Molecular dating analyses have suggested on the contrary that most clades showing trans-oceanic disjunctions are too young to have achieved their distributions as a result of continental drift. Methods The phylogeny of the Proteaceae was reconstructed using morphological characters and alignments of eight nuclear and chloroplast loci. Clade ages were estimated using three different relaxed clock dating methods and fossil and geological age constraints. Cladistic biogeographic patterns were reconstructed using event-based tree-fitting methods. Results A highly resolved phylogeny was produced. The age of the Proteaceae crown group was estimated as mid-Cretaceous using fossil age constraints and from mid Cretaceous to Archaean using geological age constraints. Cladistic biogeographic reconstructions of the whole family were incongruent with known geological relationships but those based on some subsets of clades were congruent with geology under some assumptions. We found significant correlation between the evolution of late fruit dehiscence and geographic range shifts in the Macadamieae. Conclusions The distribution of the Proteaceae has resulted from a combination of processes of biotic dispersal, extinction, vicariance and long distance dispersal. Evolution and biogeography of the austral Loliinae (Poaceae) and Dioscoreaceae CATALAN P.* University of Zaragoza *pcatalan@unizar.es Phylogenetic and historical distribution reconstructions, based on analysis of plastid and nuclear sequence data, of two monocotyledoneous plant groups, the temperate Loliinae grasses and the tropical and subtropical yams, will be presented. The origins and radiations of the polyploid austral Loliinae grasses will be related to those of their more ancestral diploid northern hemisphere counterparts. The evolutionary trends of the austral Dioscoreaceae lineages will be compared with those of other boreal yam lineages. Dating analysis based on relaxed molecular clock methods and fossil calibrations indicate a late Tertiary – to – early Quaternary time span for the main divergences of the different lineages of these two groups that show different ecological adaptations. Biogeographical trends of the southern branches of temperate grasses and yams indicate the existence of long dispersal events in both intracontinental and intercontinental migrations and the occurrence of some vicariance events. Long-distance American-African and American-New Zealand connections might have shaped the biogeography of some Loliinae groups. Origins and diversification of New Zealand Alpine Ranunculus LEHNEBACH C.* (1); JOLY S. (2); BECKER M. (3) and LOCKHART P. (3) (1) Te Papa Mueseum, Wellington (2) McGill University, Montreal (3) Allan Wilson Centre, Massey University,New Zealand *p.j.lockhart@massey.ac.nz The alpine Ranunculus are regarded as a classic example of adaptive radiation in New Zealand (Fisher 1965). Molecular phylogenetic analyses indicate that this monophyletic group of 16-20 morphologically and ecologically distinct species arrived in New Zealand by transoceanic dispersal in the Late Tertiary and radiated into a diversity of habitats formed by Pliocene-Pleistocene mountain building and glacial-interglacial cycles. Species exhibit a range of reproductive compatibilities and patterns of morphological variation in nature consistent with a range of hybrid relationships. In this talk we discuss biogeographic origins and the difficulty of species delimitation for the New Zealand alpine species, the development of genome wide markers obtained using Illumina GAII sequencing technology, as well as phylogenetic (splits graph and coalescent) analyses that seek to test the extent and evolutionary significance of hybridization in the group. Phylogeny and Biogeography in Solanaceae, Verbenaceae, and Bignoniaceae: A Central Role for Southern South America as a Source of Diversity OLMSTEAD R.* University of Washington *olmstead@u.washington.edu Recent molecular phylogenetic studies of Solanales and Lamiales show that Solanaceae, Verbenaceae, and Bignoniaceae all diversified in South America. Estimated dates for the stem lineages of all three clades imply origins in late Cretaceous (or earlier), at which time the present continents had separated from the united Gondwanan continent. In each clade, several lineages are represented in Africa, Asia, and North America. In most cases, the position of lineages of Old World plants on their respective phylogenies suggests much younger origins for these lineages, implying long-distance dispersal as the primary mechanism leading to contemporary distributions. Detailed phylogenetic hypotheses for these clades permit explicit enumeration of the number of events leading to the extant distributions. Resolution among major clades of Lamiales makes it difficult to establish sister groups for Bignoniaceae and Verbenaceae, but a well-resolved phylogenetic hypothesis for Solanales implies that the origin of Solanaceae may have predated the breakup of Gondwana and that extinction may be responsible for the near absence of Old World lineages among the extant early diverging lineages of Solanaceae. Southern patterns in the origins of the dicot order Apiales (Apiaceae, Araliaceae, and related families) PLUNKETT G.M.* and NICOLAS A.N. The New York Botanical Garden *gplunkett@nybg.org Apiales are most speciose in North Temperate zones, but previous phylogenetic studies suggest that its origins are southern. We tested these suggestions at three levels of phylogeny, constructing new datasets using plastid DNA sequences (trnD-trnT and rpl16-intron). We estimated the timing of major diversification events using BEAST with fossil calibrations, and the geographic patterns using Lagrange and DIVA. At the deepest levels, our results are consistent with Gondwanan vicariance, giving rise to Griseliniaceae, Torricelliaceae, and the rest of the order (=suborder Apiineae), originating at a median minimum age of ~100 mya. However, disjunct patterns in Griseliniaceae between New Zealand and South America appear to be due to much more recent dispersal. Apiineae include four major clades (Pittosporaceae, Araliaceae, Myodocarpaceae, and Apiaceae), each of which has an Australasian origin (dating from ~94-68 mya). Within Apiaceae, the geographic pattern among the major clades (Australasia, South America, and Africa) is consistent with Gondwanan vicariance, but the timing of these origins (~83-68 mya) is not. Instead, dispersal is more likely, during a period after the continents had separated but were still in relatively close proximity. Mackinlayoideae originated in the ancestral area (Australasia), but a dispersal to South America explains the origin of Azorelloideae, and a dispersal to Africa (possibly through South America) is most likely for Saniculoideae+Apioideae. Systematics of Apiaceae subfamilies Apioideae and Saniculoideae: phylogenetic affinities and biogeographic implications CALVIñO C.* (1) and DOWNIE S. (2) (1) INIBIOMA -Conicet-Universidad Nacional del Comahue (2) University of Illinois at Urbana-Champaign *ccalvino@crub.uncoma.edu.ar Only 30% of Apiaceae genera belong to the southern hemisphere (SH), but the region is important because it is the origin of this mostly north temperate family. Four subfamilies are currently recognized within Apiaceae: Apioideae, Saniculoideae, Azorelloideae and Mackinlayoideae. While Azorelloideae is mostly South American and Mackinlayoideae is mostly Australian, Apioideae and Saniculoideae are mostly north temperate taxa. The origin of Azorelloideae and Mackinlayoideae in the SH is evident. We review our work to highlight the importance of the SH in the origin of subfamilies Apioideae and Saniculoideae, as well. To estimate phylogeny among these subfamilies cpDNA trnQ-trnK and nrITS regions from 241 accessions were analyzed using maximum parsimony and Bayesian methods. The resultant phylogenies were examined using dispersal-vicariance analysis to ascertain the biogeographic histories of these taxa. The majority of the southern African endemic genera comprise successively diverging lineages at the base of both Apioideae and Saniculoideae. The biogeographic scenarios reinforce the importance of southern Africa in the early evolutionary history of Apiaceae. This region is the origin of the common ancestor of subfamilies Apioideae and Saniculoideae and also the place where these two major lineages diverged. Subfamily Apioideae subsequently migrated northward into Eurasia. Within subfamily Saniculoideae, tribe Saniculeae, also subsequently migrated northward into Asia or Europe. Austral insect patterns: phylogenetics and biogeography of austral insects Better the weta you know: biogeography of southern orthoptera TREWICK S.* (1); MORGAN-RICHARDS M. (1); GOLDBERG J. (1); PRATT R. (1) and JOHNS P. (2) (1) Massey University (2) Canterbury Museum *s.trewick@massey.ac.nz We consider austral entomology from the perspective of New Zealand Orthoptera. We start by considering the composition of the NZ orthopteran fauna; the relative diversity of families, noting those with little or no representation. The two most important families of ensifera are Rhaphidophoridae (cave weta, cave crickets or camel crickets), and Anostostomatidae (weta, king crickets). These two families dominate NZ orthopteran diversity and ecologically prominent. The rhapidophorids and anostostomatids are biogeographically different, the former with near global distribution and the latter largely confined to the southern hemisphere. The presence of anostostomatids in southern India adds to the impression of a gondwanan distribution, but species are also in Japan. In the NZ region though, these two families are not consistently represented; no rhaphidophorids in New Caledonia and rather few in Australia. Anostostomatids however, have endemic genera in both those countries in addition to New Zealand. Our phylogenetic analyses have contributed to understanding of systematics and biogeography in New Zealand and from there we have expanded sampling to include most regions where anostostomatids occur. The fauna of NZ appears to be comparatively rich at deeper levels compared to Australia and New Caledonia, but analysis with South American and African taxa reveals a major split in the family. We emphasise the influence of taxon/region sampling on biogeogaphic/evolutionary inference. Biogeography and diversification of colletid bees: Emerging patterns from the Southern End of World ALMEIDA E.* (1); PIE M. (2); BRADY S. (3) and DANFORTH B. (4) (1) Universidade Federal do ABC (2) Universidade Federal do Parana (3) National Museum of Natural History (Smithsonian) (4) Cornell University *eduardo.almeida@ufabc.edu.br Phylogenetic research coupled with biogeographical inference provides the ideal analytical framework to study groups of organisms with an austral distribution. With these tools, vicariance patterns shaped by the breakup history of Gondwana can be distinguished from events such as dispersal. Present distribution of colletid bees strongly suggests a historical connection to the three major southern continents currently vegetated: Australia, South America, and Africa. The colletid fossil record is insufficient to elucidate the historical processes that could have lead to the present-day distribution of these bees. We present results of a biogeographical investigation using DIVA (Dispersal-Vicariance Analysis) in addition to a Bayesian dating analysis based on a relaxed molecular clock. The biogeographical scenario for the early diversification of Colletidae is one of multiple lineage interchanges between Australia and South America that took place from Late Cretaceous through Early Paleogene via Antarctica. The phylogenetic pattern of lineage accumulation through time of Colletidae indicates an increased rate of cladogenesis beginning in the Eocene, which could be linked to (1) the migration coupled with diversification of two colletid genera which currently are cosmopolitan (Colletes and Hylaeus), or to (2) the climatic and vegetational changes that took place on the southern continents from the Eocene to the Neogene. Biogeography of Austral insects: a comparative molecular phylogenetics approach HARDY N.* (1); COOK L. (2) and TREWICK S. (3) (1) Queensland Primary Industries and Fisheries (2) The University of Queensland, Brisbane (3) Massey University, New Zealand *nbhardy@gmail.com Our understanding of the current distributions of the southern hemisphere biota remains controversial, despite recent studies finding that both vicariance and long-distance dispersal have each played major roles. The interplay between spatial isolation and gene flow is one that can be observed in modern-day species, but there is still a broad perception that much of the austral biota has an “ancient Gondwanan” distribution. Unlike the apparent situation in plants, which show a strong pattern of relatively frequent past long-distance dispersal, the Sanmartin and Ronquist paper of 2004 found that animals better fit a pattern of Gondwanan vicariance. That study relied heavily on insect phylogenies inferred from morphological data and did not account for the timing of events. Here we analyse newly available DNA sequence datasets for about 20 arthropod groups and explicitly consider the timing of inferred divergence events. Our results suggest that arthropod distributions are more similar to that of plants than to the more closely related vertebrates. Biogeography of South American Ephemeroptera MOLINERI C.*; NIETO C.; DOMíNGUEZ E. and DOS SANTOS D. CONICET-Facultad de Ciencias Naturales, Universidad Nacional de Tucumán,Tucumán, Argentina. *cmolineri@csnat.unt.edu.ar The relationships of the South American Ephemeroptera with representatives of other gondwanian continents have been known for a long time. Many families and even some genera are also represented in Australia, New Zealand and Africa. Nevertheless, no formal biogeographic analysis has been presented. In the present study we analyzed the available data using Biogeographic Network Analysis (Dos Santos et al., 2008). We will discuss the patterns detected in South America, and the relationships with the other Southern land masses. Brundin's midges CRANSTON P. (1) and HARDY N.* (2) (1) University of California, Davis, California, USA (2) Queensland PI & F, Indooroopilly, Australia *pscranston@ucdavis.edu Lars Brundin, the Swedish biogeographer, published his ‘Transantarctic relations and their significance: as evidenced by chironomid midges ...’ emphasising austral taxa of the Podonominae, Aphroteniinae and Diamesinae in 1966. His studies of disjunct taxa used morphology of larvae, pupae and adults. Associating immatures and named adults by individual larval rearing, or collections of pharates, is slow. Molecular approaches allow associations via identical sequences in the different stages. Sequences from 4 genes (CO1, 18S, 28S, CAD) test Brundin’s phylogeny. BEAST calibrated by fossils, gives a chronogram to test Gondwanan vicariance dating. Chironomidae subfamilies are monophyletic, originating in the Jurassic. African-Australian sister taxa date to 75 (110-48) mya in Aphroteniinae, and 100 (130-70) my for podonomines Archaeochlus-Austrochlus. Relationships in Podonominae support a monophyletic Podonomini, but Boreochlini is paraphyletic. Major podonomine clades (genera) arose in early-mid Cretaceous. Monotypic taxa for autapomorphic adults (Afrochlus Freeman and Zelandochlus Brundin), lie in speciose genera, as immature morphology suggested. Transantarctic diversification was in the Cretaceous. The conservative Parochlus auraucanus group diversified around K/T boundary (65 mya), and now occupies Andean South America, the subantarctic, New Zealand and Australia, with a Miocene-age expansion into the northern hemisphere. Other boreal taxa are very old, perhaps Pangeaic. Gondwanan and post-Gondwanan elements, but always vicariance: disjunction of old and new circumantarctic elements in the Bibionomorpha (Diptera) AMORIM D.D.S.* Universidade de São Paulo, Brazil *dsamorim@usp.br Tensions about the accepted causes of southern temperate disjunctions are about as old as the evolution theory itself. Dispersalists believe that many groups cannot be understood as Gondwanan, so they accept transoceanic dispersal to explain disjunction. Vicariancists say that there is a general pattern, so vicariance and, hence, Gondwanan origin would be necessary. We use the model of allochrony to discuss the existence of layers of elements of different ages and origins with southern temperate distribution, showing that not all cases of disjunctions are Gondwanan in origin, but there is no need to evoke transoceanic dispersal even for these groups. In the Diptera Bibionomorpha, there is paleontological support to accept that some groups, as the Rangomaramidae, with related fossils in the Jurassic, should be understood as truly Gondwanan. In this group, the Chiletrichinae have recent representatives in southern Africa, but the Ohakuneinae have elements only in South America, New Zealand, and Australia. Some Anisopodidae, with representatives in the Triassic fossil fauna, are also candidates as true Gondwanan, although they are presently not known from New Zealand or Australia. In the Ditomyiidae, there are candidates for recent circumantarctic disjunction, as seems likely also in Mycetophilidae subfamilies Sciophilinae and Leiinae. Odonata from Patagonia: distributional patterns, relationships with other dragonflies and a comparison with other taxa. PESSACQ P.* LIESA, UNPAT *pablopessacq@yahoo.com.ar Objectives The objectives are to present distributional biodiversity, analyses of the relationships of Patagonian dragonflies with those from other areas, and compare with Ephemeroptera and Plecoptera. Methods The information presented is based on existing bibliographies. Results Odonata biodiversity in Patagonia is low, with 36 species in 18 genera and 9 families. This diversity contrasts with the high level of endemicity: 58.3% of the species, 38.9% of the genera and Neopetalidae are unique. Additionally, Petaluridae is transpacific and Austropetalidae is represented also in Australia and New Zealand. Two groups of Odonata can be defined: those from the Subantarctic subregion, representing relictual distributions and with a high degree of endemicity, and those distributed both in the Subantarctic and Patagonian subregions, represented by Neotropical widespread taxa. Ephemeroptera is somewhat similar, with four families being represented in Australia and New Zealand and its entire species endemic to the area, and the remaining taxa in common with the neotropics or with a cosmopolitan distribution. Plecoptera shows a more radical situation, all Patagonian species and Diamphipnoidae are endemic to the region, while the remaining families are represented in Australasia, the southern hemisphere, or are widespread. Conclusions Odonata and other insects of Patagonia reflect the complex history, defined by ancient connection with other areas and the uplift of the Andes. Southern Connected Craneflies: diversity and endemicity; grades and clades (Diptera: Tipulomorpha) RIBEIRO G.C.* Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, Sao Paulo, Brazil *ribeirogc@hotmail.com The Tipulomorpha is one of the largest groups of the Diptera. Knowledge on the phylogenetic relationships among its major lineages and its biogeograhical history is very limited. The Southern Temperate areas of the globe contain a diverse fauna, with a high level of endemic genera, subgenera, and species. Recent studies by the present author has recovered clades of genera and subgenera endemic to South Temperate areas, indicating a biogeographical history associated with the breakup of an ancestral Temperate Gondwanian fauna. In other cases, the distribution patterns favor the hypothesis of a biogeographical evolution associated with the breakup of an ancestral Trans-Pacific biota. The study of the distribution patterns of South Temperate genera, subgenera and species in the Tipulomorpha revealed great diversity of taxa distributed under six major patterns: 1-Southern South America-New Zealand; 2-Southern South America-Australia; 3-Southern South America-Tropical America-Australia; 4-Southern South America-Tropical America-New Zealand-Australia; 5- Southern South America-New Zealand-Australia-Malay Archipelago; 6-Southern South America-Tropical America-New Zealand-Australia-Malay Archipelago. The scale insect fauna of Nothofagus forests: the Australasia-South America links KONDO T.* (1); GULLAN P. (2); HARDY N. (3) and COOK L. (4) (1) CORPOICA, Palmira, Valle, COLOMBIA (2) Dept of Entomology, UC Davis, California, USA (3) Queensland Primary Industries & Fisheries, AUST. (4) The University of Queensland, Brisbane, AUST. *takumasa.kondo@gmail.com The southern beeches, Nothofagus species (Nothofagaceae), have been targeted for biogeographic study due to their Gondwanan distribution. Here we investigate the distribution and host specificity of the scale insect (Coccoidea) fauna associated with Nothofagus. We obtained data from the literature and collection records, and conducted phylogenetic analyses of DNA data from two scale insect groups shared between South America and Australasia. We determined that at least 73 species of scale insects belonging to 26 genera and nine families have been recorded from Nothofagus, with eight of these genera and 56 of the species apparently host-specific to the genus. The largest specialist Nothofagus-feeding genus is Madarococcus Hoy (Eriococcidae), with over 30 named species distributed among Argentina, Chile, Australia and New Zealand. Phylogenetic analysis suggests that the Australian and New Zealand species of Madarococcus form a clade sister to the South American species. Our phylogenetic analyses also suggest that a new species of Callipappidae, collected on Nothofagus in Chile, is related to Callipappus Guérin-Méneville known only from Australia, and Platycoelostoma Morrison with one species in each of Australia, New Zealand and Peru. These intercontinental scale insect distributions could reflect vicariance, ancient dispersal events, or a mix of both, as appears to have occurred for Nothofagus itself. Paleoenvironmental changes since the last glacial maximum: pattern, timing and dynamics throughout the Southern Hemisphere. A chironomid temperature inference model to interpret patterns of climate changes in southern South America MASSAFERRO J.* CONICET *julimassaferro@hotmail.com The degree to which Northern Hemisphere paleoclimate drivers influenced its southern counterpart during the most recent deglaciation (20–10 ka BP) is a hotly debated issue .In southern South America, the debate is primarily focused on the existence of an ACR-like, a YD-like, or a mixture of the two, cooling event at the end of the LGM. The only way to test rigorously the hypothesis of synchroneity (or otherwise), is to generate detailed quantitative palaeoclimatic records from under-represented areas in the Southern Hemisphere to clarify the climatic relationships between the Northern and Southern Hemisphere, and thus identify possible coupling mechanisms. Chironomids (insects) are particularly useful paleoenvironmental indicators, especially for reconstructing changes in temperature. Here I present the results of the first chironomid-based summer temperature reconstructions from southern South America. A training set of 60 taxa from 102 lakes in Patagonia (Argentina and Chile) located along a transect between 40 and 54°S were analysed and summer air temperature was identified as the main driver of chironomid distribution. This model will allow direct comparisons with emerging chironomid-based temperature reconstructions from New Zealand, Greenland and Antarctica ice core records. This study highlights the potential of chironomid-based reconstructions to extend and quantify the late Quaternary paleoclimate history in middle latitudes of South America. Climate reconstruction for southern Patagonia based on the ICDP-Laguna Potrok Aike profiles SCHAEBITZ F. (1); WILLIE M.* (1) and RESEARCH TEAM P. (2) (1) University of Cologne, Germany (2) ICDP - International Cooperation *frank.schaebitz@uni-koeln.de Laguna Potrok Aike located in southern Argentina is one of the very few locations that are suited to reconstruct the paleoenvironmental and climate history of southern Patagonia. In the frame of the multi-national ICDP PASADO project a deep drilling took place where several long cores to more than 100 m depth could be obtained. Here we present first results of pollen analyses from sediment material of the core catcher. Absolute time control is not available so far. Pollen spectra with a spatial resolution of three meters show that Laguna Potrok Aike was always surrounded by Patagonian Steppe. However, the species composition underwent some marked proportional changes through time. The uppermost pollen spectra show a high contribution of Andean forest and charcoal particles as it can be expected for Holocene times and the latest glacial. The middle part shows no forest and relatively high amounts from pollen from steppe plants indicating cold and dry high glacial conditions. The lowermost parts of both cores show a significantly different species composition as steppe plants like Asteraceae, Caryophyllaceae, Ericaceae and Ephedra became more frequent. In combination with a charcoal contribution and an algal species composition comparable to Holocene characteristics we suggest that conditions at that time were more humid or warmer causing a higher fuel production compared to full glacial times. Holocene shallow lakes evolution from south-eastern Pampa grasslands, Argentina STUTZ S.* (1); BOREL C.M. (2); DEL PUERTO L. (3); INDA H. (3) and GARCIA-RODRIGUEZ F. (3) (1) Paleoecología y Palimología FCEyN UNdMP-CONICET (2) Palinología INGEOSUR-Depto Geología, UNS CONICET (3) Facultad de Ciencias Universidad de la República U *silstutz@yahoo.com.ar In south-eastern Pampa grasslands there is a large number of similar lakes developed in Pleistocene deflation basins. They are plain lakes, very shallow, polimyctic, eutrophic or hypertrophic which exhibit water renewal and fluctuating salinity. They have similar plant communities characterized by a defined ring of emergent plants (Schoenoplectus californicus), submerged plants (Myriophyllum, Ceratophyllum ) and a carpet of floating-leaved plants. Pollen, NPPs, diatoms, phytoliths, ostracods, macro plants remains, organic matter and carbonate content, were used as proxies to evaluate lakes evolution and then integrate them in a regional environmental and climate history. In this work, we present results from Tobares, Loncoy, Nahuel Rucá and Hinojales lakes. The early Holocene is only represented in Lake Tobares where pollen and NPPs suggest a very shallow system without modern analogous. Around 5500 14C yr BP, Hinojales and Nahuel Rucá were affected by high standing sea level reflecting marine influence, indicated by almost all the proxies. After this, both lakes evolved similarly, showing shifts from clear to turbid states. During the late Holocene all lakes showed similar spectra indicating that modern lakes began to establish during this time, even though anthropogenic activity greatly modified them in the last two centuries. How fire and climate shaped grass dominated vegetation in South Africa in past millennia BREMAN E.* (1); GILLSON L. (2) and WILLIS K. (1) (1) Oxford University Centre for the Environment (2) University of Cape Town, Botany Department *elinor.breman@ouce.ox.ac.uk Key questions for understanding the resilience and variability of grass-dominated ecosystems in southern Africa under current and future climate change include: How have these systems responded to disturbance in the past? What are the principal driving agents responsible for their present-day composition and distribution? Are current theories on the effects of fire and climate control of vegetation in accordance with the long-term data from these systems? In this study the temporal dynamics of grassland and savanna in South Africa during the last ~6000 years were reconstructed using palaeoecological techniques. These include analyses of fossil pollen, charcoal, phytoliths and stable isotopes. Data from sites located at the present-day ecotone in the summer rainfall region are reported. Results indicate that a mosaic of grassland, savanna and northern escarpment mist-belt forest occupied the landscape throughout the late Holocene, grassland and forest dominating higher altitudes, savanna and forest lower altitudes. During this time, however, there have been changes in the vegetation, notably the extent of woody cover which has declined since 1,500 BP. Fire is shown to have closer links to changes in vegetation cover than climate (cool, dry events), but the relationship does not explain all of the variation at the landscape scale. Human use of the region has been of increasing importance in shaping vegetation in the last millennia. Insights gained from Holocene fire history studies in Patagonia, New Zealand, and northwestern U.S. WHITLOCK C.* (1); IGLESIAS V. (1); MCWETHY D. (1); BIANCHI M.M. (2) and WILMHURST J. (3) (1) Montana State University (2) INIBIOMA CONICET (3) Landcare Research *whitlock@montana.edu Information on past fire activity comes from charcoal data spanning millennia, tree-ring records of the last few centuries, and historical reports. Studies from Patagonia, New Zealand, and the northwestern US illustrate our understanding of the linkages between fire, climate, vegetation, and human activity on multiple temporal and spatial scales. For example, charcoal records from Patagonia and the northwestern US show widespread fire activity in the early Holocene as a result of strengthened subtropical high-pressure systems and weakened westerlies; this period has relevance for projections of fire conditions in the future. Reconstructions from Patagonia document the sequence of changes in climate and fire occurrence that allowed expansion of Austrocedrus in the mid-Holocene and led to subtle shifts in the forest-steppe ecotone in the late Holocene. In New Zealand, paleoecologic data reveal the consequences of deliberate burning following the arrival of people and the cascading ecosystem effects of introducing a new disturbance. In Patagonia and the northwestern US, it is difficult to discern the effects of human-set from naturally-ignited fires in prehistoric times, in contrast to the distinct alteration of fire regimes by Europeans. Paleofire studies thus provide essential information for the future, including (1) the consequences of climate change on fire activity, (2) fire’s role in vegetation reorganization, and (3) human impacts on natural fire regimes. Late Quaternary vegetation, biodiversity and fire dynamics in southern Brazil BEHLING H.* University of Göttingen, Department of Palynology *Hermann.Behling@bio.uni-goettingen.de Palaeoecological background information is needed for management and conservation of the highly diverse mosaic of Araucaria forest and Campos (grassland) in southern Brazil. Questions on the origin of Araucaria forest and grasslands, its development, its biodiversity, dynamic and stability, its response to environmental change such as climate, and the role of human impact, are essential. Further questions on its natural stage of vegetation or its alteration by pre- and post-Columbian anthropogenic activity are also important. To answer these questions, palaeoecological and palaeoenvironmental data based on pollen, charcoal, and multivariate data analysis of radiocarbon dated sedimentary archives from southern Brazil are used to provide an insight into past vegetation changes that allow us to improve our understanding of the modern vegetation and to develop conservation and management strategies for the strongly affected ecosystems in southern Brazil. Long term vegetation dynamics in Northern Argentinian Lake District GIESECKE T.* and FONTANA S. University of Göttingen, Germany *thomas.giesecke@biologie.uni-goettingen.de Vegetation types in Patagonia are mainly determined by the amount of precipitation, ranging from rain forests in the west to steppe grasslands in the east. Latitudinal and altitudinal gradients, determined by temperature, can also be observed. Over most of the Holocene the vegetation was influenced by fire and volcanic eruptions, but relative undisturbed by humans. To study long term dynamics of the forest steppe ecotone, we sampled two lakes 10km apart: within a dense Nothofagus forest and in open Araucaria araucana woodland. Here we present the results of lake Torta (39°06’S, 71°21’W; 1090m asl) located in a mixed forest of N. obliqua and N. antarctica with A. araucana. The 10m sediment core recovered is intercalated with numerous tephra layers of varying thickness (up to 70cm tick). Other distinct layers can be recognised by high magnetic susceptibility, low pollen concentration and presence of fungal fruit bodies. These layers, interpreted as flood events, reveal insight into the abundance of plants with low pollen production or dispersal that occur on the valley floor. After deglaciation, the vegetation around the site was open woodland with Nothofagus species, Austrocedrus chilensis and steppe elements. The occurrence of A. araucana pollen indicates that also this species was already present in the region. The forest composition shows stability with gradual change in species abundance, indicating that volcanic eruptions have no significantly affected the vegetation. Long term vegetation history in the Río Manso catchment area, Northern Patagonia. Pollen as proxy record BIANCHI M.M. (1); WHITLOCK C. (2); IGLESIAS V.* (2) and PÉREZ C.F. (3) (1) INIBIOMA CONICET (2) Montana State University (3) Departamento de Ciencia de la Atmósfera y los Océa *mariam@bariloche.com.ar The Manso River originates in the El Manso Glacier of Cerro Tronador and discharges into the Pacific Ocean after flowing along 81 km on a mountain landscape. It is divided in: The Manso Superior, Medio and Inferior rivers. Pollen studies in this watershed allowed us to gain a better understanding of the vegetation history at different time scales. Pollen transport over the Andes by trajectory analysis of air masses has been shown to occur in the watershed and pollen rain studies are in progress. Preliminary results from a 7- m-long sediment core from Lake Huala Hué (41° 30’S -71° 30’ W), Manso Medio river basin, show that Nothofagus dominates most of the sequence with highest values of Cupressaceae, probably Austrocedrus chlensis, after its expansion, ca. 5700 cal yrs B.P. The area exhibited high fire frequency during the last centuries. Research in the Río Manso Superior watershed, included a pollen record from Lake Mascardi (41°08’S, 71° 34’ W), extending back to the Late Glacial period. Forest diversification took place with amelioration of climatic conditions and the vegetation became more open during the Huelmo-Mascardi cold reversal. Ancient Nothofagus forest was replaced by mixed Nothofagus- middle Holocene, forest, and became denser under higher climate variability during the late Holocene. Statistical analyses of modern pollen from surface samples along an altitudinal transect from high- Andean to low Nothofagus forest support this interpretation. Palaeoenvironmental changes since the Last Glacial Maximum in Southern New Zealand VANDERGOES M.* (1); NEWNHAM R. (2); DIEFFENBACHER-KRALL A. (3); DENTON G. (3) and WILMSHURST J. (4) (1) GNS Science (2) University of Plymouth (3) University of Maine (4) Landcare Research *m.vandergoes@gns.cri.nz Detailed, quantitative records of past climate change are essential for understanding the temporal pattern and magnitude of change in the Southern Hemisphere since the Last Glacial Maximum (LGM). Here we present a summary of climate change emerging from terrestrial palaeoecological proxies in southern New Zealand. We use continuous, isotopically dated, paleo-chironomid and pollen records to construct quantitative estimates of climate change from 30,000 to 10,000 cal BP. Preliminary pollen and chironomid inferred temperature reconstructions for the LGM compare well with both indicating an approximate 5.5-7.0 oC temperature depression during the coldest parts of the LGM and cooling of between 3.5-4.5 oC during the LGM interstadials. Since the LGM, pollen and chironomid records indicate a ca. 1000-year disruption to the Lateglacial warming trend and an overall cooling consistent with the Antarctic Cold Reversal. The main interval of chironomid-inferred temperature depression (~2–3 oC) lasted about 700 years and was followed by a warming step to temperatures slightly cooler than present during the Younger Dryas chronozone (12,900–11,500 cal BP). The results highlight a direct linkage between Antarctica and mid-latitude terrestrial climate systems and provide opportunities for comparison with other Southern Hemisphere records to help clarify climate relationships and distinguish climate coupling mechanisms. Paleoclimate proxy records from southern South America and the Westerly stormtracks MARKGRAF V.* (1); GILLIL A. (2); SCHWALB A. (3) and ARIZTEGUI D. (4) (1) University of Colorado/INSTAAR, USA (2) ETH, Zurich, Switzerland (3) University of Braunschweig, Germany (4) University of Geneva, Switzerland *vera.markgraf@colorado.edu Inferences on the behavior of the Southern Westerly’s stormtracks in southern South America during the late Quaternary were made on the basis of precipitation-sensitive proxies such as revealed in records of past changes in vegetation, fire frequency and lake levels. Seismic data and multi-proxy evidence from the deep-water core from Lago Cardiel (49°S, 76 m water depth, 379 km2 area, ~ 10km east of the Andean cordillera) document a history of marked lake level fluctuations that can be related to past environmental changes and interpreted in terms of latitudinally shifting westerly stormtracks. Postglacial vegetation dynamics of western Tierra del Fuego FONTANA S.* (1) and BENNETT K. (2) (1) University of Göttingen, Germany (2) Queen's University, Belfast, UK *k.d.bennett@qub.ac.uk Vegetation changes observed in palaeoecological records are usually attributed to climatic change, volcanic eruptions, fire and human activities. Internal processes such as dispersal, competition and succession have also lead to changes in vegetation and it has proven difficult to separate the former from the latter. Southern South America is a critical region for assessing the relative role of different drivers for vegetation change, because (i) there is a range of vegetation types along climate gradients, (ii) has been influence by volcanic eruptions, fire, but relative undisturbed by humans, and (iii) is close to independent climate records from Antarctica. We present a record of changes in vegetation over the past 16000 years, from a lake in the Magallanes region (53° 38.97S; 72° 25.24W). After deglaciation, Lycopodium and Gunnera dominated the vegetation for more than 4500 years. Nothofagus established in the region over a period between 12000-9500 cal. BP, but populations must have been small. After 9500 cal. BP populations around the site expanded rapidly. Nothofagus became most abundant after the Mt Burney MB2 eruption and slowly declined thereafter to its present abundance. This pollen diagram shows no indication of a major cold reversal during the late Glacial but rather indicates gradual climate amelioration as traced by changes in species abundance and leading to immigration of new taxa with competitive interactions between the new and the residentiary species. Quantitative palaeoclimatic reconstructions in southern South America: progress and difficulties TONELLO M.S.* Universidad Nacional de Mar del Plata *mtonello@mdp.edu.ar The first paleoclimatic reconstructions in southern South America presented some methodological difficulties such as the scarcity of the pollen and climate data used into calibration set and the presence of fossil pollen assemblages without close modern analogues. Some progresses have been done recently to achieve more accurate calibration sets which lead to good performances to estimate annual precipitation. Thus, the compiled modern pollen data consisted of samples from similar sedimentary environments (surface soil samples), collected from undisturbed or minimally disturbed sites, and with a wide and uniform spatial coverage. Difficulties arose regarding the modern climate data since the instrumental meteorological record is fragmentary and does not completely span the Climate Normal period. Climate data were taken from different global climate data bases giving an accurate reflection of the climate gradient in most of the areas although presenting some bias in others. Different methodologies were applied on fossil pollen records located in the climatologically and ecologically sensitive grasslands-xerophytic woodland and forest-steppe ecotones, and annual precipitation trends were reconstructed for the last ca. 12000 cal yrs in the Pampa region and southern Patagonia. The paleoclimatic reconstructions were consistent with previous interpretations suggesting that the reconstructed features reflect changes in large-scale atmospheric circulation patterns. Insights on Southern Hemisphere plant species richness, endemism and colonization. Believing six impossible things before breakfast JORDAN G.* University of Tasmania *greg.jordan@utas.edu.au When the Queen in Alice in Wonderland said “Sometimes I've believed as many as six impossible things before breakfast” she touched the core of science. Progress in science often comes from seemingly irreconcilable contradictions - ignoring such contradictions is common, but poor science. This talk is about contradictions implicit in the biogeography of cool temperate rainforest plants with low vagility. Molecular date and/or fossil evidence suggest high rates of intercontinental long distance dispersal. However, phylogeography implies extremely low rates of migration by seed. Also distributions within continents are generally discontinuous (and are unlikely to have been continuous in any sense relevant to this argument). Thus, vicariance events resulting from continental breakup are inevitably compounded by vicariance within continents. As such, the minimum ages for intercontinental vicariant disjunctions should consider the potentially large amounts of time for intracontinental dispersal to the ages of continental breakup. This increases the anomalies between ages inferred from fossil/molecular dating approaches and inferred times of vicariance. One resolution is frustrating to those seeking mechanistic explanations of distributions - that broad scale distributions are established by largely unpredictable, stochastic events that bear little relationship to known dispersal traits. Empirical, probabilistic modelling of extreme long distance dispersal may provide answers. Diversification of the Proteaceae in Mediterranean hotspots of the Southern Hemisphere and in tropical rainforests WESTON P.* (1); SAUQUET H. (2); MAST A. (3) and BARKER N. (4) (1) National Herbarium of New South Wales, Australia (2) Université Paris-Sud, Orsay, France (3) Florida State University, Tallahassee, USA (4) Rhodes University, Grahamstown, South Africa *peter.weston@rbgsyd.nsw.gov.au Objectives Southwest Australia and the Cape Floristic Region are 2 biodiversity hotspots with Mediterranean climates that share key features such as high levels of endemism, nutrient-poor soils, and frequent fire regimes. We aimed to test whether high species richness in the Proteaceae is the result of recent radiation (due to high speciation rates) or long accumulation of lineages over time and to explore potential explanations for such patterns. Methods The phylogeny of the Proteaceae was reconstructed down to generic level using alignments of eight nuclear and chloroplast loci. Clade ages were estimated using three different relaxed clock dating methods and seven age constraints obtained from a phylogenetic analysis of the family’s rich fossil pollen record. Global rates of speciation and extinction for Proteaceae were calculated and used to test whether speciation rates are significantly higher in Mediterranean hotspot clades than in other clades. Results The net diversification rate for Proteaceae is comparable to that of angiosperms as a whole. The highest diversification rates are found in Mediterranean hotspot lineages, with the exception of the predominantly Southeast Asian tropical rainforest genus Helicia. However, not all hotspot lineages appear to have experienced unusually high diversification rates. Conclusions Diversification in the SWA and CFR hotspots appears to have increased gradually over an extended period, from 40 mya. Elements of the Patagonian flora with origins in western North America: dispersal, speciation, and extirpation. JOHNSON L.* Brigham Young University *leigh_johnson@byu.edu Amphitropical disjunct distributions between western North American and western South America have intrigued botanists for over a century. Here, specific examples of migration and speciation are investigated using herbaceous species, primarily from the phlox family (Polemoniaceae), as a model for considering the timing of dispersal relative to speciation events such as allopolyploidization. For example, approximately 34 of 35 species of Navarretia and 14 of 15 species of Collomia are native to western North America. The earliest named entities in both genera, however, are single species native to South America that occur in comparable habitats to their North American counterparts along either side of the Andes. Several other genera of Polemoniaceae, for instance Ipomopsis, Leptosiphon, and Gilia, show similar biogeographic patterns that support a North American origin of the temperate genera of Polemoniaceae as well as multiple dispersal events to South America usually associated with the formation of novel species. In Navarretia and Collomia, the South American species are allopolyploids, suggesting either two dispersals prior to the allopolyploidization event for each species with subsequent extirpation of the diploid progenitors from South America, or allopolyploid formation prior to dispersal with extirpation of these polyploids from North America. Character evolution and taxonomy of these exemplar species are elaborated in light of both morphological and molecular data. Evolutionary origin of the Asteraceae capitulum: insights from Calyceraceae POZNER R.* (1); ZANOTTI C. (1) and JOHNSON L. (2) (1) Instituto de Botánica Darwinion, CONICET - ANCEFN (2) Brigham Young University, Biology Dept. *rpozner@darwin.edu.ar The Menyanthaceae+Goodeniaceae+Calyceraceae+Asteraceae clade is well supported by molecular and morphological data, with Calyceraceae the sister group of Asteraceae. The two basal families share a basic monotelic thyrse-panicle inflorescence structure, which is not evidently connected with the typical capitulum of Asteraceae that is widely interpreted as a polytelic, condensed inflorescence. The structure of Calyceraceae inflorescences is poorly understood, yet such understanding may show how the Asteraceae capitulum evolved from monotelic inflorescences. We used SEM to study the development and structure of the inflorescence of 8 species of Calyceraceae and found their basic inflorescence structure is a cephaloid. This structure is like a pauperized panicle with undeveloped internodes, and connects the panicle-thyrse inflorescence of Menyanthaceae and Goodeniaceae with the capitulum of the Asteraceae through 2 morphological changes: reduction of the first order branches, and loss of the terminal flower. We optimized inflorescence characters on a set of trees derived from ITS sequences that were rooted with Dampiera (Goodeniaceae) and included two Asteraceae taxa. Results suggested that simple cephalodia (Boopis, Acicarpha) and true capitula of Asteracae could have appeared as early as the ancestor of the Goodenianceae (Calyceraceae+Asteraceae) clade, while complex cephalodia observed in the remaining Calyceraceae genera are reversions towards richer, condensed panicles. Geochronology of Southern plant clade appearances: Examples from Patagonia WILF P. (1); CúNEO N.R. (2); GANDOLFO M.A. (3); IGLESIAS A. (4) and JOHNSON K.R.* (5) (1) Pennsylvania State University, USA (2) Museo Paleontológico Egidio Feruglio, Argentina (3) Cornell University, USA (4) Universidad Nacional de La Plata, Argentina (5) Denver Museum of Nature & Science, USA *pwilf@psu.edu Molecular data do not yield accurate clade ages, for which well-identified fossils from well-dated rocks comprise the only reliable information. We report on extremely diverse and heavily sampled latest Cretaceous through middle Eocene floras from Chubut and Río Negro provinces in Patagonia, Argentina, the biogeographic crossroads of South America and Australasia via Antarctica. The Campanian-Maastrichtian La Colonia Formation and lower Lefipán Formation, the terminal Maastrichtian upper Lefipán Fm., and the ca. 61.7 Ma Salamanca and Peñas Coloradas fms. represent coastal lowland environments. The age estimates for these sites are derived from microfossil biostratigraphy and magnetic stratigraphy. At the Eocene sites, which represent caldera lakes, volcanic ash beds in the lake sediments yield precise 40Ar-39Ar ages of 54.24 ± 0.45 Ma for the Pampa de Jones flora, 51.91 +/- 0.22 Ma for the Laguna del Hunco (LH) flora, and 47.46 +/- 0.05 Ma for the Río Pichileufú flora. At LH, the global correlation is further improved from six magnetic polarity reversals present in the lake sequence. These results contribute a considerably improved geologic framework to the South American component of plant evolution in Gondwana. Examples of well-dated discoveries are Cretaceous Nelumbonaceae fruits and leaves, Paleocene Brassicales flowers and leaves, Eucalyptus and Gymnostoma at LH, and diverse conifers throughout including Eocene Papuacedrus, Acmopyle, Dacrycarpus, and Retrophyllum. Origins and diversification of the Australian monsoon tropics flora CRISP M. (1) and COOK L.* (2) (1) The Australian National University (2) The University of Queensland *mike.crisp@anu.edu.au Most of northern Australia experiences a monsoonal climate of extreme wet and dry seasons. It has outstanding wilderness value with three World Heritage areas and diverse communities including savannah, sclerophyll and dry-season deciduous rainforest. Studies on the evolutionary origins of this unique flora have lagged behind those on southern biomes. This review contrasts two competing theories: that the Australian monsoon tropical flora is unique, having evolved in situ by fragmentation and ecological sifting of an ancient Gondwanan flora; or that it consists of elements that have immigrated recently from Asia and Africa. Our approach focuses on comparisons across multiple dated molecular phylogenies of plant groups with diverse life histories and phylogenetic relationships, including Brachychiton (kurrajongs, bottle trees), Casuarina (she-oaks), Cycas (cycads), eucalypts (Eucalyptus and Corymbia), Jacksonia and Daviesia (Fabaceae), Livistona (fan palms), Melaleuca (paperbarks) and Triodia (spinifex). We address following questions: 1. What are the geographic origins of the monsoonal flora? 2. Was the flora assembled piecemeal over a long period or did it arise in a narrow time window, implying a driver such as origination of the monsoon (as early as the Eocene?), or climate change in the Miocene? 3. What are the biogeographic links between the three distinct monsoonal regions (Kimberley, Top End and Cape York Peninsula) and were they isolated at different times?. Phylogenetic component of patagonian seed plant diversity NIXON K.; HERMSEN E.* and GANDOLFO M. Cornell University *ejh23@cornell.edu The Patagonian region encompasses a relatively mild temperate climate regime with a wide range of rainfall and topographic variation. This climatic and topographic diversity contributes to distinct vegetation types including arid scrub, coniferous woodlands, Nothofagus-dominated temperate deciduous and evergreen forests, and the enriched Valdivian forests. Phylogenetic connections in the Andean flora occur with other South Temperate areas, most notably the Nothofagus-dominated forests of New Zealand, Australia and Tertiary forests of Antarctica. In contrast, the arid areas show at least superficial affinities with North American deserts (e.g., Larrea, Prosopis, various Asteraceae), but also exhibit high species diversity in some unexpected groups, such as Verbenaceae. In this study we will compare the phylogenetic affinities of the various vegetation types of Patagonia with similar climatic regions both in the Northern Hemisphere and Southern Hemisphere, including the Southwestern US, Mediterranean, Australia and South Africa for temperate/subtropical dry regions. Simultaneous comparisons will also be made with the dry subtropical/tropical regions of northern Argentina, which is a likely source for the distinct xerophytic vegetation of the Patagonian steppes. Because of issues related to comparability of taxa at the same and different ranks, a new method and software that reduces taxonomic redundancy and mismatch by counting nested clade representation will be presented. Testing the impact of calibration on molecular divergence times using a fossil-rich group: the case of Nothofagus SAUQUET H.* (1); SIMON Y. W. H. (2); GANDOLFO M.A. (3); JORDAN G. (4); WILF P. (5); CANTRILL D.J. (6); BAYLY M. (7); BROMHAM L. (2); BROWN G. (6); CARPENTER R.J. (8); LEE D.M. (5); MURPHY D. (6); SNIDERMAN J.M.K. (9) and UDOVICIC F. (6) (1) Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France (2) Centre for Macroevolution and Macroecology, Research School of Biology, Australian National University, Canberra ACT 0200, Australia (3) L.H. Bailey Hortorium, Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA (4) School of Plant Science, University of Tasmania, Private bag 55, Hobart, Tas., 7001, Australia (5) Department of Geosciences, Pennsylvania State University, University Park, PA 16802, USA (6) National Herbarium of Victoria, Royal Botanic Gardens Melbourne, Private Bag 2000, South Yarra, Victoria 3141, Australia (7) School of Botany, University of Melbourne, Victoria 3010, Australia (8) Department of Ecology and Environmental Biology, School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Australia (9) School of Geography and Environmental Science, Monash University, 3800 Victoria, Australia *herve.sauquet@gmail.com Objectives Calibration is now widely recognized as a critical step in obtaining accurate divergence time estimates from molecular dating methods, but few studies have addressed the variance resulting from different calibration strategies. This study tests the impact of various calibration scenarios on molecular dating inference. Methods We conducted an empirical study of 8 plausible calibration scenarios for Nothofagus (Fagales), a plant group with a particularly rich and well-studied fossil record. Molecular dating analyses were conducted for each scenario using six loci and maximum likelihood (RAxML + PL) and Bayesian (BEAST) approaches. Results Using either ingroup or outgroup constraints, or both, leads to similar ages, except near strongly influential calibration nodes. Using “early but risky” fossil constraints (e.g., pollen) in addition to “safe but late” constraints (e.g., macrofossils), or using assumptions of vicariance instead of fossil constraints, leads to older ages. Using a secondary calibration point leads to drastically younger ages. Conclusions This study highlights the critical influence of calibration on molecular dating analyses. Even in a best-case scenario, with many fossils available, large uncertainties remain. Increased background research should be made at all stages of the calibration process, from obtaining the latest geochronological data on the fossils to the critical re-assessment of their phylogenetic position. Physiological adaptations in the Southern Hemisphere: are there convergences among Gondwanian land masses in cold-blooded vertebrates? Evolution of live-birth in southern hemisphere lizards THOMPSON M.* (1) and MURPHY C.R. (2) (1) School of Biological Sciences University of Sydney (2) University of Sydney School of Medical Sciences *Mike.Thompson@bio.usyd.edu.au Viviparity (or live-birth) has evolved frequently (more than 100 times) in Squamate reptiles, but complex placentae have evolved rarely (five times). Three of the five occurrences of complex placentae occur in the Eugongylus group of skinks from Australia and New Zealand. We have used the range of Australian viviparous skinks to ask: 1. What steps are involved in the evolution of viviparity? 2. What are the commonalities and differences between species in which complex placentae have evolved independently? 3. What are the functions of different regions of the placenta and in particular the uterine epithelial cells? The evolution of viviparity involves retention of eggs and a reduction in the eggshell. Complex placentation is correlated with a reduction in egg size, an increase in uterine vasculature and regional specialization of placentae for gas or nutrient exchange. Comparison of nutrient exchange and placental structure reveals that structural complexity and nutrient transport are only loosely correlated. The Eugongylus groups provides an excellent model for studies of the evolution of viviparity because it shows a range of reproductive modes and three independent origins of complex placentae. To date, we have generated hypotheses about the evolution of complex placentae using species from two of the lineages of Eugongylus group skinks (from south-eastern Australia), which we are now testing in the third (New Zealand) lineage. Evolutionary convergence and divergence in the colonization of extreme habitats by South American anurans NAVAS C.A.* Universidade de São Paulo *navas@usp.br Anuran amphibians occupy contrasting ecological settings in South America, ranging from semi-arid environments such as the Brazilian Caatingas to tropical high-elevations of the Andes at more than 4000m. Such contrasting habitats differ enormously in terms of thermal regime, water availability and other physical traits of the environment that are ecologically relevant to anurans. Despite the apparent ecological challenge to frogs, these two environments have been colonized by anurans in a series of independent evolutionary events, each representing taxa with expressive divergence in natural history. Is this presentation I discuss some of the mechanisms allowing for the colonization of these two extreme environments by a diverse array of anuran taxa. Then, I discuss more generally the relative role of physiological specialization, behavioral flexibility and ecological associations in the colonization of extreme environments by anurans, pointing out to some interesting contrasts in evolutionary pathways. Hormones and reproduction in viviparous reptiles from Tasmania: adaptations to a cool southern climate JONES P.S.M.* University of Tasmania *S.M.Jones@utas.edu.au The reptiles of Tasmania, the southern island state of Australia, exhibit a suite of adaptations to cool/cold climates. Fifteen of the seventeen species of skink are viviparous, with a range of reproductive strategies. Some species undergo gonadal development and mating in spring. Others exhibit asynchronous gonadal cycles: testicular development peaks in late summer, but females begin vitellogenesis in autumn and complete it after hibernation; mating occurs in autumn and spring with both sexes storing sperm. The three specialist alpine species exhibit biennial reproductive cycles. After ovulation in spring, females carry fully developed embryos through hibernation and well into the next spring. Annually breeding species may also retain fully developed embryos in utero: in adverse conditions, the metallic skink can delay parturition for up to four weeks. These observations raise questions about the proximate stimuli that regulate the hormones controlling parturition: do both environmental and embryonic cues contribute? We used radioimmunoassay to measure plasma hormones and tissue incubations to assess the capacity of maternal and embryonic tissues to produce hormones in vitro. Results indicate that, in the alpine species Niveoscincus microlepidotus and the lowland species N. ocellatus, placentae are steroidogenic, and embryonic adrenals produce corticosterone. This suggests a potential role for the embryonic adrenals in signalling to the maternal endocrine system. Reproduction in cold climates: do female geckos from New Zealand differ from their southern-hemisphere counterparts? CREE A. and HARE K.M.* Department of Zoology, University of Otago *alison.cree@stonebow.otago.ac.nz New Zealand poses similar climatic challenges for lizards to other southern, high-latitude landmasses. Extended life histories are common and often attributed to the effects of cool temperature. However, experimental evidence for thermal effects on specific phases of reproduction is limited, especially for nocturnal species. We compared the effects of three thermal regimes on pregnancy in the viviparous common gecko (Hoplodactylus maculatus). In the wild, embryonic development extends from spring until late summer, with birth delayed until the following spring, producing a biennial cycle. We hypothesised that a warmer thermal regime would allow shorter gestation, with higher incidences of spontaneous parturition and resumption of vitellogenesis prior to parturition than under cooler regimes. Mean gestation length was indeed inversely related to heat availability, but still remarkably long (178 days under the warmest regime for those delivering spontaneously). The resumption of vitellogenesis during pregnancy was most frequent under the warmest regime (91% of females). This phenomenon appears unique to New Zealand geckos, allowing a new reproductive cycle to begin without immediate delivery of young. Spontaneous parturition was infrequent (45% of females) and may require additional, non-thermal factors. Years of skipped reproduction appear rare in New Zealand lizards, perhaps because winters are less severe than in some South American locations. Reproductive biology and thermoregulation of a viviparous lizard Sceloporus serrifer in a warm environment: consequences on the global climate change MéNDEZ DE LA CRUZ F.R.* Universidad Nacional Autónoma de México, C.P. 045 10, A.P. 70-153 México D.F. México *faustor@ibunam2.ibiologia.unam.mx Global warming has been considered to promote extinctions in several groups of living forms. Recent surveys in México show dramatic variations in lizards, affecting distributions or even promoting local extinctions. In order to understand the factors that are affecting lizards we studied a species that occurs in an extreme warm environment to viviparous Sceloporus. The viviparous forms of Sceloporus occur in mountain environments and only a few species are present at low elevations. S. serrifer is a viviparous lizard that occurs close to sea level (20 m) in a warm environment. Its reproductive cycle is typical from viviparous species in México: fall mating and winter ovulation and gestation whereas birth occurs during early spring. Selected temperatures, as the ones from the Torquatus group, are around 32 ºC whereas operative temperatures are between 20 to 58 ºC. Pregnant females should not be exposed to temperatures higher than 35 ºC as are deleterious to embryos. During gestation period occur the highest environmental temperatures in the area; therefore thermoregulation of lizards is restricted to early hours (from 6:00 to 10:00 AM). A minimum of 4 hours active at day will be critical to survive. Global warming affects already some southern populations and operative temperatures restricts the period of activity of lizards to less than 4 hours, promoting local declination. The Gondwanian heritage of Patagonian fishes: physiology and life history CUSSAC V.E.* INIBIOMA *vcussac@crub.uncoma.edu.ar South America has a distinctive trait amongst land masses of the Southern Hemisphere; its vast latitudinal range (from 12ºN to 56ºS). Since the opening of the Drake Passage during the Tertiary and the subsequent climate cooling, the original freshwater Gondwanian fish fauna underwent a gradient of selection pressures applied on thermal tolerance and capacity to endure winter starvation. Later, marine incursions and glaciations added major traits to this scenario and this ensemble of selection pressures acting on physiological and life history capabilities drove to the persistence of some groups of siluroids (Diplomystiidae, Trichomycteridae) and characins (Cheirodon, Gymnocharacinus) or to the replacement by a successful marine related fish fauna (Percichthyidae, Atherinopsidae, Galaxiidae). The adaptations displayed included tolerance to low temperature, low oxygen availability, darkness and abrasion, use of thermal habitats, bigger eggs, use of warmer breeding habitats, different breeding seasons, and migration within freshwater or between freshwater and the sea. Thus, present landscape shows the paradoxical situation of a severely impoverished fish fauna (only four native species in Tierra del Fuego Island) and a rich menu of ecological relationships, amongst species and between species and environment, mediated by eco-physiological and eco-morphological adaptations and life history adjustments. Thermophysiology in liolaemids from Patagonia: Has evolution written comparative stories in Gondwanian lands? IBARGüENGOYTíA N.* (1); MEDINA M. (2); FERNáNDEZ J. (3) and SCOLARO A. (4) (1) Centro Regional Universitario Bariloche UNC INIBIOMA (2) Centro Regional Universitario Bariloche UNC INIBIO (3) Centro Regional Universitario Bariloche UNC (4) U Nac. de la Patagonia San Juan Bosco CENPAT *norai@bariloche.com.ar Natural selection should favor a co-evolution of traits strongly related to fitness, and for ectotherms, of prime importance should be behaviors that influence the effectiveness of thermoregulation (E) and hence, the body temperature (Tb). In cold temperate climates, reptile life histories have adapted to prolonged periods of resource scarcity, producing a variety of similar evolutionary paths resulting in convergence among different lineages. We compare the Tb’s and operative temperatures in the field, preferred Tb’s from the laboratory (Tp), and E values of liolaemids from Patagonia, Argentina, to that of reptiles from similar latitudes elsewhere in the Southern Hemisphere. At high latitudes, the liolaemids show significant limitations in thermoregulation; they are poor thermoregulators or “constrained thermoconformers” and they show the lowest Tb’s for the genus (23-26ºC). The Tp’s, a very conservative character in liolaemids, are significantly higher (32-34ºC) than the environmental temperatures in Patagonia; they are not likely to be achieved in nature. The large differences between Tb and Tp in some species suggest that their ancestors lived at lower latitudes and their descendents now face extreme physical challenges and have had insufficient time to evolve appropriate thermoregulatory behaviors or to make adequate physiological adaptations. Controversies in the Quaternary of the Southern Hemisphere A 150,000 -Year Record of Temperature and Rainfall from Lake Malawi, East Africa JOHNSON T.* (1); BERKE M. (1); WOLTERING M. (1); WERRNE J. (1) and SCHOUTEN S. (2) (1) University of Minnesota Duluth (2) Netherlands Institute of Sea Research *tcj@d.umn.edu A paleotemperature record from Lake Malawi (10º - 14º S) spans the past 150,000 years, based on analyses for TEX86 in drill core sites in the central and north basins of the lake. This is the longest continuous record of temperature thus far recovered from the African continent. The temperature records for the past 25,000 years are quite consistent between the two sites, with post-glacial warming beginning around 20 ka, and maximum temperatures centered on about 10-14 ka, 4-6 ka, and the present. The north basin temperature record extends back to 75 ka, and shows little evidence for millennial scale variability during MIS 3, despite XRF scans of the core that clearly indicate Dansgaard-Oeschger – type oscillations in the wind field. Maximum cooling at this site occurred at the end of MIS 4, when the lake cooled 6ºC in 10 ky, arriving at a temperature that was about 2ºC cooler than the LGM. Drilling at the central basin site recovered 380 m of core, of which the upper 90 m have thus far been analyzed for TEX86. Prior to 75 ka, the temperature profile exhibits greater variability, with measurable response to higher amplitude precessional forcing than has occurred since that time. Thus the megadroughts in East Africa that occurred prior to 75 ka appear to have been accompanied by temperature shifts of 4 – 5º C, somewhat greater than the 3.5º C shift that occurred between the LGM and today. A re-assessment of patterns and causes of change during the Last Glacial Cycle in Australia based on palynological evidence KERSHAW A.P.* (1); ROBERTS R.G. (2); TURNEY C.S.M. (3); BROWN J.H. (1) and MCKENZIE G.M. (1) (1) Monash University (2) University of Wollongong (3) University of Exeter *peter.kershaw@arts.monash.edu.au Pollen records have been important in providing a chronology of environmental change in the Australian region prior to the traditional limit of radiocarbon dating. This has been through a combination of correlation of marine pollen and oxygen isotope records, a less certain correlation between adjacent marine and terrestrial pollen records and least certain pattern matching of terrestrial pollen records and the marine isotope stratigraphy (Kershaw and Nanson 1993, Kershaw and van der Kaars 2007). However, concern about proposed correlations has been expressed recently as the result of recent developments in dating methods including single-grain optically-stimulated luminescence and improved radiocarbon sample pre-treatment, which allow direct dating of older terrestrial sediments. Ages obtained by these methods demonstrate that assumptions about the dominance of northern hemisphere climate forcing, close positive relationships between temperature and precipitation variation, and the high impact of Aboriginal burning on the landscape, may not be tenable. Kershaw, A.P. and Nanson, G.C. (1993) The last full glacial cycle in the Australian region. Global and Planetary Change, 7: 1-9. Kershaw, A.P. and van der Kaars (2007) Pollen records, Late Pleistocene, Australia and New Zealand. In: Elias, S.A. (Ed.) Encyclopedia of Quaternary Science, Vol. 4. Elsevier, Amsterdam, pp. 2613-2622. Agricultural 'Origins' in the southern hemisphere DENHAM T.* School of Geography and Environmental Science, Monash University *tim.denham@arts.monash.edu.au Debate rages concerning the 'origins' of agriculture in the southern hemisphere, including South America, New Guinea and parts of Africa. The foci of debate concern whether agriculture emerged independently in each region or diffused from areas to the north, as well as whether the earliest forms of agriculture are associated with climatic stabilisation at the beginning of the Holocene. In this paper, the evidence for early agriculture is reviewed for each southern region and a framework advanced to understand the reasons for, and timing of, these major socio-economic transformations. Areal distribution of Late Holocene sediment proxies controlled by lake internal dynamics, Laguna Potrok Aike, Argentina KASTNER S.* (1) and SCIENCE TEAM (2) (1) Inst. of Geography, University of Bremen, Germany (2) * *steka@uni-bremen.de Situated in the dry steppe of Patagonia the maar Laguna Potrok Aike is a key terrestrial climate archive on the southern hemisphere. Interdisciplinary multi-proxy sediment studies document the sensitivity of this lacustrine archive to palaeoenvironmental variability and a close relation of the lakes hydrological budget to fluctuations of the Southern Hemispheric Westerlies. The spatial distribution of late Holocene sediments was analysed by a dense grid of gravity cores. Using XRF and magnetic susceptibility scanning data all cores were correlated and linked to an existing age model. Then multi-proxy analyses of six selected time intervals covering distinct lake level stages back to AD 1380 were conducted. The dataset was used to create distribution maps by point kriging. In addition to catchment characteristics, modern areal sediment distribution is strongly influenced by dominant westerly winds. This results in distinct littoral wave erosion and sediment focussing by wind-driven internal currents. The selected time slices infer modified depositional dynamics resulting from a variable lake level and changing wind patterns. Distribution patterns of the deep basin reveal intensified sediment relocation during lower lake levels and strengthened winds (~AD 1960). A homogeneous sediment distribution results from higher lake levels and weakened westerly winds (~AD 1800). *Science Team: C. Ohlendorf, T. Haberzettl, A. Lücke, N. Maidana, C. Mayr, F. Schäbitz, B. Zolitschka. Did climate change trigger hominid and cultural dispersion during the pleistocene? PARTRIDGE T.* UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG *tcp@iafrica.com Studies of Acheulean artefact assemblages in climatic zones of southern Africa ranging from sub-humid (the hominid sites of Gauteng) to semi-arid (the valley of the lower Vaal River) show that Early Acheulean hominids occupied the whole of this broad area. Various chronometric techniques were applied in an effort to determine the rate and pattern of dispersal of Acheulean technology across this extensive tract of the continental interior. Dating, using palaeomagnetic and isotopic techniques (U/Pb and 10Be/26Al burial dating), shows that Early Acheulean implements were used by hominids inhabiting these areas of southern Africa at the same time as their counterparts in East Africa: about 1.6Ma ago. This unexpected result implies very rapid rates of migration and cultural diffusion in the Early Pleistocene, not only in southern Africa but through the entire eastern hinterland of the African continent. In an attempt to explain these findings a model is presented which links orbitaly driven climatic fluctuations to the episodic, but rapid, westward and southward migration of hominid groups along valleys of rivers originating in areas of higher rainfall. This spread of Early Stone Age technology into ever more arid areas was apparently terminated by widespread climatic deterioration after about 1.2Ma. Geo-proxies of late Quaternary climate change in the southern African dryland interior: interpretations and issues THOMAS D.* and BURROUGH S. University of Oxford *david.thomas@ouce.ox.ac.uk Quaternary palaeoenvironmental/palaeoclimate reconstructions from the interior Kalahari are more spatially detailed, better dated, and span a longer time range than those of 30 years ago. Why then is the record not yet delivering a more robust picture of climate change in this region? We consider three explanations: 1) 'Geo-proxies' are the predominant source of palaeodata, based on interpretation of spatially extensive geomorphological features with complex accumulation histories. Their climatic, as opposed to environmental, significance is however often problematic and frequently confused in synthetic overviews. 2) In contrast, 'higher quality' or higher resolution local records are sometimes interpreted as records of spatially extensive conditions in the past, providing more spatially-coherent temporal interpretations. Yet this is counter-intuitive to the complexity in environmental systems today. 3) The quest to link regional to master records (ice and ocean cores) can force proxy interpretation, again underplaying the complex reality within the environmental system. Overall, there are not necessarily good or bad records of terrestrial palaeoenvironments in the Kalahari. Rather, there are records with different sets of information about past land surface, hydrological and climate conditions. The flaw lies in work that attempts to squeeze the same interpretations out of proxies that are markedly different in the contribution they make to unpacking late Quaternary change. High resolution records of Late Quaternary environments from Auckland maar lakes: Northern or Southern polar drivers? AUGUSTINUS P.* (1); D'COSTA D. (1); STEPHENS T. (1); COCHRAN U. (2) and SHANE P. (1) (1) School of Environment, University of Auckland (2) GNS Science, Lower Hutt, New Zealand *p.augustinus@auckland.ac.nz High-resolution Late Quaternary paleoclimate archives are preserved in the lake sediment records contained in several Auckland maar craters. Tephrochronology, AMS 14C and Ar/Ar -based chronostratigraphies were developed with several lakes containing laminated sediment records spanning much of the last glacial cycle. A multi-proxy approach was taken to construct a reliable record of local and regional paleoenvironments including: pollen and diatom paleoecology, environmental magnetism, grain size, XRF geochemistry, TOC, TN, TS, organic matter δ13C and δ18O in biogenic silica. Pollen and diatom analysis of records spanning the last ca 90 ka show marked vegetation changes that reflect orbital forcing, although diatoms suggest significant hydrological that are not reflected in the pollen. Reduction of forest with expansion of grass and shrublands at the start of the LGM (29 ka BP), is accompanied by cool, dry and windy conditions, although the situation is complex with multiple brief warmer phases punctuating the LGM. Post-glacial warming commenced ca 17.9 ka BP and is reflected in several proxies, although the pollen record does not reflect the marked changes displayed in many of the other proxies during the LGIT and Holocene. Some of the inferred environmental changes are similar to the nature and timing of short-duration events during the last glacial cycle from the North Atlantic region, although others appear to reflect a southern polar forcing. Late Quaternary environmental change and human occupation of the southern African interior BURROUGH S.* and THOMAS D. Oxford University *sallie.burrough@ouce.ox.ac.uk Geoarchaeological theory of human dispersal and evolution currently attaches great importance to climate and/or environmental variability, in terms of environmental constraints and opportunities for movement, dispersal and resource use by hominids. Refugia hypotheses predict a strong correlation between archaeological visibility and the hydrological status of lakes and rivers notably in recent work from east and central Africa (Barham, 2001, Basell, 2008). Ideas relating to environmental drivers of human evolution or dispersal (e.g. Jacobs et al., 2008) frequently utilize global scale records of climate change such as ice and marine cores to demonstrate environmental linkage, which sometimes may fail to capture the ‘real’ environmental components and complexity that actually drive human use of, and movement in, the landscape. In the Kalahari in central southern Africa, a greater understanding of landscape and hydrological dynamics, together with a rich archaeological record with strong landscape associations, offers the potential to robustly test these ideas on a regional scale. Late Quaternary history of the Westerly Wind Belt STUUT J.W.* (1) and CHASE B.M. (2) (1) Royal Netherlands Institute for Sea Research (2) Bergen University, Norway *jbstuut@nioz.nl The Southern Westerlies form the interface between the tropical and temperate systems on three of four southern hemisphere’s continents. At present, on each continent the Southern Westerlies leave a typical yet different imprint: South America, due to its geographical extent down to 60°S, registers the full 8° latitude seasonal swings between ~41 and ~33° South; In Africa the rain-bearing winds lead to a unique endemic vegetation by reaching the southernmost tip of the continent only in austral winter; In Australia the wind system influences only parts of the westernmost and easternmost bulges of land that reach southern latitudes of about 35°S, and is potentially influenced by the strong monsoon that develops over the northern part of the continent. In this paper we explore the extent to which the Southern Westerlies have played a role in late Quaternary environmental changes in the three aforementioned continents, the southern hemisphere, and the globe on timescales varying from decadal to orbital. We review data from various archives that register palaeo-environmental changes: marine and lacustrine sediment cores, speleothems and rodent middens, as well as ice cores. Southern connections and convergences: environment and cultural adaptations in the cool temperate Southern Hemisphere HABERLE S.* (1); ANDERSON A. (1) and WORKING GROUP E. (2) (1) Australian National University (2) Multiple Institutes *simon.haberle@anu.edu.au The evidence now available from archaeology, palaeoecology and ethnohistory in the cool temperate regions of the Southern Hemisphere reveals a surprising series of historical connections and adaptive convergences that warrant further exploration and explanation. Four major issues are identified as key to understanding cultural change in the southern cool temperate zone. (1) interactions between climate-biodiversity-people on different time scales, (2) prehistoric human settlement, (3) human interaction with the southern ocean, and (4) late dispersal of commensals. European arrival in the southern Pacific also resulted in the introduction of a range of plant and animal species which significantly affected social interactions, economies and environments in the region. The extent to which the regional archaeologies of the cool temperate zone disclose the influence of climate and palaeoecological convergences will be explored. The “Little Ice Age” in southern South America: Data and modelling MEYER I. (1) and WAGNER S.* (2) (1) MARUM - Center for Marine Environmental Sciences (2) Institute for Coastal Research, GKSS Research Cent *minka@marum.de The Litte Ice Age (LIA, ~ 1550–1800 AD) was one of the coldest periods since the Last Glacial. The LIA is well documented for the Northern Hemisphere, especially in Europe and North America. Many proxy reconstructions show a decline in temperature and more humid conditions during this period, followed by an abrupt rise in temperature to modern times. Although proxy records of this climatic anomaly for the Southern Hemisphere are scarce, the LIA seems to be a global event. However, the exact spatial and temporal occurrence is still a matter of debate. In this study a General Circulation Model (GCM) of the last 1000 years is used to investigate the hydrological changes over southern South America during the LIA. Results of the model simulation are compared with different proxy data from the southern South America ranging from geomorphological, lacustrine, pollen to tree ring reconstructions. Both reconstruction methods show a period of wetter conditions in south-eastern South America during the period of the LIA. Modelling results indicates large-scale atmospheric circulation changes of the Southern Hemispheric Westerlies (SHWs) over southern South America as one of the driving mechanisms for hydrological changes during the LIA. A shift of the SHWs during the LIA is also supported by different proxies. They show wetter conditions and cooler temperatures in south-eastern South America accompanied with drier and warmer conditions to the north. The Medieval Warm Period and Little Ice Age in the New Zealand Subantarctics MCGLONE M.S.* (1); WILMSHURST J.M. (1); TURNEY C.T.S. (2) and MCNEILL S. (1) (1) Landcare Research, Lincoln, New Zealand (2) University of Exeter, United Kingdom *mcglonem@landcareresearch.co.nz There has been a long-standing debate as to the magnitude and global reach of the Medieval Warm Period (MWP: 9th – 13th centuries) and the Little Ice Age (LIA: 15th – 19th centuries). Evidence for these episodes has been particularly diffuse in the Southern Hemisphere. Recent work (Schaefer et al. 2009. Science 324:622-625) has shown that glacier fluctuations in the Southern Alps of New Zealand were neither in phase or strictly antiphased with those from the Northern Hemisphere. Subantarctic Campbell Island (52ºS; 113 km2) lies far to the south of the New Zealand mainland, and at the southern limit for woody vegetation in this sector of the Southern Ocean. Pollen-based records of Holocene treeline position, summer temperature change, and peat growth from a total of 10 peat cores spanning the altitudinal range (0-570 m) on this small island show fluctuations consistent with global MWP and LIA events. These temperature-related vegetation changes on Campbell Island bear less relationship to glacier fluctuations in the Southern Alps of New Zealand suggesting the Southern Ocean is approximately in phase with the Northern Hemisphere on these timescales. Moreover, viewed against the whole Holocene record, neither the MWP nor LIA stand out as unusual, as there have been more than 10 prominent cold or warm events on Campbell Island since 11 500 BP. The role of fire and climate in the demise of the megafauna?: Lynch's Crater. northeast Queensland, Australia RULE S.* (1); JOHNSON C. (2); HABERLE S. (1); KERSHAW P. (3) and TURNEY C. (4) (1) Australian National University, ACT, Australia (2) James Cook University, Queensland, Australia (3) Monash University, Victoria, Australia (4) Exeter University, UK *susan.rule@anu.edu.au Lynch’s Crater in northeast Queensland has been influential in the debates over the time of arrival of Aboriginal people on the continent and degree of impact on the landscape through their burning activities. This initial period of arrival, 45-50 ka, also saw the extinction of Australia’s Pleistocene megafauna which would have had a major impact on vegetation structure and composition. A high resolution palaeoecological study covering just over 50 thousand years was undertaken to see whether it was possible to separate natural fire occurrence from anthropogenic, while dung fungi, especially Sporormiella, was used to identify biomass quantity on the swamp surface. Although results suggest that climate is the prevailing influence, at times fire patterns do suggest an anthropogenic source and while biomass quantity varies with plant structural change the local hydrological conditions may influence the composition and overall dynamics of the swamp environment. Toward an integrated understanding of patterns & controls of climate variation in tropical South America at orbital to multi-decadal scales FRITZ S.* (1) and BAKER P. (2) (1) University of Nebraska (2) Duke University *sfritz2@unl.edu The nature of Quaternary climate variation in tropical South America has been debated for over half a century, particularly since Haffer proposed that high biodiversity may have been driven by massive precipitation variability. In this talk, we review recent advances in our understanding of the patterns and controls of climate variation in tropical South America based on late Quaternary reconstructions of paleoprecipitation (speleothems) and water balance (lake levels). We posit that low-frequency variation of South American Summer Monsoon (SASM) precipitation is forced by a combination of regional summer insolation and the north-south hemispheric Atlantic SST gradient. NH stadial events are present in records throughout the neotropics, including regions influenced by the SASM. This suggests that during glacial times, North Atlantic forcing was equal to or greater than Pacific ocean and precessional forcing. The available high-resolution Holocene records also suggest that precipitation variation at multi-decadal to-centennial scales is forced by Atlantic SST change. Thus, although Atlantic variability is not a dominant factor in forcing tropical South American climate variability during the instrumental period, the evidence suggests a much more important role for the Atlantic in forcing climate changes in tropical South America in the past. This results, because the magnitude of SST anomalies in the past is considerably greater than the inter-annual anomalies of today. Conservation and sustainable management of Southern Hemisphere temperate indigenous grasslands: developing a strategic plan. Climate change, fire and conservation management in Australia’s alpine grasslands WILLIAMS R.J.* (1); HOFFMAN A.A. (2); CAMAC J.C. (2); WAHREN C. (3) and MANSERGH I.M. (4) (1) CSIRO Sustainable Ecosystems, Australia (2) University of Melbourne, Australia (3) La Trobe University, Australia (4) Vict. Dept Sustainability & Environment, Australia *dick.williams@csiro.au Global warming threatens alpine ecosystems worldwide. Australia’s alpine landscapes face the twin stressors of a warming and drying climate and altered fire regimes. Most of Australia’s alpine grasslands are within protected areas, and in this paper we explore the implications of such change for their conservation management, drawing on long-term monitoring and a fire x warming experiment. Warming interacts with fire in complex ways, with many species-specific effects on phenology, growth and adaptive potential. Common native species have shown genetically-based and/or plastic responses to warming, and may show compensatory responses to warming to different extents. These findings indicate a significant, but varied, capacity to adapt to climate change. The potential resilience of alpine grasslands to warming suggests that the diversity of the flora may not decline rapidly in the face of warming. However, the enhanced potential for shrub invasion of grasslands under warming scenarios may be of more immediate concern to managers. Given that shrubs are more combustible than grasses, and the projected increase in fire weather danger in south-eastern Australia in the coming decades, management of fire regimes especially within the surrounding forested foothills, to reduce the incidence of fire in the alpine region, is critical. Monitoring of long-term trends in vegetation state is also a critical component of the management of alpine landscapes in the face of unpredictable change. Conservation and sustainable management of South American indigenous temperate grasslands: issues and options MICHELSON A.V.* International Union for Conservation of Nature *andrea_michelson@yahoo.com In South America, the temperate grasslands eco-regions (Paramos, Puna, Pampas and the Patagonian steppe) occupy around 2,3 million sq.km. They are distributed from the southern edge to the northernmost tip of the continent, in 10 countries. These grasslands provide essential ecosystem goods and services to millions of people living in urban and rural areas, such as water (for urban use, irrigation and hydropower generation), food (meet, milk and crops), carbon sequestration,etc. They are considered as important ecosystems from a production perspective. However, generally neglected is the fact that they are also important from a socio-cultural and environmental viewpoint. From a regional perspective, the challenge is to coordinate conservation efforts of different stakeholders, organizations and sectors within and among eco-regions; raise awareness of decision makers; strengthen national and international policy; implement financial mechanisms to support for long term conservation commitments; integrate grassland conservation with food security and poverty reduction goals; and improve mitigation and adaptation measures to cope with climate change. To tackle these issues, the Temperate Grasslands Conservation Initiative (WCPA/IUCN) in South America, in collaboration with key regional partners, has developed a portfolio of projects that put forward an integral strategy to increase their protection status and promote the widespread use of sustainable manageent practices. Conservation problems in Cordoba mountain grassland ecosystems CINGOLANI A.M.* (1); GIORGIS M.A. (2) and RENISON D. (1) (1) Universidad Nacional de Córdoba - CONICET (2) CONICET *acingola@com.uncor.edu The present treeline in the Córdoba mountains (central Argentina) is ca. 1300 m asl, and has traditionally been considered as climatically determined. Grassland and rocky habitats dominate the landscape above the treeline (up to the highest summit at 2800 m asl) coexisting with small patches of Polylepis australis woodlands. These woodlands are restricted to deep ravines and rocky outcrops, habitats that were traditionally considered as more favourable due to their microclimatic conditions. In opposition to this view, our studies suggest that if fire and herbivory were excluded, climate would not restrict tree development. In this scenario, an almost continuous woodland matrix could dominate the landscape up to the summit. The composition of such matrix would be influenced by the present day scarce native propagule sources (including both high and low mountain tree species), and the abundant propagules of alien invasive species. Supporting our idea, a recent world-wide study determined that growth-season mean temperatures of most tree-lines in the world are between 6 – 7 ºC, far less than those found in our mountains at the highest altitudes. As livestock is now the main herbivore in the area, and fires are in almost all cases human caused, we sustain that our present grasslands are at a great extent anthropogenic, and could potentially be managed as a woodland ecosystem, where grassland species survive in patches within a woodland matrix. Differing perspectives behind the meaning of ecologically sustainable products: opportunities in Patagonian grasslands for reducing disparit NOGUéS A.* Sustainable Grazing Strategy, Patagonian Grasslands Conservation Project, Southern Andes, The Nature Conservancy *anogues@tnc.org In Patagonia, many wool and lamb producers identify their products as “natural”, “ecological”, or “sustainable”. This is driven mainly by the fact that the primary production of forage species depends mostly on native vegetation rather than introduced species and chemicals are generally not used on these native grasslands. In many cases, the wool and lamb meat produced on the Patagonian steppe and Low Monte are commercialized with marketing efforts that emphasize the presence of these natural grasslands as an indication that the product is ecologically sustainable. However, moderate to severe cases of desertification in the region have been documented and are likely to face a negative impact with climate change. The Nature Conservancy is using the best available science and working with local stakeholders to define management models that include biodiversity and freshwater conservation needs and yield quality products without contributing to desertification. With these science-based models, the tools necessary to define “ecologically sustainable” products will be available for consumers who demand specific information regarding the production standards reflected in “natural”, “ecological”, or “sustainable” products. In this way, market forces may become a driving force for the implementation of specific and science-based ecologically sustainable production standards in Patagonia. How will Central Andean grasslands react and adapt to combined land use and global changes? BECK S. (1); LEDEZMA J.C. (2); IBáñEZ M. (3); YAGER K. (4) and HALLOY S.* (3) (1) Herbario Nacional, Universidad Mayor de San Andrés (2) Conservación Internacional (3) The Nature Conservancy (4) Yale University *shalloy@tnc.org The central Andes comprise the largest high altitude plateau after Tibet. The area is highly sensitive to climate variability and change and is home to rich variety of flora and fauna with high level endemisms. The densely populated northern reaches of the altiplano have coevolved with intensive human use for millennia, developing into a highly structured human-natural landscape. In contrast the dry southern reaches include some of the most extensive unpopulated areas in the world. The central altiplano exhibits two tiers: the larger one expanding around 3600-4000 m, and a second, higher, altiplano above 4600 m. The impacts, resilience, and adaptation to climate change on the altiplano (puna, high Andean, and southern paramo grasslands) are highly site-dependent. Reactions thus require local knowledge, integrating multidisciplinary and multiscale knowledge with participation from local communities. We report on some of the advances in this area, including the vision of the altiplano as a transboundary climate refuge. Unlike most cone-shaped mountains, the distribution of altitudinal tiers in the central Andes has a remarkable toadstool form, with habitat area increasing with altitude over 70% between 3100 and 3500 m. Thus, the altiplano may become a haven for species and land uses currently practiced lower down. Conversely, species and practices of the altiplano itself may be particularly highly threatened as their potential habitat decreases even more dramatically. Oceanic grasslands in a sea of troubles: why New Zealand grasslands are different, and how they are changing LEE W. (1); MCGLONE M. (2); ROGERS G. (3); PIRIE M. (4) and LLOYD K.* (5) (1) Landcare Research, Dunedin, New Zealand (2) Landcare Research, Lincoln, New Zealand (3) Department of Conservation, Dunedin, New Zealand (4) University of Stellenbosch, South Africa (5) Wildlands Consultants, Dunedin, New Zealand *Leew@landcareresearch.co.nz The origin, diversification, drivers, and spatial patterns of New Zealand grasslands provide clear constraints for the persistence of these ecosystems. The grasslands are dominated by Danthoniiae (Chionochloa, Rytidosperma) and Poeae (Poa, Festuca) that arrived during the Cenozoic. They comprise species which have radiated ecologically from generalist taxa during the Pleistocene in response to increasing specialisation along temperature and edaphic gradients in non-forest habitats that persisted through glacial cycles. Perennial and caespitose growth forms predominate from maritime to alpine zones, and C4 and annual grasses are absent. Grassland area varied considerably, depending on environmental factors (e.g. temperature, moisture, soil nutrient status) and disturbance (e.g. colluvial/alluvial inundation) limiting scrub and forest. Fire and mammalian herbivory, major drivers of grasslands elsewhere, only became important following human settlement ca 800 years ago. Some grassland species benefited from fire (C. rigida, C. rubra) and the competitive release provided by grazing (e.g. F. novae zelandiae, P. colensoi). However the combination of overgrazing, frequent burning, and cultivation have decimated indigenous grasslands. Processes and pathways causing grassland formation and degradation are different from those required for grassland restoration, and may not be achievable in the absence of suitable grass seed sources, and the presence of herbaceous and woody weeds. Potential impacts of climate change on humid tropical alpine regions CUESTA F.* (1); BUYTAERT W. (2) and TABON C. (3) (1) CONDESAN (2) Imperial College London, UK (3) Universidad Nacional de Colombia *F.Cuesta@cgiar.org Humid tropical alpine environments are crucial ecosystems that sustain biological processes, carbon storage, and surface water regulation of tropical mountain regions. They are identified as one of the most vulnerable terrestrial ecosystems to global environmental change. Climate change will displace ecosystem boundaries, and strongly reduce the total area of tropical alpine regions. Displacement, and increased isolation of remaining patches will induce species extinction and biodiversity loss. Species that are likely to suffer most are those that have a C3 metabolism pathway, poor dispersal capabilities, long generation time, low genetic plasticity, and narrow climatic niche amplitude. Dryer and warmer soil conditions will cause a faster organic carbon turnover, decreasing the carbon storage capacity of the soils. Since many soils contain elevated amounts of organic carbon, it is unlikely that an increase of above-ground biomass will be able to offset soil carbon loss. Therefore a net release of carbon to the atmosphere is expected. Changes in precipitation patterns, increased evapotranspiration, and alterations of the soil properties will strongly affect water supply. Promoting Public-Private Partnerships as a means to sinergize community-based grassland conservation in Patagonia BELTRAN J.* The Nature Conservancy *jbeltran@tnc.org An attempt to adapt the Public-Private Partnership concept (PPP) to enhance the conservation situation of Patagonian Grasslands in Argentina is described. A PPP tipically consists of a government service or private business venture funded and operated through a partnership of government and private associates. The service or venture is not restricted to any particular class, and so it may include disciplines like nature conservation. In such cases, the PPP mission could be bringing public, private and philantropic partners together to fund and manage a joint effort to protect a continuous area of functional ecosystems, and preserve the environmental services that are provided by them. An approach like this seems appropriate as a means to bridge the conservation gap that affects grassland areas across Patagonia, specially considering the dimension of the gap itself, the private land tenancy that predominates across the region, and the interest of government agencies, ranchers, cattlemen associations, NGOs, and other actors to become involved in a synergistic conservation initiative. An ideal configuration of a PPP for furthering conservation action of Patagonian Grasslands is delineated, paying attention to the institutional arrangements that may incentivize a greater permanent contribution of land with conservation value from the community of ranchers. Temperate deserts and semideserts in the Southern Hemisphere: An historic perspective of land degradation due to rapid livestock introductio BRAN D.* INTA EEA Bariloche. Area de Recuros Naturales *dbran@bariloche.inta.gov.ar Vast arid and semiarid regions of Argentina, Chile, Australia and South Africa are occupied by extensive sheep breeding systems which provide wool to the international market. These systems were developed and rapidly expanded during the XIX century, on relatively virgin grasslands which to the time were inhabited by aboriginal hunters and gatherers. The relatively late occupation of these territories, after the industrial revolution, allowed the massive introduction of sheep during a surprisingly short period. For example, in Patagonia, only 25 years after the introduction of the activity, sheep reached the number of 22.000.000, twice than the present quantity. Considering the large areas involved, and the short period during these changes occurred, is not surprising that the impact on the grassland ecosystems was dramatic. The objective of this presentation is to discussed similitudes and differences of these processes between countries members of SC and promote the following questions: How much of the degradation we perceive today was generated in that initial period of introduction and what was the impact on these unique indigenous grassland biotas? Land degradation process may have been stabilized or is it continuing? Also, what are their possible impacts on the ecological and evolutionary processes, particularly in a scenario of climatic change?. The conservation and protection of the world's indigenous temperate bgrasslands: Priorities for the Southern Hemisphere MARK A.F.* (1) and HENWOOD B. (2) (1) Botany Dept, University of Otago, Dunedin, New Zealand (2) Parks Canada, Vancouver, Canada. *amark@otago.ac.nz Temperate indigenous grasslands, one of the world’s great biomes, are now the most altered terrestrial ecosystem and the most endangered on most continents. More than half their area has been irreparably lost to other land uses and they have the lowest level of protection of the 14 major terrestrial biomes. Only 5% has protected status. Much effort is required to increase their protection if they are to achieve their rightful place in the world’s protected areas system. Achieving at least 10%, as recommended by the CBD, is a great challenge for an ecosystem that is now so altered. Further, to maintain biological diversity and ecosystem health beyond protected areas, sustainable land management must be implemented if these grasslands are to continue to provide the range of social and ecological services necessary for human well being. Southern Hemisphere grasslands; the pampas and campos, páramo and puna, and Patagonian steppe in South America; tussock grasslands of SE Australia and New Zealand; and southern African veld, all have variable levels of disturbance and protection. We review their current status, both globally and regionally, and suggest priorities for increased protection. We also discuss the Temperate Grasslands Conservation Initiative (TGCI), designed to facilitate international communication, collaboration and commitment, and develop a strategy to achieve meaningful protection for, and sustainable use of, the world’s indigenous temperate grasslands. The role of fire in the ecology of southern African grasslands BOND W.; GRAY E. and ZALOUMIS N.* University of Cape Town, South Africa *William.bond@uct.ac.za The highveld grasslands of South Africa are dominated by C4 grasses, despite growing in relatively cool summer rainfall regions. They are not climatically determined and often form mosaics with forests. Similar upland grasslands are common in the tropics and sub-topics of the southern continents and in India. Southern African grasslands are very rich in forb species with many endemics. Most cannot tolerate shade and are eliminated by encroaching scrub forest or under conifer plantations. Many forb species have large underground storage organs that allow rapid sprouting after fires. While very tolerant of frequent fires, such forbs are eliminated by ploughing or shading. They are very poor colonisers and absent from secondary grasslands. C4 grasslands appear to burn more frequently, and support more fire-dependent species, than C3 grasslands. C3 grasses are expected to replace C4 under high atmospheric CO2 in the coming century with largely unexplored consequences, one of which may be reduced fire frequencies. The role of forest managers in conservation of native grasslands in northwest Tasmania DUNCAN F.* (1); GILFEDDER L. (2) and ONFRAY R. (3) (1) Forest Practices Authority (2) Dpt of Primary Industries, Water, Parks & Environm (3) Gunns Forest Products *Fred.Duncan@fpa.tas.gov.au Native grasslands cover 6500 ha in montane areas of NW Tasmania. They are dominated by Poa spp, occur in mosaics with moorlands, peatlands, rainforest, eucalypt forest and plantations, and are maintained by fire, frost and marsupial browsing. Surveys in the 1980s identified the most significant grasslands – many are managed by forestry companies. Since then, conservation partnerships have been developed between researchers, government agencies and forest managers. About 25% of the NW grasslands are now reserved on public and private land. Outside reserves, about 40 grasslands (>50% of the grassland area) are actively managed for conservation by forestry companies. Landscape-level planning includes linking grasslands and other native vegetation. Management of individual grasslands includes mosaic burning (4–9 yr intervals) to maintain species' community diversity and habitat of threatened species (e.g. Oreixenica ptunarra – a butterfly whose larvae feed on Poa). Weed control has been implemented. Some plantations have been allowed to regenerate to grassland after logging. Conservation management of the NW grasslands has been refined through research, monitoring and use of spatial technology. It is supported by legislation to protect threatened species/communities; forest industry certification and education programs. Such multi-faceted approaches may be relevant to regions, including Patagonia, where grasslands, native forest and plantations co-occur on a range of tenures. Towards the conservation of Southern Hemisphere temperate grasslands: A South African perspective CARBUTT C.* Ezemvelo KZN Wildlife *carbuttc@kznwildlife.com For South Africa to effectively contribute to the conservation of temperate grasslands (the expansion potential of temperate grasslands is fairly limited given that South Africa has been assessed as being a moderately modified and fragmented landscape), each relevant province should generate a scientifically explicit protected areas expansion strategy, identifying expansion opportunities and the mechanisms by which they should be secured. The provinces of Mpumalanga and KwaZulu-Natal have identified an additional 577,500 ha and 386,000 ha of temperate grassland for conservation respectively. The Sub-escarpment grassland bioregion, of which a large proportion occurs within the province of KwaZulu-Natal, has been identified in South Africa's National Protected Area Expansion Strategy (NPAES) as requiring critically urgent attention; this is the most threatened temperate grassland bioregion in South Africa. This paper addresses progress made since the Hohhot meeting, focussing specifically on the additions of new areas of temperate grassland under protection since 2008; the prioritization exercises using systematic conservation planning to identify the next suite of temperate grasslands that require protection (mostly making use of the stewardship and land acquisition options), as well as potential funding opportunities to bankroll these initiatives. Sharing Gondwanian knowledge and experience for capacity building and improvement of regional and global invasions management. Beaver eradication, the necessary first step to restore southern South American ecosystems MENVIELLE M.F.* (1); MALMIERCA L.; RAMADORI D. (2); SAAVEDRA B. (3); SAUNDERS A. (4); SCHIAVINI A. (5) and SOTO VOLKART N. (6) (1) National Parks Administration, Argentina (2) National Fauna Direction, Environmental and Sustainable Development National Secretary, Argentina. (3) Wildlife Conservation Society, Chile (4) Landcare Research, New Zealand (5) National Scientific and Technical Research Council, CONICET, Argentina (6) Agricultural and Livestock Service, SAG, Chile *fmenvielle@apn.gov.ar Tierra del Fuego contains unique environments, almost untouched by humans. Southernmost distribution of forests and > 5% of world’s bryophytes are found here. Regardless of its remoteness, these environments are affected by global threats, like invasion of alien species, of which beavers (Castor canadensis) are the most important. Beaver engineering affects austral biodiversity at all levels, as well as the ecosystem structure and processes that help maintain this biota. Initially confined to the Archipelago, beavers reached the South American continent, scaling their ecological and economic impacts to a huge new dimension. Our aims are to describe the process by which, as a result of an encouraging decision, the governments of Argentina and Chile agreed on the implementation of a Bi-National beaver eradication Project with the objective to stop invasion to the continent and start restoration of these ecosystems, and to share the results of project planning. The challenges resulting from this decision are presented, the most important of which is to adopt the right vision required for any eradication project. Other major challenges include common actions of Argentineans and Chileans with the community of international experts in eradication, now strongly developed in the Southern cone; learning about the strategic implementation of complex projects; and the development of local capacities including science, management, etc., required to achieve this ambitious goal. Biological control of Gorse Ulex europaeus in New Zealand: Lessons for other countries? PAYNTER Q.*; FOWLER S.; GOURLAY A.H.; PETERSON P. and WINKS C. Landcare Research New Zealand *paynterq@landcareresearch.co.nz Objectives The European woody shrub gorse Ulex europaeus, shares many ecological similarities with broom Cytisus scoparius and is also an invasive introduced weed in temperate South America, Australia and New Zealand. Like broom, a seed-feeding beetle Exapion ulicis has been introduced to control gorse in New Zealand as well as in Australia and Chile. This agent, however, has been assumed to have little impact of gorse populations because autumn and winter flowering gorse escapes seed predation. Methods We reviewed the recent global literature describing advances in the understanding of the pollination and flowering phenology of gorse and of the impacts of biological control of gorse in New Zealand. Results We develop a conceptual framework that explains how E. ulicis may have resulted in selection pressures that favours winter-flowering gorse plants, while the broom seed-beetle Bruchidius villosus selects for broom plants that produce small seeds. Conclusions The implications of selection for winter flowering, the prospects for successful biocontrol of gorse and future research priorities are discussed. Conifer invasion in Gondwana: different regions give lessons in different topics NUñEZ M.* (1); PAUCHARD A. (2); BUSTAMANTE R. (3); SARASOLA M. (4); PEñA E. (2); LEDGARD N. (5); RAFFAELE E. (6); RELVA M.A. (6); RICHARDSON D.M. (7); VAN WILGEN B. (8); WILLIAMS M. (9); ZILLER S. (10) and SIMBERLOFF D. (11) (1) University of Tennessee (2) Facultad de Ciencias Forestales Universidad de Concepción, Chile. (3) Institute of Ecology and Biodiversity, University of Chile, Chile. (4) Coordinador del Área Forestal, Estación Experimental Agropecuaria, INTA Bariloche, Argentina. (5) Scion, Fendalton, Christchurch, New Zealand. (6) Universidad Nacional del Comahue, Laboratorio Ecotono, Argentina. (7) Deputy Director, Centre for Invasion Biology, Stellenbosch University, South Africa & Member IUCN Species Survival Specialist Groups on Conifers and Invasive Species. (8) Chief Forest Ecologist, CSIR, South Africa. (9) Pest Management Unit, Department of Environment and Climate Change (NSW), Hurstville, Australia. (10) Coordinator South America Invasive Species Program, The Nature Conservancy, The Hórus Institute for Environmental Conservation and Development, Brazil. (11) Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA. *mnunez@utk.edu Exotic conifers have been planted throughout the world and many of them have become highly invasive. This is especially true in countries of the southern hemisphere where the forestry industry relies heavily on exotic species and where conifer invasions have been reported in numerous countries. Histories of conifer plantations and management of invasions differ greatly among regions of the southern hemisphere. In some cases the same species has been planted in different time periods, numbers, and ecosystems. This provides a unique opportunity to deeply understand the problems and mechanisms behind tree invasion. Countries like South Africa and New Zealand have a long history of invasions and management. On the other hand, countries in South America have a much younger history of plantations and invasions have just recently been recorded. In this context, we have formed the Southern Hemisphere Network on Conifer Invasions, where researchers throughout the world are interacting and producing basic information on these phenomena. Its goal is to facilitate different regions sharing ideas and, hopefully, preventing similar problems that have already occurred elsewhere. There are many difficulties in organizing this type of networks, such as communication and finding funding to organize meetings, but there are also many benefits that contribute to a better understanding of the global phenomenon of conifer invasion. Factors affecting the invasive ability of Scotch broom Cytisus scoparius in exotic habitats. PAYNTER Q.* (1); BUCKLEY Y. (2); MAIN A. (3); FOWLER S. (1) and GOURLAY A.H. (1) (1) Landcare Research New Zealand (2) University of Queensland/CSIRO Sust Ecosystems (3) University of Queensland *paynterq@landcareresearch.co.nz Objectives The European shrub broom Cytisus scoparius is invasive in many regions, including temperate South America and Southern Africa. In Australia and New Zealand (NZ), a seed-beetle Bruchidius villosus has been introduced to control broom. We predicted that the invasive mite Varroa destructor, which causes honeybee decline, may enhance broom biocontrol in NZ. Methods We measured pollination rates and broom seed rain and the impacts of B. villosus in NZ and we modelled the potential impacts of B. villosus and reduced pollination on broom abundance. Results Broom seed rain ranged from 59–21,416 seeds m-2 from 2004 to 2008, and was closely correlated with visitation frequency of honeybees Apis mellifera and bumblebees Bombus terrestris. Bruchidius villosus destroyed an average of 73% of seeds at the earliest release sites. Simulation models indicated that decreased pollination through an absence of honeybees may reduce broom seed set to levels at which B. villosus can be effective at reducing broom populations. Preliminary data indicate that B. villosus may also impose a selection pressure that favours broom plants that produce small seeds. Conclusions Broom seed set is highly reliant on honeybees. Improved management of commercial beehives could be used as part of a successful integrated broom management programme at many sites in NZ and elsewhere. By selecting for small seeds B. villosus may reduce broom seedling competitiveness and thus broom invasiveness. Invasion and spread of the German wasp ( Vespula germanica ) in the Southern Hemisphere. Same invader, same invasion process? CORLEY J.* (1); BEGGS J. (2); SACKMANN P. (3) and MASCIOCCHI M. (1) (1) INTA Laboratorio de Ecologia de Insectos, Argentina (2) School of Biologica Sciences. Tamaki Campus, University of Auckland (3) Laboratorio Ecotono-INIBIOMA-CRUB, Argentina *jcorley@bariloche.inta.gov.ar Our aim is to contribute to increase our understanding of animal invasions by comparing the invasion process (and consequences) of the same species in biologically similar ecosystems. A review of the invasion history of Vespula germanica, the german or yellowjacket wasp in Argentina and New Zealand will be presented. We will then analyze and compare the invasion process (namely spread) in both regions focusing on the factors (e.g.: climate matching, biotic resistance, containment or control plans) explaining observed differences and similarities. Finally we will present information on the consequences of the invasion by this social wasp in both regions. Phylogeography of native and invasive Hieracium spp. (Asteraceae) herbs from southern Argentina and Chile, implications BRAUN K.* (1); MIROL P. (1); PIGNATARO G. (1); COLLANTES M. (1) and SIMON P. (2) (1) Museo Argentino de Ciencias Naturales (2) Museo de La Plata *k.braun@hotmail.com Hieracium spp. weeds have invaded several gondwanic countries, producing severe ecological and economical damage. To explore hybridization, geographic races, and genetic variability of Hieracium spp. species from southern Argentina and Chile, we sequenced 650 base pairs of the nuclear ribosomal DNA ITS sites from 53 individuals belonging to invaders H. pilosella (n=31) and H. praealtum (n=14), and to natives H. cff. patagonicum (n= 3) and H. chilensis (n=5), and we included secuences from New Zealand and from the gene bank (natives H. antarcticum, and H. patagonicum). Different phylogenetic trees showed a well supported clade including the exotic species as sister groups, and another clade for all native species. H. cff. patagonicum (a species attacked by an insect candidate for biocontrol of exotic Hieracium species) individuals had the exact same sequence as four of the individuals of H. praealtum . Though a wide latitudinal was studied, intraspecific genetic distances were very low (H. pilosella and H. praealtum: 0.0024, H. chilensis: 0.0032) and genotypes differed by only one mutation. There was no geographic structure in any of the examined species, suggesting asexual-apomictic reproduction, a low mutation rate, and no hybridization among species, and encouraging the use of biological control to manage these invasions, an effective-in-the long-term and environmentally friendly method. Pine invasion in South America: patterns, process, and lessons to be learned. Conifer Invasions in southern Chile: History, patterns and impacts PAUCHARD A.* (1); LANGDON B. (1) and PEñA E. (2) (1) Facultad de Ciencias Forestales, Universidad de Concepción. Instituto de Ecología y Biodiversidad, Santiago, Chile (2) Facultad de Ciencias Forestales, Universidad de Concepción *pauchard@udec.cl Exotic conifers have been extensively used for forestry plantations and have become invasive in several natural ecosystems. During the 20th century, the Chilean government and forestry companies began massive reforestation programs using fast-growing introduced species to stop soil degradation, even in protected areas. Industrial plantation began in the late sixties and has its largest boom in the eighties. Pinus radiata was the most planted species, especially in water stressed areas. However, in southern areas, Pinus sylvestris, Pinus ponderosa, Pinus contorta and Pseudotsuga menziesii were initially introduced in trial plots and then in small-scale industrial plantations. We have studied the spatial patterns of invasion of some of these species in natural ecosystems. For P. contorta, P. sylvestris and P. menziesii, we studied the Coyhaique area, in the Chilean Patagonia. The three species are naturalized and both P. sylvestris and P. contorta are invading the area. Regeneration of P. contorta advances up to 3 km in less than 20 years. For P. menziesii, we evaluated stands adjacent to the native forest in the Araucanía and Los Ríos Regions. P. menziesii regeneration was concentrated in the first few meters from the plantation and the species is naturalized in 5 of the 6 study sites and invading in two. We are now addressing the mechanisms of invasions and the potential impacts that conifer invasions can have on our native biota. Funded by ICM P05-002 and PFB-23. Ecological determinants of Pinus radiata invasion in forest fragments of the Maulino forest, central Chile BUSTAMANTE ARAYA R.O. (1); DE LA FUENTE P.L. (2) and SAN MARTíN J.* (2) (1) University of Chile, Institute of Ecology and Bi (2) University of Talca *rbustama@uchile.cl Pines are regarded invasive species worldwide. Vast areas of the South hemisphere have been used for pine plantations. In this presentation, we examine the determinant of Pinus radiata invasion in a fragmented forest of Central Chile. Considering that this tree is a colonizer, shade-tolerant species, we argue that the availability of light, regardless other local and landscape attributes should be the main driver of pine invasion. We have assessed patterns and processes of pine invasion in the Maulino forest, a fragmented forest of Central Chile. Either observational and experimental evidences strongly suggest that structure of the canopy is the main driver of pinus invasion. Pines are absent in the interior of well conserved forests but they become abundant when the cover is reduced significantly; at microsite scale, the cover and the depth of the litter were negatively correlated with pine density. We show unequivocal evidence of pine invasion in Chile. The cover seems to be the most important factor to explain pine density either at local and at landscape level. Measures to prevent pine invasion should be oriented to the conservation of remnant forest with a well conserved canopy. Project ICM P05 -002 and PBCT 034/2006. Fire promotes exotic pine invasions in Patagonia RAFFAELE E.* (1) and ENESTROM J. (2) (1) Universidad del Comahue (2) Lund University *estelaraffaele@yahoo.com.ar Pines have caused problems by invading natural communities in many places, especially in the southern hemisphere, when planted outside of their natural range for commercial forestry. In Patagonia, several pine species including species with adaptations to cope with and regenerate vigorously after fire, have been planted in areas that were formerly open woodland or steppe, where lack of fuel continuity was an important limitation to fire spread. Natural wildfires have been a recurrent disturbance for as long as there have been humans in this region. The fires are intensified in areas with poorly managed pine plantations where the increased fuel load creates fast spreading crown fires. We studied the establishment of pines after fires, suspecting that the establishment success of pines both inside and outside of the plantations would be high. Field studies were conducted in 17 sites where pine plantations had been burnt in fires between 1985 and 2002. We recorded pine establishment inside and outside burnt plantations to study the pine establishment after fire in 2002 and 2009 at the same sites. In 2002 establishment of pines outside the old burnt plantations was found only in two sites. However, in 2009 we recorded high densities of pines outside in at least 10 sites. Inside the old plantations the establishment of pines was much higher than outside of the plantations, both in 2002 and in 2009. We concluded that there is a risk that pines will become invasive in Patagonia. Introduced conifers in south america: lessons from the other Southern hemisphere regions SIMBERLOFF D.* (1); NUñEZ M. (1); LEDGARD N. (2); PAUCHARD A. (3); RICHARDSON D. (4); SARASOLA M. (5); VAN WILGEN B.W. (6); ZALBA S.M. (7); ZENNI R.D. (11); BUSTAMANTE R. (8); PEñA E. (9) and ZILLER S.R. (10) (1) University of Tennessee (2) SCION (3) Universidad de Concepcion, IEB (4) Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Matieland (5) Instituto Nacional de Tecnología Agropecuaria, INTA – EEA Bariloche, Bariloche (6) Centre for Invasion Biology, CSIR Natural Resources and the Environment, Stellenbosch, South Africa (7) GEKKO, Grupo de Estudios en Conservación y Manejo,Universidad Nacional del Sur, Bahía Blanca, Argentina (8) Instituto de Ecología y Biodiversidad (IEB), Santiago-Universidad de Chile, Departamento de Ciencias Ecológicas, Santiago, Chile (9) Universidad de Concepción, Facultad de Ciencias Forestales, Concepción (10) Horus Institute for Environmental Conservation and Development, Florianópolis, Brazil (11) The Nature Conservancy, South America Invasive Species Program, Curitiba *dsimberloff@utk.edu Introduced conifers have invaded in South Africa, Australia, and New Zealand, where extensive plantations were established ca. 50-80 years earlier than in South America. A group of ecologists convened in Bariloche in 2007 to seek insights from these invasions relevant to prospects for South America. In each region, small-scale plantings were largely harmless, but large plantations were followed after a lag of ca. 20-30 years by worrisome invasions. In other Southern Hemisphere regions, impacts of invading conifers include replacement of grassland and shrubland by conifers, alteration of fire and hydrological regimes, modifications of soil nutrients, and changes in biotic communities. The area devoted to non-native conifers is already large in Chile, growing rapidly in Argentina and Brazil, and substantial in Uruguay. Several published reports from Argentina and Chile report certain conifer invasion impacts not unlike those of the other continents, but on a smaller scale. Such impacts are beginning in Brazil as well. The sheer mass of non-native conifers in South America means that propagule pressure is intense, and this has been important in conifer and other invasions. Regulations to delay conifer invasion in South America are weak and piecemeal. In light of expanding research on South American conifer invasions, the regulatory frameworks and best practices of other regions may suggest a more comprehensive and effective South American response than presently exists. Large exotic mammal effects on introduced conifer invasions: Do they promote or hinder the invasion? RELVA M.A.* (1); NUñEZ M.A. (2) and SIMBERLOFF D. (2) (1) Laboratorio Ecotono, Inibioma, Universidad Nacional del Comahue-Conicet, Quintral 1250, 8400 Bariloche, Río Negro, Argentina (2) Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA *arelva@crub.uncoma.edu.ar Exotic conifer spread is a growing concern in vast areas of the southern hemisphere since afforestation as a commercial activity is increasing, and multiple impacts on local biotas and ecosystem processes have been documented. However, it is still a challenge to understand some mechanisms driving the invasion process. It has been suggested that exotic herbivores (from insects to mammals) tend to promote invasion of exotic plants, but this could depend greatly on context. Herbivory by large exotic mammals and associated activities such as trampling, defecation and urination have been seen as having two opposite effect on conifer invasion: hindering conifer invasion or promoting it. Here, we suggest that the type (domestic vs. wild animals), intensity of herbivory, and local plant community (forest vs. non forest) can be key factors determining the type of response (facilitation or inhibition). Domestic animals seem generally to affect conifer establishment negatively, likely because of their high densities; and non-forest areas appear to be more sensitive to the presence of mammalian herbivores. Together these results, gathered from different continents, show that the response of invasive conifers to exotic herbivores is highly context-dependent but that some clear response patterns do exist. The contribution of different factors to explain Pinaceae invasion on Isla Victoria, Argentina NUñEZ M.* and SIMBERLOFF D. University of Tennessee *mnunez@utk.edu Biological invasions are a worldwide problem for the economy and for biodiversity conservation. In the relatively short history of invasion biology, several hypotheses have been proposed to explain the success or failure of introductions of exotic species, such as the enemy release, biotic resistance, and facilitation hypotheses. We tested different factors that correspond to different general hypotheses to understand the factors controlling the invasion of Pinaceae on Isla Victoria, Nahuel Huapi National Park. On this island 80 years ago more than 130 species of exotic trees were planted in large quantities and most of the plantations still remain. We analyzed the role of seed predation (corresponding to the biotic resistant hypothesis), facilitation by mycorrhizal fungi (facilitation hypothesis), deer herbivory by exotic deer (enemy release hypothesis), propagule pressure (stochastic factors hypothesis), and species traits (intrinsic invasiveness hypothesis) with field and greenhouse experiments and with field surveys. We found that intense seed predation and the lack of proper mycorrhizal fungi may be halting the invasion of exotics, while deer herbivory seems to have a positive effect on the invasion. Propagule pressure and species traits appear to play rather minor roles in these invasions. These results show that multiple hypotheses collectively help explain plant invasions and that multiple factors are involved in the success or failure of biological invasions. Wilding conifers in New Zealand – research and collaboration with affected stakeholders LEDGARD N.* Scion, PO Box 29237, Fendalton, Christchurch, New Zealand *nick.ledgard@scionresearch.com Background. The natural regeneration or spread of introduced conifers (wildings) is causing concern in New Zealand, particularly in the eastern parts of the South Island. Objectives. The project’s objectives were to improve spread risk assessment and mapping, determine the most cost effective means for controlling wilding conifers, assess vegetation successions associated with conifer management, and improve public awareness of wilding spread and its control. Methods. A South Island Wilding Conifer Management Group was established (2006) to achieve these objectives. It represented affected stakeholders, such as central and regional government departments and agencies, plantation forestry companies, conservation groups and farmers. The Group obtained funds from end-users and the Government’s Sustainable Farming Fund for a 3 year project (2006-2009). Results. The project has produced a wilding risk assessment decision support system and maps of wilding-affected areas, a wilding control handbook, reports and papers showing how different control techniques affect subsequent vegetation successions, and significant improvement in wilding awareness, particularly via an annual Newsletter and media articles, a dedicated website (www.wildingconfers.org.nz). Conclusions. A combination of those affected by conifer spread and specialist researchers, has proved to be a successful means of improving wilding risk assessment, control techniques and awareness. Ecology, management and conservation of austral cool-temperate forests: the role of long-term research sites. Integrating unperceived biodiversity into long-term socio-ecological research and conservation of austral forests ANDERSON C.B.* (1); ROZZI R. (2); MASSARDO F. (3); MANSILLA A. (3) and PIZARRO J.C. (4) (1) Programa Omora, Universidad de Magallanes & University of North Texas (2) Programa Omora UMAG, UNT & IEB (3) Programa Omora - UMAG & IEB (4) Programa Omora- UMAG & IEB *christopher.anderson@umag.cl The austral forests are known as remote, pristine and species poor, based in large part on research biased towards particular taxa (vertebrates and wood plants) and periodic studies (short, summer seasons). As a result, the area appears in few national and international conservation prioritization schemes. Such perceptions also have led to numerous government efforts to “enhance” ecosystems by introducing new, exotic species. Furthermore, the large percentage of state protected areas implies a high conservation status for the area, but many parks lack appropriate infrastructure, personnel and management plans. To overcome these challenges and to enhance the valuation of native biodiversity in research, education and conservation, the Omora Ethnobotanical Park (OEP) is developing a novel Long-Term Socio-Ecological Research (LTSER) approach that integrates the humanities and the sciences and attempts to bridge the gap between academia and society. We propose a four-step cycle to better link research discoveries and decision making by interrelating (i) ecological research, (ii) metaphorical communication, (iii) field activities guided by environmental philosophy and ecological science, and (iv) in situ conservation. Begun in 2000, this effort has conformed part of Chile’s nascent LTSER Network since 2008 (www.ieb-chile.cl/ltser) and produced such innovations in sustainable development as Tourism with a Hand Lens. Projects: CONICYT PFB-23, ICM P05-002, USNSF OISE 0854350. Long-term research in silvopastoral systems in Nothofagus antarctica native forests in southern Patagonia, Argentina PERI P.L.* (1); MARTINEZ PASTUR G. (2); MONELOS L. (3); BAHAMONDE H. (4) and LENCINAS M.V. (2) (1) INTA-UNPA-CONICET (2) CADIC (3) UNPA (4) INTA *pperi@correo.inta.gov.ar Nothofagus antarctica native forests in Patagonia that cover 751.643 ha are being used mainly for cattle grazing (70% of the total area), firewood extraction, tourism and recreation activities. Silvopastoral systems in these forests, that combine trees and grasslands or pastures under grazing (mainly sheep and cattle production) in the same unit of land, would be an economical, ecological and social productive alternative in southern Patagonia. The sustainable management of these forests has been legally declared as an objective. In this context, long-term research to account for the ecological and economic interactions (positive and/or negative) between the woody, non-woody and animal components of these systems had been established. Data on above- and below biomass, carbon and nutrient accumulation in different tree components, dry matter production and quality of pastures, wood production from thinning schedules, animal performance (stocking rates, live weight gains) and regeneration have been evaluated to determine the impact of silvopastoral system practices. However, research on sheep and cattle production at farm level over a year, the improve of primary and secondary timber industry that incorporate value to the harvested wood, and further studies that incorporate the impact on landscape and fauna connectivity at regional level, are needed. Integrated economical information and social aspects of silvopastoral systems in the region also are important to be developed. Regeneration dynamics in managed Nothofagus forests of Patagonia: Variable retention and shelterwood cuts implications MARTINEZ PASTUR G.J.* (1); LENCINAS M.V. (2); CELLINI J.M. (3); BARRERA M. (3) and PERI P.L. (4) (1) CADIC CONICET (2) CADIC - CONICET (3) LISEA - UNLP (4) INTA - UNPA - CONICET *cadicforestal@gmx.net When a new silvicultural method was proposed, foresters in Patagonia used the regeneration as the decisive indicator to evaluate it. For this, silvicultural research projects focus their studies on the regeneration dynamics, but also in remnant overstory stability, understory and soil nutrient changes, eco-physiology, micro-environments influence, micro-climate and browsing. Most of these studies were conducted in long-term research plots. The present work presents ten years results of regeneration dynamics, and their silvicultural implications of the two main regeneration treatments: shelterwood cuts (SC) and variable retention (VR). Results showed that: (1) seedlings were established after the harvesting and few of the plants of primary forests survived; (2) establishment and growth were related to canopy closure, and magnitude of micro-climate and soil properties changes; (3) remnant overstory stability were deficient in SC and dispersed retention, but was stable into the aggregated retention, influencing over establishment and growth; (4) understory and micro-environments in the harvested areas significantly influence over regeneration dynamics; (5) cattle and guanaco browsing not limited the regeneration, but influence over growth during the first years after the harvesting. Both theoretical proposals regenerated the stands, but SC homogenizes the growing conditions in the stands and VR maintained some of the original heterogeneity of the primary forests. Selective logging in rainforests of Chiloé Island: Effects on species composition and soil nitrogen transformations PéREZ C.* (1); CARMONA M. (2); FARIñA J. (1) and ARMESTO J. (1) (1) Universidad Cat¨®lica de Chile (2) Universidad de Chile *cperez@bio.puc.cl Silvicultural practices that change forest structure and composition can alter key ecosystems functions that dependent on the quality and quantity of organic matter that enters the ecosystem, such as microbial nitrogen transformations. To test this hypothesis we studied lowland rainforests in Chiloé Island, affected by industrial selective logging (ISL), traditional selective logging (TSL), and a reference uncut old growth forests (OG). In TSL dominant understory species have a significantly higher C/N ratio of litterfall than in ISL. OG forests have significantly higher rates of non-symbiotic nitrogen fixation in the Ol horizon (estimated by the acetylene reduction assay) and lower content of available nitrogen in surface soils than logged forests. Denitrification rates (estimated by the acetylene inhibition assay) tended to be higher in soils of ISL with a significantly higher NO3-N/Nt in the spring waters, which enriched δ15N signal in surface soils. We conclude that the dominance of the intolerant understory species Chusquea quila in ISL, with a lower C/N ratio of litterfall, loose the tightness of the nitrogen cycle by increasing nitrogen availability and therefore the potential of gaseous nitrogen losses and a higher proportion of nitrate in spring waters. On the contrary in TSL a higher C/N ratio in litterfall of shade tolerant understory species would decrease the chances of N losses increasing C and N storage in soil. Fondecyt 1050830, Fondap1501-0001, ICM-P05-002. Silvicultural performance of alternatives to clearfelling in wet eucalypt forests: Findings from long-term research at Warra, Tasmania, Australia NEYLAND M.* (1); BEADLE C. (2); HICKEY J. (1) and ZIEGELER D. (3) (1) Forestry Tasmania (2) CSIRO Sustainable Ecosystems (3) Private consultant *mark.neyland@forestrytas.com.au The Warra silvicultural systems trial was established in wet Eucalyptus obliqua forest to compare the traditional clearfell burn and sow (CBS) approach to harvesting and regeneration of these forests, with a range of alternative treatments. One aim of the alternative treatments was to enhance the biodiversity of the regenerating stand compared to that following CBS. The treatments were monitored for a wide range of response variables, including the vascular plant response. The floristic response in any given coupe following the harvesting and burning disturbance was related to the pre-harvesting floristics and not to the silvicultural system. Damage to the edges of retained forest areas was minimal, except for the smallest areas, which were prone to windthrow and were often burnt during the regeneration burn. Larger retained areas persisted intact throughout the harvesting and burning and for the first few years after those disturbances. In developing the range of alternatives to clearfelling that have been examined in this study, one consideration was maximisation of the area of the coupe that remained post-harvesting within one tree height of retained forest. Such areas should be colonised more rapidly by later successional species, where they occur within the retained forest, than otherwise. Future studies will be able to examine this question, but it may take some decades for the forest influence to be reflected in the standing vegetation. The role of long-term ecological research in guiding advances in silviculture: an example from Tasmania GROVE S.*; NEYLAND M. and BAKER S. Forestry Tasmania *simon.grove@forestrytas.com.au Objectives Tasmania’s Warra Long Term Ecological Research site is well-placed to support the development of native forest management approaches that better cater for biodiversity. Accordingly, it is the location for a series of long-term studies on forest ecology, biodiversity and silviculture. Methods The main study has been the Warra Silvicultural Systems Trial, which has included a replicated comparison of several alternatives to clearfelling in lowland wet eucalypt forests. Before-After-Control-Impact biodiversity studies (birds, beetles, vascular and non-vascular plants) hang off this trial. Additional studies monitor forest structural development and biodiversity along a wildfire chronosequence, and the biodiversity of decaying logs. Results While most studies are still in progress, some are now a decade old. Convergent findings from multiple research projects has demonstrated that aggregated retention can be a safe, feasible and ecologically appropriate alternative to clearfelling. Conclusions Long-term ecological research has an important role to play in guiding advances in silviculture. Because this sort of research takes a substantial commitment of time and resources, the challenge is for researchers to constantly demonstrate its relevance among management agencies, politicians and the general public. Gondwanic connections in Fungi. A Gondwanan origin for the Laccaria – Hydnangium clade (Basidiomycota, Agaricomycotina) Clade MUELLER G. (1) and HOSAKA K.* (2) (1) Chicago Botanic Garden (2) Japanese National Museum of Nature and Science *gmueller@chicagobotanic.org Objectives The Laccaria – Hydnangium clade is an appropriate model system to study diversity, biogeographic, and host specificity patterns of macrofungi. Preliminary phylogenetic hypotheses indicated that basal members of the clade occur in Australasia. Methods Multigene phylogenetic analyses were undertaken with material covering the distribution and much of the morphological range of the clade. No significant conflict was detected between data partitions so the datasets were combined. Both maximum parsimony analyses and bayesian analyses were undertaken. Results Hydnangium is nested within Laccaria. A number of previously undescribed species were uncovered. All taxa from temperate South America and Australasia, including taxa from Papua New Guinea, form a basal paraphyletic grade. Taxa from tropical America, tropical Asia, and temperate North Hemisphere form a well-supported clade nested within the austral paraphyly. All New Zealand Nothofagus-associated taxa form a monophyletic group, but they are nested within the austral. Myrtaceae-associated taxa on New Zealand are found intermixed with Australian Myrtaceae-associated taxa. Conclusions Biogeographic and diversity patterns suggest that the clade is of Gondwanan origin with a subsequent radiation to the north. While we detect a strong vicariance signal, dispersal and subsequent radiations are responsible for the current distribution patterns. Historical host specificity is not strongly supported in our phylogeny. Corticioid fungi (Aphyllophorales, Basidiomycota): Southern and North – South connections among wood-inhabiting fungi HALLENBERG N.* (1) and ANTONELLI A. (2) (1) Dept of Plant and Env. Sciences, Gothenburg (2) Institute of Systematic Botany, Zürich *nils.hallenberg@dpes.gu.se Corticioid fungi are particularly common in temperate forest ecosystems worldwide. Their life cycle is short and limited to the duration of their host, a wooden substrate. During the last decades, the corticioid flora has been increasingly updated in southern Argentina, Australia and New Zealand. Among 152 recorded species from Patagonia, 44% are also found in NZ/Australia, while 62% are reported from North America. The number of species with an exclusively austral distribution is very low. However, these figures are based on a morphological species concept, whereas molecular analyses tell a different story. Using a large sample of ITS-sequences and crossing tests, two corticioid species complexes with a worldwide distribution have been investigated. Most of the cryptic species identified have ranges extending over more than one continent, while just a few have occurrences on both hemispheres. In order to estimate the timing of transoceanic dispersals inferred from their phylogenies, we calculated absolute ages based on the molecular divergence among samples from Greenland. All diversification events separating cryptic species were estimated to have taken place in the Late Pleistocene, while virtually all diversification within cryptic species were limited to the Holocene. The drastically changing climate regimes of the Pleistocene have caused temperate forests to move between refugia and interglacial ranges, with mixing of the corticioid flora as a consequence. Do ectomycorrhizal and saprotrophic fungi show different biogeographical patterns? HOSAKA K.* National Museum of Nature and Science *khosaka@kahaku.go.jp Although fungi are ubiquitous and play an important role in terrestrial ecosystems, fungal biogeography (also known as “mycogeography”) has not been extensively studied within a phylogenetic framework. The cryptic nature of many fungi makes them difficult to sample, and thus hindering global scale biogeographical studies. In this talk, I will examine my preliminary results from multigene analyses of Hysterangiales and Geastrales, two of the four major orders within the subclass Phallomycetidae (Agaricomycetes, Basidiomycota), to understand the comparative biogeography of closely related, but morphologically and ecologically distinct groups. For example, unlike Hysterangiales, which is characterized by ectomycorrhizal habit and hypogeous (below-ground) fruiting bodies with spore dispersal by animal (i.e., rodents and small marsupials) mycophagy, Geastrales is characterized by saprobic habit and mostly above-ground fruiting bodies with spore dispersal by wind. Comparative biogeography of four closely related groups within Phallomycetidae will provide exciting insight into the fungal biogeography, which is still in a developing stage as compared to plant and animal studies. No such comprehensive biogeographical studies for macrofungi are yet available. Molecular phylogeny and evolution of the 5S gene in the root-infecting fungal genus Armillaria PILDAIN M.B. (1); RAJCHENBERG M. (1); WINGFIELD M. (2); WINGFIELD B. (2) and COETZEE M.* (2) (1) Centro de Investigación Forestal CIEFAP, CONICET (2) Forestry & Agricult Biotech. Inst., Univ. Pretoria *mbpildain@ciefap.org.ar Knowledge of phylogenetic relationships from South America (SA) Armillaria species with those of other Armillaria species is almost non-existent. In addition, previous studies have shown differences in the transcription direction of the 5S gene between species of Armillaria. The aims of this study were to characterise Armillaria isolates from Nothofagus forests in the Patagonian Andes using DNA sequences and to determine their phylogenetic relationships with other Armillaria species, and to consider the evolution of the 5S gene for a global Armillaria collection. DNA sequences from the ITS region, LSU gene and the 5S gene were used. Phylogenetic trees from the IST and LSU sequences separated the Armillaria isolates in four lineages (L). LI and LII are related with species of Australasia and showed considerable intra clade sub-structure. LIII and LIV are distinct species and are most closely related to species from New Zealand and Kenya. IGS-1, 5S gene and IGS-2 regions were sequenced to determine the the orientation of the 5S gene. Sequence analysis showed that invertion included only the 5S gene together with a few nucleotides from the IGS-2 region, and that the 5S gene is evolutionarily unstable in species originating from the Southern hemisphere (SH). This is the first comprehensive study of the phylogenetic relationships of Armillaria species from the SH including SA isolates and is one of the few where the evolution of 5S gene in fungi is analysed. Phylogeography and speciation in Patagonia: a common perspective across taxa? Climate and life history influence ancestral population dynamics of two widespread Patagonian fishes RUZZANTE D. (1); ZEMLAK T.* (1); WALDE S. (2); CUSSAC V. (3) and HABIT E. (4) (1) Dalhousie University - Canada (2) Dalhousie Unversity - Canada (3) Universidad del Comahue Argentina (4) Universidad de Concepcion - Chile *daniel.ruzzante@dal.ca This presentation will summarize progress in our understanding of how paleoclimate & paleogeography interacted with ecology & life history to effect ancestral population dynamics & phylogeographic patterns within two widespread Patagonian fish groups: Percichthyidae 7 Galaxiidae. We examined variation in mtDNA/nuclear sequences in four species collected throughout their ranges: Percichthys trucha, Percilia sp, Galaxias platei and G. maculatus. We identify glacial refugia, secondary contact zones and infer patterns of demographic expansion. Several important climate events were associated with major demographic changes in P. trucha and G. platei. This last species underwent a strong bottleneck during the LGM and exhibited four deep lineages likely representing its initial division by Andean uplift, followed by further sub-division into separate glacial refugia. The more warm-adapted P. trucha showed continuous growth through the last two glacial cycles, but went through an important bottleneck ca. 180 ka. The demographic timelines obtained for the two species illustrate the continent-wide response of aquatic life in Patagonia to climate change during the Quaternary, but also show how differing ecological traits and distributions led to distinctive responses. Molecular evidence also reveals instances of drainage reversals (Atlantic-> Pacific) in G. platei and G. maculatus. G. maculatus, a diadromous species, extended its range into Argentina via the southern coastal regions. Comparing phylogeographic patterns in two species of freshwater crabs (Aeglidae) across the Andes in Patagonia CRANDALL K.* Brigham Young University *keith.crandall@byu.edu Quaternary glacial cycles have played an important role in shaping the biodiversity in temperate regions. This is well documented in Northern Hemisphere, but much less understood for Southern Hemisphere. We used mitochondrial DNA and nuclear elongation factor 1α intron sequences to examine the Pleistocene glacial impacts on the phylogeographical patterns of two species of freshwater crab, Aegla alacalufi from the Chilean Patagonia and Aegla neuquensis from the Argentine Patagonia. Phylogenetic analyses showed contrasting patterns of diversity and impact east and west of the Andes for these two species. Aegla alacalufi divergence patterns appear to be determined in large part by glacial cycles whereas Aegla neuquensis diversity and subdivision falls along river drainage divides (biogeographic influences). The relative timing of divergences was also determined to be quite different between these two species. Multiple periglacial refugia and post-glacial colonization of the Andes in the Patagonian herb Calceolaria polyrhiza COSACOV A. (1); SERSIC A.N.* (1); SOSA V. (2); JOHNSON L.A. (3) and COCUCCI A.A. (1) (1) IMBIV - CONICET - UNCordoba (2) Instituto de Ecología - Xalapa - Mexico (3) BYU - Provo - USA *asersic@com.uncor.edu For Calceolaria polyrhiza we aimed to determine whether phylogeographic patterns corresponded to in situ Pleistocene survival or to glacial retreat and postglacial expansion and, to reveal putative glacial refugia and post-glacial colonization routes. Haplotypes (27) of the trnH-psbA- intergenic cpDNA spacer were obtained from 68 populations (590 indiv.) covering the entire range of this widely distributed Patagonian endemic herb occurring both in the temperate forests and arid steppe. Three phylogeographic breaks revealed four major lineages: two high Andean split first during the late Miocene, and two Patagonian, ca 4 Ma BP coincident with the steppe establishment. The Patagonian groups exhibited diversification, rapid population expansion and colonization of the Andes flanks to the end of the Pleistocene. Populations in formerly ice-covered locations are monomorphic for the four most abundant haplotypes, suggesting recent independent colonizations by zonal steppe lineages. Highest diversity spots were found along a N-S transect congruent with the GPG ice-sheet limits. Past climate fluctuations influenced on diversification, distribution and demography of this plant. A scenario of multiple periglacial Pleistocene refugia and subsequent multiple recolonization routes, from east Patagonia to the Andean flanks, is proposed. The phylogeographic structure also preserves imprints of older phenomena, suggesting multiple and complex processes may moulded biodiversity in Patagnia. P aleogeographic evolution of patagonia and its continental shelf fromhe Last Glacial Maximum to the early Holocene PONCE J.; RABASSA J.* and CORONATO A. CADIC-CONICET *jrabassa@gmail.com We developed a model of sea level change to describe the paleogeographic evolution of Patagonia and its continental shelf from the Last Glacial Maximum (LGM, ca. 24 cal. ka BP) to the early Holocene. Sea level during the LGM was 120-140 m below present level leaving a vast area (ca. 0.6 million km2) of the current continental shelf exposed. The emerged area during the LGM varied in width from ca. 500 km to 100 km at the latitudes of Bahía Blanca and Tierra del Fuego, respectively. The Malvinas archipelago comprised a single large island (46,000 km2), four times larger than the currently exposed area. It was separated from the continent by a straight 220 km long. Another island (ca. 13,600 km2) likely existed in the area currently known as Burkwood Bank, south of Malvinas from the beginning of MIS 2 (ca. 30-40 ka BP) to ca. 15.5 cal. ka BP. The exposed area of the current continental shelf is likely to have been halved around 15.3 cal. ka BP when sea level was ca. 90 m below present level. The current coastline was likely in place between 11 and 9 cal. ka BP. The straight of Magellan is likely to have been formed ca. 10.2 cal. ka BP when sea level rose to ca -35 m. Our model facilitates paleoenvironmental and paleoclimatic reconstructions that may help understand faunal/floral dispersal throughout the region during the Late Glacial period and early Holocene. Our method could also be useful for the reconstruction of the paleogeography of earlier glacial-interglacial transitions. Patterns of genetic diversity and the history of sigmodontine rodents in Patagonia and Tierra del Fuego LESSA E.P.* (1); D'ELíA G. (2) and PARDIñAS U.F.J. (3) (1) Universidad de la República, Uruguay (2) Universidad de Concepción, Chile (3) Centro Nacional Patagónico, Argentina *enrique.lessa@gmail.com Species are impacted by climate change at different time scales. Studies in northern continents have documented dramatic shifts in distributions of species subsequent to the Last Glacial Maximum, particularly at high latitudes. However, little is known about the history of southern continents, especially at high latitudes. South America is the only continental, other than Antarctica, that extends significantly into latitudes higher than 40 °S. Genetic studies of a few Patagonian species have provided seemingly conflicting results, indicating either postglacial colonization from restricted glacial refugia or persistency through glacial cycles and in situ differentiation. Using mitochondrial DNA sequences of 14 species of sigmodontine rodents, a major faunal ensemble of Patagonia and Tierra del Fuego, we show that at least 9 of these species bear genetic footprints of demographic expansion from single restricted sources, although timing of demographic expansion precedes the Last Glacial Maximum in most, whereas four are fragmented phylogeographically. Our results indicate that a) demographic instability in response to historical climate change has been widespread in the Patagonian-Fueguian region, and is generally more pronounced at high latitudes in both southern and northern continents; b) colonization from lower latitudes is an important component of current Patagonian-Fueguian diversity; but c) in situ differentiation has also contributed to species diversity. Temporal congruence of replicated patterns of vicariance and range expansion in Patagonian lizards MORANDO M.* (1); CAMARGO A. (2); AVILA L.J. (1) and SITES J.W.,.J. (2) (1) CENPAT (2) Brigham Young University, USA *morando@cenpat.edu.ar Based on cytochrome-b data, there are replicated patterns in different clades of Patagonian lizards. Closely related haploclades are distributed North and South of the Somuncurá Plateau, suggesting a common vicariant event. We did comparative analyses in 5 lineages to test for temporal congruence based on the following taxa and sample sizes: L. bibronii (N=50, S=50), H. darwinii (N=25, S=25), L. bellii (N=6, S=9), L. melanops (N=50, S=50), L. petrophilus (N=30, S=30). For three of these we tested for a simultaneous southern expansion: L. bibronii (N=46, S=50), L. fitzingerii (N=44 S=42), H. darwinii (N=23, S=37). We used MrBayes to estimate parameters for different models with 1 million simulations for each. For both patterns there is a strong signal for a single event that affected all lineages and occurred very recently (mean time ~6,000 y.a.) and probably simultaneously, or the southern expansion shortly after the N-S Somuncurá divergence. After the last glacial maximum, mean temperature increased rapidly and considerably and sea level rises covered the same amount of land now above sea level, likely pushing easternmost populations towards the west and south. As these populations encountered the Somuncurá Plateau, they split into northern and southern clades, and a third wave of migration further south into land previously covered by permafrost. In these lineages there is higher genetic diversity the east coast, supporting the idea of eastern refugia during glacial times. Towards a southern synthesis of urban environments: catching up with the north and points of difference. A synthesis of southern hemisphere urban biotopes: effects of colonial settlement and recent globalization STEWART G.*; IGNATIEVA M. and MEURK C. New Zealand *stewartg@lincoln.ac.nz In our presentation we compare and analyse the historical development of urban cities and towns in the southern hemisphere, their existing planning structures, architecture and urban biotopes. There are striking similarities in urban biodiversity development and also trends in protecting and reinforcing nature in cities and towns in temperate regions of the southern hemisphere. Most urban biotopes in southern hemisphere cities also reflect broader tendencies towards globalisation and unification. However, regional differences are maintained at least in the subtext of universal biotopes. We present a synthesis of southern hemisphere biotopes with an emphasis on those in New Zealand but also draw on more global comparisons using urban lawns as an example. We illustrate the globalised (N hemisphere) component in lawns but also highlight the unique, intertwining, indigenous components separately. Lawns are a product of the 18th and 19th century Picturesque landscape movement and are now used as a key feature in urban open spaces from public parks to private gardens. In times of climate change and increasing awareness of urban sustainability, lawns might be viewed as ecologically extravagant elements that require herbicides, fertilisers and irrigation and contribute to urban pollution and loss of biodiversity. There is a movement in the USA, UK, Australia and New Zealand to find alternative solutions such as edible lawns, meadows and biodiverse lawns. Changes in natural vegetation preserved in cities, highlighting similarities and differences between southern and northern cities FLORGåRD C.* Swedish University of Agricultural Sciences *clas.florgard@sol.slu.se The concept of preservation of indigenous vegetation within cities comprises utilization of the existing natural vegetation in areas where buildings and infrastructure are to be developed. The objective of the presented project is to create a knowledge base for preservation. Since 1972 a research project is running in a suburban residential area in Stockholm, Sweden. Natural vegetation preserved within the residential area and in an undeveloped reference area were surveyed from the time before construction begun through 34 years of residential use. The vegetation development was studied using time-lag and CSR (Competitors-Stress tolerators-Ruderals) analyses. Annual species turnover in the built-up area was higher than in the reference area but the longterm rate of change was equal. The CSR direction of the change differed between the two areas in that the composition of the vegetation in the residential area moved towards ruderality (R). The magnitude of the change in CSR space was however equal. Results show that urban use, mainly trampling, affects plant composition gradually. The deterioration was slow but after 34 years still progressing. In areas in the southern hemisphere it is likely that other vegetation reactions may occur. Concerning the possibilities to control impact on the vegetation as well as vegetation changes it is likely that the possibilities in the Northern countries as well as the Southern countries are the same. Evaluation of urban nature reserves - Buenos Aires as a case study. BREUSTE J. (1) and FAGGI A.* (2) (1) Centre for Landscape Research (CeLaRe), Germany (2) Universidad de Flores, Buenos Aires, Argentina *juergen.breuste@sbg.ac.at Objectives: This study investigates opinions and attitudes of visitors and neighbors of 5 urban reserves located in the Buenos Aires metropolitan area for further urban nature management. Methods: The selected nature reserves have similar physiographic characteristic but with differences in some environmental and socioeconomic features. 600 people were interviewed gathered data about utilization and evaluation of the reserves, distance travelled and effort required to reach the place, perception of nature, their flora and fauna knowledge, and features from a landscape they preferred. Results: Effort required to reach the reserves varied between 20 minutes and 1 hour; the duration of the visit between 20 minutes and more than 4 hours. Visitors showed few flora (76%) and fauna (80%) knowledge, although they pointed out “nature” as the principal feature they preferred from a landscape. Many interviewed agreed in the necessity to improve infrastructure and information on nature. Results showed that profile, gender, age and education level were the main explaining variables. Conclusions: Similarities and differences between the visitors and neighbors perception are being discussed. Comparisons with results from European studies show general similarities in behavior but also differences in nature perception. This necessity is coincident with the lack of biodiversity knowledge, a fact that is controversial with the mission of urban reserves. Urban domestic gardens in developing countries: biodiversity conservation and/or poverty alleviation? CILLIERS S.S.*; SIEBERT S.J. and DAVOREN E. School of Environmental Sciences and Development, North-West University, Private Bag x6001, Potchefstroom, 2520, South Africa *sarel.ciliers@nwu.ac.za Increasing urbanization causes environmental changes such as transformation, fragmentation, alteration of species composition and depletion of ecosystem services. Human socio-economic aspects, in terms of health and well-being, are also influenced. The complex socio-ecological nature of urban ecosystems requires an integrated approach in urban ecological studies. The entire urban green infrastructure, including private gardens should be studied. Gardens appear to be too small to be of biological significance, but their total area is too large to be ignored. The first objective of this presentation is to compare the different approaches in domestic garden research in the northern and southern hemispheres. In developing countries, the emphasis is more on urban agriculture, agroforestry and socio-economic and cultural values, than in developed countries. The second objective is to describe and compare plant diversity of gardens in urban South Africa in terms of patterns and drivers. Spatial statistics and ordinations have shown different patterns of gamma, alpha and beta diversity in the different settled areas. The final objective of this presentation is to explore the application of ecological studies in gardens in the northern and southern hemispheres in planning, design and management of urban areas, based on a landscape ecological approach. Important aspects include the issue of scale and the concept of ecological land-use complementation. Vegetation classification of the urban forest: How to begin ZIPPERER W.C.* USDA Forest Service, P.O. Box 110806, Gainesville, FL 32611 *wzipperer@fs.fed.us During the past century, the world has seen unprecedented land-use change because of rapid growth of the human population. The conservation of existing plant assemblages has necessitated their documentation and classification in consistent and standardize typology. Recent classification systems developed for the United States (U.S.)—the National Vegetation Classification, and for Europe—European Vegetation Survey have not been applied to urban landscapes. Yet, the conservation of plant assemblages in urban landscapes is paramount because of the benefits human derive from those systems. To be successful, we first must decide what is going to be inventoried—patches of remnant communities, patches of emergent communities, and/or patches of cultural communities where culture is defined by land use (e.g., residential, commercial, institutional, and transportation). Second, we need to develop a standardized inventory system for comparability across urban landscapes. In addition, the system must correspond to existing inventorying protocols used to document natural vegetation in adjacent rural landscapes. Finally, we need to link the classification to alliances and associations identified regionally. I will use examples from the U.S. and New Zealand to illustrate these points. Origin and diversification of the New Caledonian biota. Biogeographic history of New Caledonian diving beetles based on molecular phylogenies BALKE M.* (1); HENDRICH L. (1); PONS J. (2); VOGLER A. (3) and RIBERA I. (4) (1) Zoological State Collection (2) Institut Mediterrani d'Estudis Avançats (CSIC-UIB) (3) Natural History Museum (4) 2Institute of Evolutionary Biology (CSIC-UPF) *michael_balke@yahoo.de We focus on a molecular phylogenetic analysis of Exocelina diving beetles. We find a basal position of Australian species in a paraphyletic series, with more recent nested radiations in New Caledonia and New Guinea. Our analyses suggest that dispersal played an important role in the formation of these large insular faunas, although successful colonization appears to be a rare event, and, in this case, is unidirectional. Whether or not a lineage is present on an island is due to chance: Exocelina are absent from Fiji, where related Copelatus have radiated extensively in the same habitats occupied by Exocelina in New Caledonia and New Guinea, while Copelatus are absent from New Caledonia with the exception of a widespread lowland pond species. Lineages of Exocelina apparently colonized New Caledonia twice, and both lineages are derived from an Australian ancestor. The older clade is represented only by two apparently relictual mountain species (one morphologically strongly adapted to highly ephemeral habitats), while the younger clade contains at least 20 species exhibiting great morphological diversity. More generally, we will present a mitochondrial DNA landscape of a near complete species-level sampling of Australasian diving beetles to better understand the biogeography of New Caledonia. We show that in stagnant water species colonization was either recent or occurs repeatedly and recently, as populations from all over Australasia lack stronger geographic signature. Biogeography of Citrus and other aurantioid Rutaceae PFEIL B.* (1) and CRISP M. (2) (1) University of Gothenburg (2) Australian National University *bernard.pfeil@dpes.gu.se The geological history of Australasia, New Caledonia, and Southeast Asia, has been complex, resulting in competing biogeographic hypotheses for taxa found here. Alternative hypotheses – Gondwanan vicariance, rafting terranes, long-distance dispersal – may be distinguished by different predicted divergence times between disjunct sister taxa. The plant family Rutaceae, in particular subfamily Aurantioideae, can be used to test these hypotheses for these taxa because of their distributions. Therefore, the ages of Rutaceae and subfamily Aurantioideae were estimated using molecular dating. One data set comprised 51 sequences of rbcL and atpB with sampling across rosids and three fossil calibrations: crown Fabales+Fagales+Rosales ( > 94 Ma), Fabaceae ( > 51 Ma) and stem Ailanthus , Simaroubaceae ( > 52 Ma). Another data set comprised 81 Aurantioideae using > 8 kb of chloroplast sequence and secondary calibration. Confidence in estimated divergence times was explored by varying the root age, dating method (strict, local, and relaxed clocks), and inclusion of internal calibrations. We conclude that the Rutaceae crown diverged in the Eocene (36.4 – 56.8 Ma, mean 47.6), whereas the Aurantioideae crown originated in the early Miocene (12.1 – 28.2 Ma, mean 19.8). This young age suggests that Gondwanan vicariance does not explain the distributions of extant Aurantioideae. Taxa found in New Caledonia may have instead arrived by separate transoceanic dispersal events. Can panbiogeography provide credible scenarios for the origin of the New Caledonian biota? A case study of Sapotaceae SWENSON U.* (1); ALEXANDRE A. (2); JéRôME M. (3); MATTIAS M. (1) and PORTER P. L.I. (4) (1) Swedish Museum of Natural History (2) Institute of Systematic Botany, Zürich (3) Laboratoire de Botanique, Noumea (4) Missouri Botanical Garden *ulf.swenson@nrm.se Recent panbiogeographic ideas suggest that the biota of New Caledonia was inherited from the amalgamation of several geological terranes, the latest in the Eocene. Evidence is supposedly derived from the fact that many plant and animal taxa are strictly confined to non-ultramafic, ultramafic, or calcareous substrates. However, these taxa ought to form clades in accordance with substrate. Also, panbiogeography suggests that species found on isolated (largely ultramafic) mountains along the west coast and in the south exhibit a disjunct distribution due to lateral movements of the West Caledonian fault. To test these ideas, we present a well-sampled Bayesian phylogeny based on four molecular markers and a dating analysis of Pycnandra (Sapotaceae). Our conclusive results show that the ancestor of Pycnandra is approximately as old as the emplacement of the New Caledonian ultramafic nappe (~ 36 Ma). In addition, colonization of the area is estimated to have taken place between 36.0 and 30.1 Ma, congruent with a single long-distance dispersal and subsequent species radiation, but incongruent with panbiogeography. Soil specificity is labile in the phylogeny, indicating that multiple independent adaptations to various non-ultramafic soils. Disjunctions among taxa in New Caledonia may be explained equally well by long-term erosion of the ultramafic nappe, yielding the observed old ages of species with population-level disjunctions, or by short-distance dispersal events. Multiple lineages of Apiales in New Caledonia: colonization, diversification, and dispersal across seven clades LOWRY P.* (1) and PLUNKETT G. (2) (1) Missouri Botanical Garden (2) New York Botanical Garden *Pete.Lowry@mobot.org The flora of New Caledonia is often seen as a Gondwanan remnant, its elements derived from lineages that survived as it separated from Australia and drifted eastward (ca. 65 mya) but were largely lost elsewhere due to climatic shifts. Recent studies have challenged this, citing geological evidence that New Caledonia was entirely submerged in the Eocene, concluding that its flora must be derived from more recent colonization by long-distance dispersal. Understanding the historical origins and the processes driving diversification in this rich flora is a priority, but New Caledonia’s role as a source area for other SW Pacific floras has been overlooked. Results from phylogenetic work show that the order Apiales is represented on New Caledonia by 7 lineages (ca. 90 species, only 2 not endemic), all derived from Australasian ancestors, each of which has diversified (sometimes extensively) on the island. In 4 of these 7 groups, at least 15 dispersal events from New Caledonia have led to the establishment of lineages on nearby, mostly volcanic islands, including at least 5 colonizations to Vanuatu (followed by dispersal on to the N and to Fiji), 2 to the Solomons (and then to Vanuatu/ Fiji and to New Guinea), and 1 each to Fiji, Lord Howe and Norfolk, plus at least 1 colonization from New Caledonia to Australia. Broad regional sampling in other SW Pacific groups will likely show a similar pattern, adding an important new element to the biogeographic significance of New Caledonia. Origin and radiation of the freshwater insects Trichoptera on New Caledonian JOHANSON K.A.* Swedish Museum of Natural History, Box 50007, 104 05 Stockholm, Sweden *kjell.arne.johanson@nrm.se Trichoptera form a moderately large order of holometabolous insects, which with 14,000 described species represent the largest insect order having fully aquatic juvenile life stages. From New Caledonian (NC) Grande Terre, 19 species were recorded by end of the 1990s. Subsequent sampling revealed that the diversity comprises more than 500 species (all except two species endemic), and is divided into 24 genera in ten families. The species number matches that of Australia, and is twice as large as that of New Zealand. Our research aims at explaining causes of the extremely high species diversity on the island, taking into consideration phylogenetic relationships among the species, abiotic factors, particularly ultrabasic/non-ultrabasic substrates, as well as spatiotemporal factors. We analyzed unrelated monophyletic groups and demonstrated that the larvae of the most ancestral NC Hydrobiosidae ( Xanthochorema) and Hydropsychidae species were adapted to living on ultrabasic substrate; and that the early radiation within groups took place exclusively on that substrate, followed by late dispersals into non-ultrabasic substrate. Our molecular dating analyses show that 1) NC Hydropsychidae started radiating ca. 28 Ma, some 10 my after uplift, indicating a dispersal origin; 2) The major radiations took place 16-4 Ma; 3) Environmental diversity (altitude, precipitation, substrate types) predated, and potentially influenced on the species diversification of Hydropsychidae. Origin of the Flora of New Caledonia, past and present knowledge MUNZINGER J.* Laboratoire de Botanique et d'Ecologie Appliquées, Herbarium Nou, New Caledonia *jerome.munzinger@noumea.ird.nc New Caledonia has traditionally been considered as a piece of Gondwana that separated from Australia 65 Myr ago, and due to stable climatic conditions, it has maintained a archaic flora until today. Old and primitive lineages such as Amborellaceae, Trimeniaceae, Araucaria and Nothofagus are considered as evidence of a long stand isolation and of Gondwana origin. But recent geological findings indicate that New Caledonia was deeply submerged during 20 Myr, from times in the Cretaceous to the late Eocene (and possibly Middle Eocene), which conflicts with the idea of a long-preserved archaic island. Cumulative phylogenetics studies identify more and more groups in New Caledonia that are 35 Myr or younger, often with Australia as a source area. In all these studies, rapid speciation is observed, and sometimes, like in Cunoniaceae, speciation involves hybridization. These processes, together with adaptations to ultramafic and non-ultramafic soil conditions, would explain the high level of floristic diversity seen today on New Caledonia. The age of the New Caledonian biota: A review of the molecular evidence CARTER R.* (1); DUUS A. (1); THORNHILL A. (1); PFEIL B. (2) and CRISP M. (1) (1) Australian National University (2) University of Gothenburg *richard.carter@anu.edu.au Remote islands make for excellent testing grounds of biogeographic hypotheses. The use of molecular data for estimating divergence times between taxa is an increasing popular and sophisticated tool for exploring these hypotheses. Few islands have received more attention recently than New Caledonia and this profusion of interest has seen a great many molecular studies published. Many of these studies have used molecular dating, however, these studies have varied in their approach and methods, making direct comparison between the studies difficult. Interest in the origin of the New Caledonian biota can be divided into two overarching questions: what is the age of the biota and what is its origin? Discussion of these questions can be summarised into a general hypothesis, this being that the biota are a fragment of a formerly continuous eastern Gondwanan system, or that they arrived via some form of recent dispersal. Comparisons of multiple groups analysed in a consistent fashion could reveal the underlying patterns of their history. This study undertook a survey of the available molecular data to determine what data are available to test this hypothesis, and used that information to reconstruct dated phylogenies for a number of groups that span the diversity of the New Caledonian biota. The curious relationship of New Caledonia and Tropical Gondwana: insights from opiliofauna (Arachnida: Opiliones) SHARMA P.* and GIRIBET G. Harvard University *psharma@fas.harvard.edu The species richness and endemism of New Caledonia, traditionally held to result from Gondwanan origins and extended isolation, are increasingly attributed to recent diversification subsequent to transoceanic dispersal. In the present study, the phylogeny of the endemic harvestman family Troglosironidae (Opiliones: Cyphophthalmi) was investigated using a multilocus DNA sequence dataset (two nuclear ribosomal genes, two nuclear coding genes, and two mitochondrial genes). Timing of origin and diversification was estimated using fossil taxa for calibration in conjunction with a penalized likelihood algorithm. Phylogenetic analyses strongly support the monophyly of Troglosironidae and its sister relationship to Tropical Gondwanan Neogoveidae. Molecular dating supports a scenario of a Jurassic (~180 Ma) origin of troglosironids, with subsequent diversification of the crown group prior to the Oligocene (~47 Ma). These estimates of divergence times, in tandem with the limited distribution of Troglosironidae, suggest that this lineage constitutes an ancient relict. The relationships of the three other harvestman families endemic to New Caledonia are examined in comparison to Troglosironidae, corroborating the inclusion of both relictual taxa and long-range dispersers among New Caledonia’s arachnid fauna, and further highlighting the complex nature of the island’s biota. The origin of biodiversity in New Caledonia : past, present and future (mis)conceptions GRANDCOLAS P.* (1); NATTIER R. (1); ROBILLARD T. (1); JOURDAN H. (2); DESUTTER-GRANDCOLAS L. (1); GUILBERT E. (1) and DEHARVENG L. (1) (1) UMR 7205 CNRS, Département Systématique et Evolution, Muséum national d'Histoire naturelle, 45 rue Buffon, 75005 Paris, France (2) Centre de Biologie et de Gestion des Populations, INRA, and Laboratoire de Zoologie Appliquée, IRD, 98948 Nouméa, Nouvelle-Calédonie *pg@mnhn.fr New Caledonia is a megadiverse island characterized as a hot spot of biodiversity. It has recently attracted more attention from the scientific community with evolutionary, ecological and conservational studies developing after a long period of inventorying. These recent studies do not necessarily use updated evolutionary or biogeographical paradigms for New Caledonia. Old or misleading paradigms are still used or partly used and the relevant biogeographical tests cannot always be performed. A rebuttal is presented to the most frequent misconceptions: New Caledonia considered as a Gondwanan refuge and a Museum of Biodiversity, endemics of high taxonomic levels and relict taxa used as indicators of this refuge, geological background interpreted in ignorance of tectonics, the “island arc metapopulation” model used for perpetuating an exclusive hypothesis of Gondwanan vicariance, and finally considering metalliferous soils and landscape complexity as the main or only speciation engine. In avoidance of these misconceptions, some future research directions are outlined which could permit to understand better the origin and the characteristics of the biodiversity. 'Species' and speciation in the Southern Hemisphere: integrative approaches to studying plant species diversification. Monsoon savannas and rain forests: Diversification of the Australasian Sterculioideae CARTER R.* (1); COOK L. (2); PFEIL B. (3) and CRISP M. (1) (1) Australian National University (2) University of Queensland (3) University of Gothenburg *richard.carter@anu.edu.au The Brachychiton clade of the Sterculioideae is comprised of four genera that have speciated in the monsoon tropics and rainforests of Australasia. The three species rich genera, Acropogon, Argyrodendron and Brachychiton are largely allopatric and have contrasting patterns of species diversity. Brachychiton (with 35 species) primarily radiated across the monsoon tropics of Australia but has species that extend into all biomes of Australia. Its sister genus, Argyrodendron, with approximately half the number of species, is entirely contained in the aseasonal wet biome of Australia and Papua New Guinea. Acropogon , endemic to New Caledonia, has radiated throughout the island group with a species diversity between that of Brachychiton and Argyrodendron. Comparisons made across of a molecular phylogeny of these genera allows inferences to be made regarding the rate and mode of speciation. Furthermore, the ranges of these genera allows for exploration of the effect of biome history on species diversification. For instance, the aseasonal-wet biome of Argyrodendron is older and more stable than the monsoon biome in which Brachychiton is distributed. In this presentation results from phylogenies reconstructed from chloroplast and nuclear data for Brachychiton and Argyrodendron are shown. From these we found evidence that suggests either a rapid expansion or significant extinction in Brachychiton, whereas Argyrodendron has had a more stable speciation rate. Phylogenetic diversity in high Andean flora: taxonomic level and relationship with taxon richness for conservation SCHERSON R.* (1); NAULIN P. (1); VIDAL P. (2); HAGEMANN T. (2); RETAMALES H. (3) and KALIN ARROYO M.T. (4) (1) Instituto de Ecología y Biodiversidad, Universidad de Chile y Facultad de Ciencias Forestales, Universidad de Chile (2) Instituto de Ecología y Biodiversidad, Universidad de Chile (3) Facultad de Ciencias Forestales, Universidad de Chile. (4) Instituto de Ecología y Biodiversidad, Facultad de Ciencias, Universidad de Chile. *rscherson@uchile.cl Measures of Phylogenetic Diversity (PD) have been increasingly used in conservation to assess the evolutionary history of a biotas, and consider the amount of evolutionary history that groups of taxa represent for a certain area. We determined PD at the generic and species level and the relationship between PD and taxon richness for the Fabaceae in high elevation habitats in the Andes of South America: Páramo, Puna, and Southern Andean Steppe. Based on an available supertrees complemented with newly obtained sequences, we constructed phylogenies based on one species per genus representing the generic level, and using the average branch length or node age for two species per genus multiplied by the number of species/genus to approximate the species level. PD was measured in millions of years and as the sum of raw branch lengths. We compared PD-g (genera) with PD-s (species), and studied whether generic and species richness predicted PD-g and PD-s respectively, for each area. In Fabaceae, the proportion of total PD per sector varied with taxonomic level and with the use of ages versus branch lengths. Proportional PD-g bore a closer relationship to generic richness than proportional PD-s did to species richness. Additional analyses are being carried out for other representative families of the flora of the high Andes. Funding: FONDECYT 3085004, PDF-23, ICM P02-005. Polyploidy and breeding system changes as drivers of speciation TATE J.* Massey University *j.tate@massey.ac.nz Polyploidy (whole genome duplication) is known to be a major force that has the potential to generate new species. Concomitant changes in the breeding system of newly formed polyploids may aid in their establishment as new species. These changes in breeding strategy may involve a switch from primarily outcrossing to primarily selfing or to more extreme forms of outcrossing (e.g., from hermaphroditism to gender dimorphism). Here, I present examples of these contrasting modes of breeding system evolution in two groups of mallows (Malvaceae) with different degrees of polyploidy: Tarasa from Andean South America and Plagianthus from New Zealand. Using molecular phylogenies, the origins of polyploidy and the evolution of breeding systems were inferred. In Tarasa, multiple origins of the annual polyploid species were inferred with subsequent shifts to autogamy. The two New Zealand Plagianthus species, both of which are dioecious shrubs or trees, appear to be ancient polyploids; the origins of gender dimorphism in this lineage is equivocal. The differing factors that have contributed to species diversification in these genera will be discussed, as will the implications for larger scale patterns in these distinct biogeographic realms. Population divergence and speciation in Hypochaeris (Asteraceae, Cichorieae) from South America TREMETSBERGER K.* (1); LóPEZ P. (2); STUESSY T.F. (2); URTUBEY E. (3) and BAEZA C.M. (4) (1) University of Natural Resources and Applied Life Sciences, Vienna, Austria (2) University of Vienna, Austria (3) Instituto de Botánica Darwinion, Argentina (4) Universidad de Concepción, Chile *karin.tremetsberger@boku.ac.at The c. 40 morphologically diverse South American species of the perennial herb Hypochaeris have diversified in the Pleistocene. They have colonized large portions of the continent and grow in a diverse array of habitats. AFLP analysis has revealed phyletic assemblages within the South American radiation. The species contained in the same phyletic assemblage also occur in the same biogeographic provinces of South America. We are interested in the potentially important factors that have driven recent speciation within biogeographic regions, including divergent ecological preferences of the species (niche differentiation), changes in the reproductive system, and karyotypic changes. Ecological adaptation is suggested as a driver of speciation in the young phyletic assemblage containing H. apargioides, H. gayana, and H. spathulata. The species show parapatric distributions and divergent ecological preferences in Chile and Argentina suggestive of adaptive radiation. Self-compatibility evolved from self-incompatibility within several phyletic assemblages suggesting that inbreeding could have promoted speciation. Autopolyploidization is seen at the infraspecific level in several species. In H. incana from the Patagonian and Subantarctic region, the tetraploids show different ecological preferences than their diploid progenitors suggesting that autopolyploidization could be the starting point for a new round of diversification. Speciation and phylogeography of Telopea and Lomatia (Proteaceae) BAUM M.* (1); CRISP M. (1); ROSSETTO M. (2) and WESTON P. (2) (1) Australian National University (2) National Herbarium of NSW - Botanic Gardens Trust *melita.baum@anu.edu.au One of the main aims of evolutionary biology is to understand processes involved in speciation. Phylogeographic research aims to address these questions, by revealing the factors that have influenced evolution and distribution of species. We can determine reproductive barriers, whether they arose in allopatry or sympatry, how they may have triggered speciation and how they are maintained. Lomatia and Telopea (Proteaceae) are sister groups that, within Australia, display almost identical overall distributions, but different geographic patterns, making them ideal for exploring speciation processes. The overlap in distribution suggests that if historical events, such as climate change, have led to allopatric speciation, this should have resulted in congruent geographic patterns in both genera. A comparative phylogeography of Telopea and Australian Lomatia can test whether major geographic and environmental disjunctions correspond with genetic disjunctions. We will test for these correlations using variable DNA regions including chloroplast microsatellites and both chloroplast and nuclear sequencing. Differences and similarities of genetic structure across and within genera will be investigated, to reveal the major contributors to distribution and gene flow. Discovering whether allopatric or sympatric processes are dominant within Lomatia and Telopea will assist in determining what historical events have been important for the speciation of eastern Australian flora. Raising Zealandia: biogeography of a sunken continent. Biogeography with a sinking feeling: A geological history of Zealandia TREWICK S.* (1); CAMPBELL H. (2); LANDIS C. (3); HERZER R. (2) and PATERSON A. (4) (1) Massey University (2) GNS Science (3) University of Otago (4) Lincoln University *s.trewick@massey.ac.nz In crustal terms, New Zealand and New Caledonia are continental islands, the biggest remnants of a much larger tract of continental crust. They are emergent parts of a largely submerged eighth continent, Zealandia, which rifted from eastern Gondwanaland with formation of the Tasman Sea at c.83 Ma. About 93% of Zealandia is under the sea. Many islands of Zealandia are geologically young, and examination of mainland NZ and nearby Chatham Islands shows that geological evidence for continual presence of land since is inconclusive. A reasonably compelling geological argument can be made for maximum submergence c.23 Ma and acknowledges the possibility of total submergence. The land surface of New Caledonia is also younger than Zealandia, having undergone submarine obduction c.35 Ma. The slow sinking of a continent over a period of c. 60 million years (during Late Cretaceous to Miocene time; 83-23 Ma) is significant, and presents problems for biogeography of the region. It is possible that the modern day native terrestrial biota of NZ is entirely the product of long distance and is less than 23 million years old, and that that of NC is only about 10 million years older. How do we explain so-called relict lineages and how to we deal with phylogenetic dating if we have no certainly about landscape age? Viewed from the perspective of a sinking continent, many biogeographic inferences are unstable. Molecular phylogenetic data show that the New Zealand biota is not archaic WALLIS G.* Univ of Otago *g.wallis@otago.ac.nz The origins of the NZ flora and fauna have long been debated. There has been a large accumulation of molecular phylogenetic studies over the last decade or so, making a review of this question timely. Very few taxa are even plausibly archaic. Marine species, diadromous fishes and birds dominate examples of ongoing gene flow and Pleistocene linkages. In contrast, terrestrial animals and trees dominate the few potential archaic examples. Wind or water dispersed plants commonly show close overseas relationships. These results must be seen on a background of an incomplete phylogenetic record. With respect to source landmass, extinction of lineages, or incomplete sampling (i.e. failure to include sister group), will tend to lead to an overestimate in timing. If vicariance is our null hypothesis, this overestimation can lead to Type II error. Extinction or incomplete sampling of NZ lineages, in contrast, is irrelevant, once recent links to overseas forms are demonstrated. Vicariance may be a preferable hypothesis because it is falsifiable, but falsified it has been, many times. Barring some major global realignment in calibration of molecular clocks, it now appears that NZ has few or no endemic archaic lineages at all. This finding is consistent with the near or complete submergence of Zealandia during the Oligocene, and a history of volcanism, glaciation and rather small land area over the last several million years. Relict taxa in biogeography: what do they actually tell us? GRANDCOLAS P.* (1); NATTIER R. (1); MARCHAL L. (1); JOURDAN H. (2); KEITH P. (4); PELLENS R. (1); ROBILLARD T. (1); GUILBERT E. (1) and TREWICK S. (3) (1) UMR 7205 CNRS, Département Systématique et Evolution, Muséum national d'Histoire naturelle, 45 rue Buffon, 75005 Paris, France (2) Centre de Biologie et de Gestion des Populations, INRA, and Laboratoire de Zoologie Appliquée, IRD, 98948 Nouméa, Nouvelle-Calédonie (3) Institute of Natural Resources, Massey University, Ecology Building PN 624, Private Bag 11 222, Palmerston North, 4442, New Zealand (4) UMR 7208, Ichtyologie, Département Milieux et Peuplements Aquatiques, Muséum National d'Histoire Naturelle, CP 26, 57 rue Cuvier, 75005 Paris *pg@mnhn.fr Biologists too often treat so-called relict taxa as collectors do with antiques in a street market. That way, relict taxa are frequently seen as fascinating survivors from the good old days and are even naively and illogically viewed as living ancestors. This perception is painfully misleading for evolutionary biology and biogeography. The notion of a living ancestor has been dismissed in evolutionary biology long ago, but the same methodological advance has not yet been made in biogeography. For that reason, relicts are still often portrayed as indicating centers of origin or at the very least biogeographical refuges. To improve the situation, we elaborate on how to define and diagnose a relict, either geographical or phylogenetic or both, and how to treat the information it actually provides for understanding the evolution and spatial distribution of a clade. In this respect, relicts are merely interesting because they indicate extinctions at a regional level. They also have a great value in conservation biology because of their high phylogenetic informative content. Several case studies are taken from New Caledonia and New Zealand to exemplify misleading past reasoning and to draw some potentially more fruitful directions of research. The origin of the New Zealand flora; a devil’s advocate approach LEHNEBACH C.* (1); WAGSTAFF S. (2) and TREWICK S. (3) (1) National Museum of New Zealand, Te Papa Tongarewa (2) Lancare Research, Lincoln (3) Massey University, Palmerston North *carlosl@tepapa.govt.nz The origin of New Zealand flora and fauna has been strongly debated over the years with a strong preference for an ancient, vicariant Gondwanan history. However, results from numerous phylogenetic and biogeographic studies indicate the current biodiversity is mainly the product of recent colonisation events from different land masses followed by morphological and ecological diversification. Many of these colonisation events postdate the break-up of Gondwanaland; and some authors have even suggested there are no truly vicariant Gondwanan elements in the New Zealand flora at all. Despite the evidence that dispersal has been a major process leading to the formation of the New Zealand flora, acceptance has been hindered by preconceptions on plants dispersal capabilities and evidence from the fossil record. Some of the main arguments used to refute dispersal are: 1) If seeds have no clear mechanisms or morphological adaptation to facilitate long distance dispersal then it is unlikely this has occurred. 2) if long distance dispersal has occurred in a plant group this can only occur in the direction of the prevailing winds and 3) If an extant taxon is represented by a New Zealand fossil record it has always been in New Zealand. In this talk we will address these three arguments and will challenge these assumptions using results from current phylogenetic, biogeographic and ecological studies. The future of disturbance ecology. Adapting to global environmental change: what role for disturbance ecology? VEBLEN T.T.* (1); HOLZ A. (1); PARITSIS J. (1); RAFFAELE E. (2); KITZBERGER T. (2) and BLACKHALL M. (2) (1) Department of Geography, University of Colorado, USA (2) INIBIOMA-CONICET and Laboratorio Ecotono, Universidad del Comahue, Bariloche In the context of climate warming and ecological forecasting, a major research challenge is to determine how disturbance events and their interactions alter ecosystem susceptibility to climate-induced ecological changes. Conceptual frameworks for investigating changes in climate-related disturbance regimes, such as wildfire activity, emphasize the potential of land-use practices to accelerate ecological change and potentially lead to abrupt regime shifts. In the Patagonian-Andean region, land management practices involving livestock management, introduced plant and animal species, and fire management (both ignition and exclusion) potentially alter ecosystem susceptibility to climate-induced changes in wildfire regimes. A combination of land-use practices appears to be contributing to the replacement of relatively fire-resistant native forests by more fire prone vegetation. While regional warming and drying trends are highly likely to increase future wildfire activity in Patagonia, available knowledge derived from studies of disturbance ecology in these ecosystems usefully informs options for adaptation to and mitigation of climate impacts on wildfire potential. Disturbance in subtropical dry forests across contrasting social contexts JOBBAGY E. (1); BALDI G.* (1); VERON S. (2) and DIBELLA C. (2) (1) Universidad Nacional de San Luis & CONICET (2) Insituto de Clima y Agua - INTA & CONICET *jobbagy@gmail.com Increasing human control over ecosystems claims for a better projection of ecological knowledge across social gradients. How are disturbance regimes and impacts affected by population density, welth, industrialization or connection to markets? By spanning diverse social contexts, subtropical dry forests (STDF) offer a valuable arena to explore this question. Based on remote sensing tools we characterized cultivation and fire patterns and their influence on vegetation structure and net primary productivity (NPP) across precipitation gradients under contrasting social contexts. STDF regions of convergent climate and original vegetation structure were identified in five continents. Cultivation introduced higher crop diversity and more complex landscape patterns in Asia and Africa were denser rural populations rely on local production. The opposite occurred in Australia and the Americas were production targetted national/global markets. Fire density was higher in forests than in croplands and maximum in areas with intermediate cultivation (1-10% coverage). Fires consumed ~5% of the NPP of STDFs in Africa, South America and Australia, but <1 % in Asia and North America. In most regions croplands had lower NPP than natural vegetation, particularly towards humid zones. Preliminary generalities about the role of the social context shaping fire and cultivation regimes as well as ecosystems structure and function can be established. Future approaches to disturbance ecology across severity and land use gradients WALKER L.* University of Nevada Las Vegas *walker@unlv.nevada.edu Disturbance, or the relatively sudden and discrete loss of biomass or function, is an integral part of every ecosystem. Advances in understanding ecosystem responses to natural disturbances and traditional knowledge about manipulating disturbances from agriculture can be combined to address the novel suite of disturbances now created by humans. Complex interactions among disturbances at many overlapping spatial and temporal scales can be examined across severity and land use gradients. The gradient approach applies traditional ecological tools to address differential conditions of stability and fertility, degrees of biological legacy and rates of successional recovery to modern concerns about socio-economic consequences of disturbance and the sustainability of ecosystem services. Impact of grazing on the species composition of grasslands and savannas OESTERHELD M.* and SEMMARTIN M. IFEVA, Fac Agronomía, UBA/CONICET *oesterhe@agro.uba.ar The impact of grazing on the species composition and diversity of grasslands and savannas is highly relevant to both disturbance ecology and ecosystem management. A critical issue is that the magnitude of the impact of grazing differs widely among plant communities. This variation has been accounted for by the primary productivity and the evolutionary history of grazing of the community being grazed. However, primary productivity covaries with grazing intensity, and determining the evolutionary history of grazing of a given plant community poses some practical problems. We present a conceptual model that connects primary productivity and evolutionary history with the basic factors that determine the composition of a plant community: species availability in the regional pool, dispersal, and interaction with abiotic and biotic factors. Linking disturbance and ecosystem services: Conceptual foundations for sustainability in the 21st century WILLIG M.* University of Connecticut *michael.willig@uconn.edu Disturbance, whether caused by natural or anthropogenic agents, initiates a cascade of temporal changes in the composition and structure of communities, as well as in the ecosystem processes that arise from the interactions by constituent species with matter and sources of energy. Regardless of seral stage during subsequent succession, these ecosystems provide a plethora of services associated with supporting, provisioning, regulating, and cultural functions. In concert, these services lead to the well being of human society (e.g., security, health, materials for a good life, enhancement of social relations). Long-term management for sustainability requires knowledge about the way in which human activities alter the dynamics of ecosystems and the services that they provide to humans. As such, a multidisciplinary perspective is critical, as tradeoffs likely exist when any particular management decision affects land, water, air, biotic, and cultural resources differently in terms of current, option, and bequest value. Equally important, it is necessary to understand how knowledge about and valuation of services influence decisions about management, conservation, and policy. Sustainability at the local, national, regional, and global scales thus requires a greater appreciation of the varied ways in which disturbance affects the spatial and temporal dynamics of socioecological systems (i.e., coupled human and natural systems). Societal behaviors and disturbances: their synergistic effects on vegetation dynamics in urban woodlands CARREIRO M. (1) and ZIPPERER W.* (2) (1) Biology Department, University of Louisville, USA (2) USDA Forest Service, Gainesville, FL, USA *m.carreiro@louisville.edu Disturbance theory has been developed principally for natural ecosystems in non-urban landscapes. Adapting this theory to urban landscapes requires not only an accounting of natural and anthropogenic disturbances, but also societal responses to disturbances. In other words, understanding the impacts of a disturbance event on the recovery of natural remnant ecosystems in cities must encompass a socio-ecological perspective. The nature of societal exchanges with forested park remnants within cities and their outcomes on the vegetation dynamics of these remnants will be explored using examples from northern and southern hemispheres. We use the adaptive cycle and panarchy framework as a theoretical foundation to develop a disturbance typology for urban landscapes. To do so, we will report on how historical legacies (biophysical and social) and social context (e.g., human demographics, social connectivity, local expertise, citizen activism, laws) interact with the ecological content of woodlands to affect their recovery direction and rates. Exploring how urban people respond to damage sustained by their green infrastructure may help identify where adaptive capacity resides for improving the quality and sustainability of urban green infrastructure and the ecosystem services they provide. These services may be especially important contributors to the resiliency of urban landscapes as disturbance regimes change with increasingly variable and unpredictable regional climates. Austral Cenozoic floras and their value in elucidating modern plant distribution. Early Paleocene Macrofloras of Patagonia and their Significance for Austral Biogeography and Biodiversity IGLESIAS A.* (1); WILF P. (2); JOHNSON K.R. (3); SLINGERLAND R. (2) and GANDOLFO M.A. (4) (1) Facultad de Ciencias Naturales y Museo -UNLP (2) Pennsylvania State University, Geosciences (3) Denver Museum of Nature and Science (4) Department of Plant Biology, Cornell University *ari_iglesias@yahoo.com.ar We report on new and rediscovered macrofloras from southern Chubut Province, Patagonia, Argentina that represent the first stratigraphically controlled and quantitatively collected Paleocene macrofloras from southern South America. The floras provide critical information about floristic diversity and composition following the Cretaceous-Paleogene boundary (K-T) and prior to the extremely high plant diversity in Patagonia by the warm early Eocene. The collections, from several sites in the estuarine Salamanca Formation and the overlying, fluvial Peñas Coloradas Fm., date from ca. 61.7 Ma, about ~4 m.y. after the K-T boundary. The floras represent varied paleocommunities preserving more than 50 species of angiosperm leaves as well as flowers, fruits and seeds, ferns, and conifer leaves and reproductive structures. Among the lineages identified are: Akaniaceae, probable Nothofagaceae, and Nageia-like and other Podocarpaceae leaves, as well as Lygodium, Araucariaceae, Palmae, Fabaceae, Menispermaceae, Rosaceae, Lauraceae, Salicaceae, Sapindaceae, Malvaceae, Urticaceae, and a Brassicales flower. Although the biogeographic signature of the flora is clearly gondwanic, there appears to be greater compositional distinctiveness from coeval Australian floras than is seen in Patagonian Eocene floras, suggesting some degree of endemism after the K-T followed by increased interchange across Antarctica with Eocene warming. How New Zealand Eocene, Oligocene and Miocene macrofossil and pollen records help explain modern plant distributions LEE D. (1); BANNISTER J. (1); CONRAN J. (2) and MILDENHALL D.* (3) (1) University of Otago (2) University of Adelaide (3) GNS Science, New Zealand *daphne.lee@otago.ac.nz The modern New Zealand flora has a remarkably low number of families and genera in relation to land area. Well-preserved macrofossils and pollen from New Zealand suggests a much more diverse flora in Eocene, Oligocene and Miocene times. A Late Eocene forest with fern understorey was dominated by conifers, †Casuarinaceae, Nothofagus, Proteaceae, and mesothermal angiosperms including palms (aff. † Calamus), †Cupania and †Austrobuxus. Leaf fossils in a Late Oligocene oligotrophic bog show that Agathis , Dacrycarpus, Dacrydium, Podocarpus and Phyllocladus coexisted with diverse angiosperms including Nothofagus, †Gymnostoma, Cunoniaceae, Ericaceae, Sapindaceae and several Proteaceae. Pollen data add Meliaceae, Myrtaceae, Onagraceae and Rubiaceae. Early Miocene monocot macrofossils include Astelia, Cordyline, Ripogonum and Typha as well as the oldest fossils of Orchidaceae and Luzuriagaceae. This flora was dominated by Lauraceae (†Cryptocarya, †Endiandra and Litsea), but other families include Araliaceae, Cunoniaceae, Elaeocarpaceae, Euphorbiaceae (†Mallotus), †Menispermaceae, Myrsinaceae, Myrtaceae, Proteaceae and †Sterculiaceae. Many ferns, conifers, and Nothofagus are from lineages with Gondwanan ancestors, whereas other taxa show links to Australia (e.g., †Gyrostemonaceae), New Caledonia (e.g., †Beauprea) and South America (e.g., Luzuriaga). Taxa marked [†] are now extinct in New Zealand, but they indicate much wider biogeographic ranges for many families and genera in the past. Leaf margin analysis: a new model for South American paleoclimate reconstruction HINOJOSA L.F.* (1); PéREZ M.F. (2); GAXIOLA A. (3) and SANDOVAL I. (1) (1) Universidad de Chile. I.E.B. (2) Pontificia Universidad Católica de Chile. I.E.B. (3) Pontificia Universidad Católica de Chile. CASEB *lfhinojosa@uchile.cl The relationship between the proportion of species with entire leaf margin (pE) in a woody local flora and mean annual temperature is considered one of the most powerful tools for estimating paleotemperatures. However, the extent to which pE is determined by historic factors rather than climate has seldom been explored. Using foliar material from 30 sites located between 32ªS and 44ªS we found the relationship between pE and MAT for southern South America forests and compared it with other models from Southern and Northern Hemispheres to assess the influence of historical legacy on the pE-MAT relationships. We further evaluated the relevance of historical constraints in determining pE. We found a significant pE-MAT relationship for Chilean plant species, which coincide with South America, but differed from northern hemisphere and Australian species. We found an association between presence/absence of entire leaf margin and phytogeograhic elements and significantly phylogenetic constrains in the margin character. We blended Chilean and Tropical South American datasets to establish a new regional model from which more reliable temperatures can be predicted. We confirm that standard pE-MAT relationships based on global datasets hold along the strong Chilean climatic gradient. However, statistical differences between Chilean and regional models highlight the relevance of the use of regional pE-MAT in estimating paleotempratures. FONDECYT 1090339-IMEB P05-002. Proteaceae leaf fossils and austral distributions CARPENTER R.* University of Adelaide *raymond.carpenter@adelaide.edu.au Dating of lineage diversifications based on molecular phylogenetic evidence supports Gondwanan vicariance for some taxa of Proteaceae, but shows that for other taxa dispersal events must be invoked. Fossils assignable to Proteaceae are relatively abundant in southern hemisphere Cretaceous and Cenozoic sediments and include pollen, leaves, fruits and even flowers. Here I focus on aspects of the leaf fossil records of Australia and New Zealand. How useful are these fossils for interpreting past and present distributions? For instance, is there support for vicariance vs dispersal scenarios to explain the distributions of particular taxa? So far, the oldest records of Proteaceae foliage are from Paleocene sediments: Cretaceous sediments known to contain angiosperm leaves do not have recognisable Proteaceae. Small, pinnately lobed Banksia leaves occur at an Australian late Paleocene site, and similar leaves have recently been found in the Oligo-Miocene of New Zealand. These fossils demonstrate a past wider distribution for a now definitively Australian genus. Examples are discussed of several Grevilleoideae fossils (notably Embothrieae and Orites) that are consistent with Gondwanan distributions between South America and Australia. These specimens are known from floras that often include diverse conifers, Gymnostoma (Casuarinaceae), Lygodium, Cunoniaceae, Nothofagus and Myrtaceae. Overall, more research is needed to place Proteaceae leaf fossils in a phylogenetic context. Review of the Argentinean monocotyledon fossil record GANDOLFO M.A.* (1) and ZAMALOA M.C. (2) (1) Cornell University (2) Univerisdad de Buenos Aires *mag4@cornell.edu The monocotyledons constitute roughly 22 % of the angiosperms, with approximately 3.000 genera and 65.000 species; including several economically important groups. Due to many reasons, they have a low likelihood of being fossilized and this is reflected in the sparse known fossil record for the group. Herein, we revise the fossil Argentinean monocot fossil record from the late Aptian (~112 ma) to the Miocene (~ 5 ma). Fossils include pollen, leaves, phytoliths, fruits and trunks. The first occurrences are represented by pollen fossil collected at Aptian-Albian outcrops (La Cantera Fm, San Luis Province). Families with reliable micro and mega fossil record are Araceae, Cyperaceae, Poaceae, Restionaceae, Potamogetonaceae, Hydrocharitaceae, Sparganiaceae/Typhaceae, and Arecaceae. Within the record, there are some taxa, such as Liliacidites and Stellatopollis (pollen) and leaves with parallel venation, with highly probable monocot affinities, however more comprehensive studies on these fossils are needed to assess and confirm their taxonomic placement. Workshop Tectonic evolution of Patagonia and adjacent terrains: implications to the early divergence of the austral biota Geological evidence for paleogeographic relationships between Patagonia and the Antarctic Peninsula since the Permian. HERVé F.* Departamento de Geología, Universidad de Chile, Casilla 13518 Correo 21, Santiago Chile *fhervé@cec.uchile.cl The more recent models which depict the paleogeographic relationships between Patagonia and the Antarctic Peninsula are based in the study of the magnetic signatures on the Southern Ocean floor. They indicate that the Antarctic Peninsula was located west of Patagonia in the Middle Jurassic. However, similar high grade metamorphic rocks in both areas, suggest that they were already contiguous in the Permian. Extension started in the Middle Jurassic, generating a volcano tectonic rift zone. One of these rifts developed into the Rocas Verdes Basin, a quasi oceanic back arc basin which was the northern continuation of the Weddell Sea. The Rocas Verdes Basin was closed and inverted during the Cretaceous, initiating the development of the Magallanes foreland basin, a depocenter throughout the late Mesozoic and the Cenozoic. It is speculated that another basin- the Rocas Azules basin - developed between the present Antarctic Peninsula and the Patagonian mainland, whose oceanic floor was subducted below Patagonia during the Cretaceous giving rise to a blueschist belt. Then Patagonia and the Antarctic Peninsula drifted apart. Paleomagnetic studies suggest that it was South America that moved northward. During this process the circumpolar current was established in the southern oceans, giving rise to conditions that made the late Cenozoic glaciations possible. The sedimentary record of the Magallanes and Larsen basins should also record this event of global consequences. Linking geological and biological evolution: phylogeographical evidence on Nothofagus reflects the complex paleogeography of Patagonia PREMOLI A.C.*; MATHIASEN P. and ACOSTA M.C. Universidad Nacional del Comahue-Centro Regional Universitario Bariloche and CONICET-INIBIOMA, Quintral 1250, 8400 Bariloche, Argentina *apremoli@crub.uncoma.edu.ar Distribution patterns of extant austral elements, although recognized to have links with Tertiary evolution, have been mostly explained in relation to Neogene events. We tested the hypothesis that living species of subgenus Nothofagus, found at present as continuous populations in southern South America and a fossil record occurring in all southern lands, consists of ancient lineages. We predict that phylogeographic paterns will be congruent with paleogeographic features of austral land masses. We performed a detailed multi-species phylogeographic analysis using sequences of three chloroplast DNA non-coding regions on a total of c. 200 populations along entire ranges of the five extant species within subgenus Nothofagus which are thought to have endured ice ages in multiple local refugia and we dated the resulting intraspecific phylogenies. Our results show a major genetic discontinuity between populations of all five studied species at mid latitudes of Patagonia that occurred 40 Myr ago. We hypothesize that this allopatric divergence arose due to long-lasting paleobasins that impeded transoceanic dispersal. Also that land-based dispersal occurred using pre-Miocene mountains as corridors throughout at least two connections with Antarctica. We show the utility of phylogeographical reconstruction shedding light on complex paleogeographical features of Paleogene landscapes shaping the gene pool of ancient cold hardy species that were not reset by glaciations of the Neogene. Paleomagnetic constraints on the paleolatitudinal evolution of Patagonia in the last 200 million years RAPALINI A.E.* INGEODAV, Departamento de Ciencias Geológicas, FCEN, Universidad de Buenos Aires – Conicet. *rapalini@gl.fcen.uba.ar Quantitative paleogeographic reconstructions since the Jurassic can be obtained by two complementary methods: i) the ocean floor magnetic anomalies and ii) the apparent polar wander paths (APWP). Whereas the first can achieve high-resolution reconstructions of the past relative positions of the different plates, the second is the only method that allows assigning absolute paleolatitudes. Adequate combination of both can significantly improve the amount and quality of paleomagnetic data and allow more precise paleogeographic reconstructions, based on the APWPs. Since there is no geological or paleomagnetic evidence of any major displacement between Patagonia and the rest of South America since the Triassic, paleomagnetic data useful for the latter can be used to determine the paleolatitudinal evolution of Patagonia. Since the break-up of Pangea, South America has undergone relatively minor displacements with respect to the Earth spin axis, remaining as the most “stable” Pangea fragment. This translates into relatively minor paleolatitudinal changes for Patagonia since Middle Jurassic. At least two long stand-still periods, only characterized by a “westward” drift of South America, are observed, from 125 to 100 Ma, at latitudes similar to present-day, and between 85 and 40 Ma at latitudes some 5° higher. A controversial extremely rapid shift in paleolatitude of over 20° for Pangea during the earliest Jurassic and its implications for Patagonia will also be discussed. South American – Antartic fossils are evidence of an old history of the living flora of Patagonia. ROMERO E.J. (1) and ZAMALOA M.D.C. (2) (1) Museo Argentino de Ciencias Naturales Bernardino Rivadavia, CONICET. (2) Facultad de Ciencias Exactas y Naturales, UBA During the Paleogene several phytogeographical Provinces were present in Patagonia, changing through time in response to tectonic changes, early Andean uplift, oceanic transgression on land, and isostatic movements. Most important were the “Subantarctic Paleoflora” and the “Mixed Paleoflora” (Troncoso & Romero), which are the forerunners of the present Subantartic Province and Chaco Province in South America. The Subantarctic Paleoflora Forest developed in the western uplands, along the Pacific margin of Gondwana, in the high lands of the Andes, the Transantarctic Mountines and the Australian Alps. It was probably most important in the Antarctic continent, and recent evidence shows that it reached the Atlantic coasts in Patagonia during the Early Miocene. The Mixed Paleoflora was present in the eastern lowlands of Patagonia. Recent evidence has shown that they shared several important taxa with Tertiary and present forests in Australia. Among them Gimnostoma, Akania, Orites, Eucalyptus. Therefore, it can be hypothesised that an extended “Southern Paleogene Warm Temperate Forest” was present in the Southern Hemisphere. It extended in the lowlands, from the Atlantic coasts in South America, to the Weddell coasts in Antarctica, to the Indic Ocean coasts in Australia. We are characterizing it here as a lowland forest with mainly Gondwana lineages that gave origin to the open, seasonally dry forests of the Chaco Region in South America, and similar areas in Australia. Tectonic evolution of the Patagonian Andes RAMOS V.A.* Universidad de Buenos Aires, Argentina *andes@gl.fcen.uba.ar The uplift of the Patagonian Andes is controlled by different geological and tectonic processes that show that climate has had an important role, not only in the carving of the landscape, but also controlling the uplift mechanisms through time. The spatial and temporal constrains of the Neogene uplift are established by the distribution and age of the molassic synorogenic deposits. This uplift produced an increased aridity of the extra-Andean Patagonia and profound climatic changes that triggered the extinction of part of the biota. The interaction between climate and tectonics can be also addressed in three distinct topics: (1) the present structural volume of the Patagonian Cordillera is relatively small when compared with the central segments of the Andes. This difference has been attributed to the sediment fill of the trench, which lubricates the friction in the subduction channel and therefore produced less coupling between the continental upper plate and the subducted slab. This sediment supply is related to the dominant wet winds from the southwest, which produce the rain shadow and asymmetric erosion in the Patagonian Cordillera; (2) the continuous batholith belt is also a consequence of uplift and climatic interaction. As soon as the Patagonian Cordillera initiates its uplift in Miocene times, most of its western slope was subjected to an extreme erosional gradient as a consequence of rain shadow. As a result of that the magmatic arc was deeply eroded and the batholith was denudated; and (3) the Patagonian Cordillera has an anomalous isostatic rebound, near to 20 mm/yr along the axis of the cordillera, which has been associated with the LGM (Late Glacial Maximum) deglaciation. This anomalous behavior is related to a hot upper mantle, generated as a consequence of several episodes of ridge subduction, which favors the important isostatic rebound. Because of that, this segment of the Andes records the first glaciations during the late Cenozoic. Presentations Evolution Darwin in southern South America: evolutionary thinking before the galapagos ARMESTO J. (1); POHL N. (2); ROZZI R. (3) and TAMBUTTI M.* (4) (1) Pontificia Universidad Catolica de Chile (2) Fundación Senda Darwin-Chile (3) Universidad de Magallanes (4) Instituto de Ecología y Biodiversidad *jarmesto@bio.puc.cl The development of Darwin’s ideas during the voyage of the Beagle has been the subject of much debate, analysis and speculation among scholars. The most widely held about this problem, called the “Eureka” hypothesis by S. J. Gould, suggests that the idea of evolution struck Charles Darwin’s mind as a “bolt of lightning”, upon discovery of the Galapagos Islands finches. However, a more parsimonious explanation, consistent with Darwin’s own belief, is that the theory about the origin of species derives from a more complex process of data gathering, analysis and synthesis, plus insights from various disciplines. Here, we discuss the frequently overlooked contribution to evolutionary thinking of his observations, hypotheses, and serendipitous findings made while traveling for more than a year through southern, central and northern Chile. We argue that Darwin’s Chilean experience was instrumental for refining his ideas, derived mainly from Lyell’s geology, about the timeframe and gradual nature of the changes that originate massive continental features. Being witness to volcanic eruptions and a major earthquake led him to challenge the ideas of stability in geology and biology. Finally, a dedicated 8-yr study of the systematics of living and fossil cirripedia, based on a tiny barnacle found in the Chonos archipelago, allowed him to become a flourishing biologist, with a revolutionary and compelling view of the history of life. Gondwana revisited: new insights in the phylogenetic relationships within the Orthalicoidea (Mollusca, Stylommatophora) BREURE A.S.H.(.*; GROENENBERG D.S.J.(. and SCHILTHUIZEN M.(. NLCB-Naturalis, Leiden, Netherlands *breure@xs4all.nl The land snails classified within the Orthalicoidea are present on different southern continents. They are most diversified in the Neotropics (~ 1475 species), but also occur in South Africa (3 species), Australia (~ 40 species), and New Zealand/Melanesia (~ 100 species). Systematically they are grouped into five families (Amphibulimidae, Bulimulidae, Orthalicidae, Odontostomidae and Placostylidae). These are partly considered as subfamilies by various authors. Based on molecular data, an analysis with mitochondrial marker CO1 and nuclear marker ITS-1/28S has been made of the relationships within the superfamily. However, the number of genera covered in the molecular dataset is limited and more research is needed to fully elucidate the relationships within and between the families mentioned above. Our preliminary results, based on mtDNA, suggest that these groups are indeed related and some of them (Orthalicidae, Odontostomidae and Placostylidae) are assumed to be monophyletic. In the group considered to be Bulimulidae, several clades are probably paraphyletic. If the preliminary results are corroborated by further analyses based on nDNA, conclusions on taxonomical implications can be made. Additional analyses are also required before phylogeographical conclusions may be drawn. Genetic and morphological diversification of Galaxias maculatus in Northern Patagonia CARREA C.* (1); BARRIGA J.P. (1); CUSSAC V.E. (1) and RUZZANTE D.E. (2) (1) INIBIOMA Universidad Nacional del Comahue-Conicet (2) Dalhousie University *cecilia.carrea@gmail.com Objectives: To study the influence of life history, ecology and history on the diversification of G. maculatus in Patagonia. We hypothesized that restrictions in gene flow may lead to local adaptation and population divergence. Methods: Patterns of genetic, morphological and meristic variability in G. maculatus were examined using microsatellites, geometric morphometrics and meristic counts. Eleven localities differing in connectivity were sampled within Lakes Nahuel Huapi, Correntoso and Victoria Island. Results: A bayesian analysis identified K=4 genetic clusters, corresponding to localities in Victoria Island (2), Correntoso Lake (1), and Nahuel Huapi lake (1). Morphology and genetics were correlated with each other but neither was correlated with geographical distance. G. maculatus from Lake Redonda exhibited lower genetic diversity, lower meristic counts and different morphology than the other locations. No genetic or morphological structure was detected within Nahuel Huapi or Correntoso lakes. Conclusions: G. maculatus within Redonda Lake has likely been isolated since the drop in water level of a paleolake , ca. 16.000 BP. Divergences of Larga and Correntoso populations are explained by life history and predator presence in the streams connecting them with Lake Nahuel Huapi. Finally, the lack of genetic structuring within Nahuel Huapi and Correntoso lakes suggests this species larval limnetic habit exerts an important homogenizing effect on gene flow within lakes. Molecular phylogeny of Poa supersect. Homalopoa with emphasis in Austral sections. GIUSSANI L.M.* (1); SCATAGLINI M.A. (1); NEGRITTO M.A. (2); GILLESPIE L.J.,. (3); ANTON A. (4); REFULIO-RODRIGUEZ N.F. (5) and SORENG R.J. (6) (1) Instituto de Botanica Darwinion-CONICET, Labardén 200. CC 22 (2) Universidad de Concepción. Dpto. Botánica. Casilla 160-C, Concepción, Chile (3) Canadian Museum of Nature, PO Box 3443, Station D, Ottawa, Ontario, Canada (4) IMBIV-CONICET. Universidad Nacional de Córdoba. CC 495, Córdoba, Argentina (5) Department of Biology. University of Washington. Campus Box 355325, Seattle, WA USA (6) National Museum of Natural History, Smithsonian Institution, Washington DC, USA *liligiussani@yahoo.com.ar Poa L. is one of the two largest genera of grasses with more than 500 species worldwide. The genus has been extensively studied and major phylogenetic relationships have been explored. Recently, it has been divided into five subgenera and 28 sections. Poa is characterized by having different reproductive systems, from hermaphroditism to dioecism. Most of the variations in floral arrangements in Poa are concentrated in sections and informal groups of Poa subg. Poa supersect. Homalopoa, and gynomonoecism, gynodioecism and dioecism are frequent among species of America and New Zealand. To investigate relationships within the monophyletic supersect. Homalopoa and to look for trends in the evolution of the reproductive system, we included more than a hundred species of supersect. Homalopoa. Several markers: ITS and ETS (nucleous), and trnT-L-F, rpoA, and rpl16 (chloroplast) were sequenced and analysed using parsimony. Although basal relationships are not resolved and there is little resolution within major clades, several well-supported groups are recovered and discussed. Dioecism would have appeared at least three times independenly within Homalopoa. Results confirmed the monophyly of Dioicopoa and two other dioecious clades with species of Madropoa. Direct relationships among dioecious and exclusively pistillate species are not supported. Gynomonoecism and gynodioecism appear in at least six clades, and strictly pistillate apomicts appear several times in different clades. Monotypic genera of the Asteraceae in the Cape Floristic Region - evolutionary dead-ends? GOODMAN (NEE CRON) G.* University of the Witwatersrand, Johannesburg, South Africa *Glynis.Cron@wits.ac.za Of the c. 128 genera in the Asteraceae in the Cape Floristic Region (CFR) of South Africa, 25 are monotypic (19.5%). Seventeen of these monotypic genera are endemic to the CFR, 22 to the winter rainfall region (Western and Northern Cape). In a region as diverse as the CFR, and where climate, edaphic and topographic variability have promoted speciation and even radiation in certain genera, why are such a large proportion of the asteraceous genera monotypic? Are they evolutionary ‘dead-ends’ or instances of incipient speciation? This study aims to gain insight to answers to this question by investigating morphological aspects related to survival (life history strategies) and reproductive strategies, as well as distribution, location, habitats, and phylogenetic position of these monotypic genera. Patterns emerge reflecting morphological specialization for isolated, extreme habitats, as well as limited distribution and habitat specialization. Phylogenetic patterns indicate that many of these monotypic genera are not the most recently evolved within a clade, but frequently diverge near the base of a clade and/or are sister to a clade in which further diversification has occurred in other genera. cpDNA analysis suggests that the maternal parent of peanut ( Arachis hypogaea l.) belongs to the a genome GRABIELE M.*; ROBLEDO G.A. and SEIJO J.G. Instituto de Botánica del Nordeste (UNNE-CONICET) *marinagrabiele@hotmail.com The cultivated peanut, a South American native cultigens, is one of the major oilseed crops of the tropics and subtropics. This natural and well-established allotetraploid (2n=4x=40, AABB) is included in section Arachis together with a wild allotetraploid and 29 wild diploid species. Researchers generally agree that the wild progenitors of peanut belong to section Arachis, however, there is still uncertainty on which A or B genome species has been the maternal parent. In order to address this particular topic of the genetic origin of peanut, we investigated the variability of cpDNA sequences in A. hypogaea and in eight closely related wild diploids. For this purpose, six no-coding cpDNA regions were PCR-amplified and sequenced. A total of 5200 bp were manually edited, and the substitutions as well as insertions/deletions were recorded. The comparative analysis of the sequences showed that species with A genome are more closely related to A. hypogaea and A. monticola than those with B genome. These results demonstrated that the maternal diploid parent of peanut, and its wild tetraploid ancestor, belongs to the A genome species group of section Arachis. Phylogeny, distribution and biogeographic origin: a morpho-architectural approach from Valdivian trees. GROSFELD J.* (1); MAGNIN A. (1); GEREA M. (1) and BARHéLéMY D. (2) (1) INIBIOMA-CRUB (2) INRA, UMR AMAP *javigros@yahoo.com.ar Growth, branching and architecture patterns of tree species are related to their phylogenetic origin and their spatial, geographical and ecological distributions. We studied main aspects of morphological and architectural features of several Valdivian tree species (belonging to the genera Aextoxicon, Laureliopsis, Embothrium, Gevuina, Lomatia, Luma, Myrceugenia, Maytenus, Raukaua , Dasyphyllum, Caldcluvia, and Weinmannia) from Gondwanian, Neotropical or Pantropical lineages. In all species we observed a marked evolution of the major morpho-architectural variables along individuals ontogeny. Bud structure may vary from naked to covered by cataphylls and/or stipules, and may be largely related to the distribution of these species in Argentina. Periodical monitoring during seasonal growth showed a significant correlation between primary growth rate and some environmental factors for several of the species studied. Some of the morpho-architectural traits studied could explain ecological adaptations. New data from related species belonging to other geographical areas could help elucidate the determinism of these morphological variations and/or adaptations. Ongoing speciation in the killifish Orestias ( Agassizii complex) in the chilean altiplano. GUERRERO C.J.* (1); PEñA F.; VILA I. (2) and POULIN E. (1) (1) Instituto de Ecologia y Biodiversidad U.de Chile (2) Laboratorio de Limnología.U. de Chile *claudiajimenaguerrero@gmail.com Four species have been described,O. parinacotensis in the Parinacota cushion bog, O. chungarensis in Chungará Lake, O. piacotensis in Piacota Lagune and O. laucaensis in Cotacotani Lagune and Lauca River. During Pleistocene-Holocene periods the Chilean Altiplano was affected by strength volcanic and tectonic activity that lead to the formation the rivers and lakes. The aim was to determine geographic distribution of genetic diversity among these species and evaluate ongoing differentiation process. Samples were collected from Parque Nacional Lauca. Dloop DNA was amplified and sequenced. Genetic diversity,genealogic relationships,haplotype network,demographic history was calculated.Genetic diversity varied among species. O. laucaensis presented greatest number of haplotype. O. parinacotensis showed greatest haplotypic diversity. O. chungarensis, O. piacotensis and O. laucaensis showed a low but clear separation with a central haplotype with short ramifications. O. parinacotensis network showed a scattered distribution. FST values were significant for all species. Population expansion time indicated that the origin of different Orestias species was during Pleistocene when changes in the river Lauca basin originated the Chungará basin. molecular analysis showed the existence of genetic differentiation among Orestias morphospecies.Genetic distances among taxa are low and could reflect the recent diversification process iniciated during the Pleistocene-Holocene periods. Ecological differentiation between the sister species Schizanthus hookeri and S. grahamii : the LEON C.* and PéREZ F. Pontificia Universidad Católica de Chile *fefapt@yahoo.com Ecological speciation occurs when barriers to gene flow between populations evolve as a result of ecologically-based divergent selection. In plants, the source of divergent selection can be environmental features that lead to local physiological adaptations. In this work we examined the history of ecological differentiation between two species, S. hookeri and S. grahamii that grow in high Andes of Chile and Argentina. Despite that the distributional range of these species overlap, they rarely occur sympatrically. In general, S. hookeri is found in dry slopes, whereas S. grahami occurs in humid ravines. In order to assess the role played by the abiotic factors in the speciation, microhabitat preference and foliar traits related to drought resistance of both species were compared. Samples of soil and leaves of each species were collected in a locality where both species co-occurs. Moisture content, soil fertility, foliar area, leaf mass per area (LMA) and stomatic density were measured. Moisture content, ammonium concentration and nitrate concentration were significantly lower in soil samples of S. hookeri. Accordingly, LMA of S. hookeri was significatively lower than LMA of S. grahamii. This species presented the same stomata quantity on both sides of leaf, while S. hookeri had the most number of stomata on abaxial side. These results suggest that S. hookeri and S. grahamii are adapted to different abiotic conditions, which could play an important role on speciation. Phylogeography of Calibrachoa heterophylla (sendtn.) wijsman: an endemic herb in the coastal plain of south Brazil MADER G.* (1); LORENZ-LEMKE A.P. (2); SALZANO F.M. (1); BONATTO S.L. (3) and FREITAS L.B. (1) (1) UFRGS (2) UFMS (3) PUCRS *geraldomader@pop.com.br Calibrachoa heterophylla (Solanaceae) dwell in sandy fields at the Coastal Plain of Rio Grande do Sul Brazilian state (CPRS). Cyclic climatic and habitat occurrence oscillations in the Pleistocene had high influence on the evolutionary history of many biological groups. Molecular techniques and analytical methods bring important insights into likely evolutionary scenarios. The objective of this work is characterize the genetic diversity of C. heterophylla, to better understand its evolution and phylogeographic patterns. We sampled 250 individuals from 16 populations, of which we obtained sequences of the plastidial spacers trnH-psbA and trnS-trnG. The sequences were analyzed with several populational methods. The haplotype network shows clear geographical structure and high FST. We also found significant correlation between the genetic and geographical distances. Samova analysis found two likely barriers to gene flow separating three groups of populations. The limited seed dispersal coupled with the maternal inheritance of the plastidial markers used may be a likely explanation for the low intrapopulational diversity found. The high divergence found between some groups could not likely be explained has having originated in the CPRS, as this region of geologically very recent. Consequently, already differentiated lineages should have colonized the region perhaps by different routes and stayed isolated due the barriers that coincide with the path of ancient river channels. Interspecific and intergeneric hybridization among South-American Discaria and Ochetophila (Rhamnaceae) MEDAN D. (1); ARBETMAN M.* (2); CHAIA E. (3) and PREMOLI A. (2) (1) Facultad de Agronomía de la U.B.A., Buenos Aires (2) Laboratorio Ecotono, U.N. Comahue, Bariloche (3) C.R.U.B., U.N. Comahue, Bariloche *diemedan@agro.uba.ar In gondwanic Discaria Hook., phenotypically intermediate individuals exist between D. chacaye and D. articulata, and between D. chacaye and the related Ochetophila trinervis. We tested the hypothesis of hybridization in open forests of northern Patagonia, Argentina. We used neutral markers (nuclear by four polymorphic isozyme loci and maternally inherited trnL/trnF cpDNA intergenic spacer) and morphological features (leaf and reproductive traits) on all presumed parental species and 2 putative hybrids. We also studied flowering phenology, pollinators, and we performed cross-pollination experiments. Isozyme cluster analyses revealed that putative hybrids were closer to D. chacaye. Parental D. chacaye and D. articulata and its hybrid shared the same cpDNA haplotype, while morphologically the hybrid was similar to D. articulata. The hybrid between D. chacaye and O. trinervis had the haplotype of the latter, but was morphologically closer to D. chacaye. Flowering phenology was sequential, O. trinervis flowering latest. D. chacaye had 20 pollinators in common with D. articulata and 10 with O. trinervis. Seeds were obtained when crossing D. articulata pollen with D. chacaye ovules, and D. chacaye pollen with O. trinervis ovules, but only the first ones germinated. Our results confirm intra- and intergeneric hybridization in Rhamnaceae. Evolution at a geographic scale: Spatial variation in natural selection of floral traits in Anarthrophyllum desideratum PAIARO V.* (1); SéRSIC A.N. (1); COCUCCI A.A. (1) and OLIVA G.E. (2) (1) IMBIV (CONICET-UNC) (2) INTA EEA-Santa Cruz *valepaiaro@yahoo.com The strength and direction of natural selection on floral traits can vary spatially because of variation in the biotic and abiotic selective scenarios. In the absence of plasticity, variation in selection among populations should lead to genetically based phenotypic differences in the traits under selection. Previous studies on the Southern Patagonia endemic shrub Anarthrophyllum desideratum have shown significant geographic patterns in floral variation and different pollinator assemblages among conspecific populations. To determine the importance of natural selection on spatial variation of flowers in this species, we measured phenotypic selection on different floral traits (morphometric, color and nectar traits, and floral display) in four distant populations with distinct pollinator assemblages. Flower number, corolla area, petal width and length, style exertion, nectar volume and concentration showed significant patterns of selection. While flower number was positively selected in all sites, the identity of the other floral traits under selection and/or the selection gradients (strength and/or the direction of the selection) varied among populations. Our results showed a geographic mosaic of phenotypic selection, and suggest that natural selection mediated by the abiotic environment and/or pollinators would be at least partly responsible for the evolution of flower variation in natural populations of A. desideratum. Orchid speciation and coexistence explained by above- and belowground mutualisms PAUW A.* (1); WATERMAN R. (2); BIDARTONDO M. (3); SAVOLAINEN V. (2) and BARRACLOUGH T. (2) (1) Stellenbosch University, South Africa (2) Imperial College London (3) Royal Botanic Gardens Kew *apauw@sun.ac.za Most species survive and reproduce only by interacting with other species, and the evolution of biodiversity depends intimately on the evolution of these interactions. Both pollination by animals, and symbiotic relationships with mycorrhizal fungi, are thought to have been important factors in the success of the angiosperms. However, the relative roles of above and below ground mutualisms in plant speciation and coexistence remain obscure. Here we show that shifts in pollination traits are important for speciation in a diverse group of orchids, whereas shifts in fungal partner are important for coexistence but not speciation. Molecular surveys of diversity show that closely related species of orchid differ in pollination mode more than expected by chance, indicating a role of pollination shifts in reproductive isolation and speciation. In contrast, fungal partners are conserved among closely related orchid species, but are significantly partitioned within regional guilds, consistent with their role in reducing competition for nutrients. Therefore, new species arise through adaptation to new pollinator types in different areas, but the assembly of local communities requires use of distinct fungal partners. Our results demonstrate the primacy of pollination in driving speciation, through its direct impact on reproductive isolation, and the importance of fungal partners for coexistence, as expected because of their direct role in nutrient use. Pollinator-mediated isolation and parallel evolution of floral traits in High Andean Schizanthus hookeri and S. grahamii PEREZ F.* and GONZáLEZ A. Pontificia Universidad Católica de Chile *mperezt@bio.puc.cl Plant-pollinator interactions may contribute significantly to reproductive isolation in flowering plants. Here, we asked whether the two nominal species Schizanthus hookeri and S. grahamii, have undergone parallel patterns of diversification in association to their pollinators. These two herbaceous species differ in their pollination syndromes and one of them (S. grahamii) exhibits two geographically separated morphs. We used two cpDNA regions to investigate the genetic affinities between S. hookeri and the two morphs of S. grahamii. We also recorded pollinator visits at two sites where S. hookeri occurs sympatrically with each morph of S. grahamii. Chloroplast DNA data indicate that the two morphs of S. grahamii are not monophyletic, suggesting that they arose independently by parallel evolution. Floral visitors discriminated the flowers of S. hookeri from each morph of S. grahamii in sympatric populations: while only hummingbirds visited both flower morphs of S. grahamii, flowers of S. hookeri were visited primarily by bees. We conclude that the two hummingbird-pollinated morphs of S. grahamii arose independently and that floral traits subjected to parallel evolution have promoted reproductive isolation between sympatric species through selection for different pollen vectors. Acknowledgments: FONDECYT 11085018, FONDAP 1501-0001 to CASEB, Pontificia Universidad Católica de Chile and Millennium Scientific Initiative (Mideplan, Chile) PO2-051-F ICM, and PFB-23 Conicyt. Reappraisal of vegetative morphology and architecture in plant differentiation: the case of South American Nothofagus PUNTIERI J.* (1); STECCONI M. (1); GROSFELD J. (1); BRION C. (1) and BARTHÉLÉMY D. (2) (1) INIBIOMA, Bariloche, Argentina (2) INRA, Umr AMAP, Montpellier, France *jgpuntieri@gmail.com Since early botanical research, the relevance of reproductive morphological traits for species differentiation has been emphasized, with the explicit argument that such traits exhibit little variability. Simultaneously, variability of vegetative morphology following environmental factors has been highlighted. But in recent decades, plant vegetative traits have been used with success in the evaluation of plant form and its mathematical modelling. Here we reassess the role of vegetative-morphological and architectural traits in the differentiation of South American Nothofagus species. For these species, the morphological criteria most frequently used so far have been, almost exclusively, leaf and reproductive traits. A promising use of vegetative morpho-architectural traits for the discrimination of Nothofagus species must start with the identification of: (a) the ontogenetic stages of the species concerned, (b) the structural units making up the individuals (metamers, growth units, annual shoots and axes), (c) the morphogenetic gradients linking the structural units among them and (d) the nature of the reiterations these species develop. Feeding behaviour of southern beeches aphids: testing prediction of coevolution theory of autumn tree colours RAMIREZ C.* and LAVANDERO B. Universidad de Talca *clramirez@utalca.cl The evolutionary explanation for the change in leaf colour during autumn is still debated. Autumn colours could be a signal of defensive commitment towards insects (coevolution) or an adaptation against physical damage because of light at low temperatures photoprotection). The coevolutionary theory states that autumn colours could have evolved in plants to avoid parasites by signalling the defensive commitment of the tree, and predicts that red leaves should be avoided in autumn by aphids, while green leaves should be preferred instead. However, no direct evidence of active rejection of red leaves has been found so far. Here we present results of feeding behaviour of aphids of the genus Neuquenaphis on red and green leaves of southern beeches in Central Chile. Feeding behaviour of sexual females of red and green leaves was electrophysiologically monitored in the laboratory. Abundance of aphids on three southern beeches species during autumn is also presented. Our results suggest that: 1) red leaves are not actively rejected in autumn by aphids, and 2) abundance of aphids on southern beeches species studied varies in a species-specific manner independently of colours. Both results do not support the coevolutionary theory of autumn colours. Phylogeography of Passiflora ovalis (Passifloraceae) RAMOS CAZE A.L.* (1); G. DUTRA C. (1); L. BONATTO S. (2) and B. FREITAS L. (1) (1) Universidade Federal do Rio Grande do Sul (2) Pontifícia Universidade Católica Rio Grande do Sul *analuizacaze@gmail.com Passiflora ovalis Vell ex. Roemer is restricted to the Atlantic Forest habitat of São Paulo, Rio de Janeiro, Espãrito Santo, Bahia, and Pernambuco states in Brazil. Due to its morphological complex, 225 individuals from 12 populations along the species distribution were sampled aiming to establish the species phylogeographic pattern. DNA was extracted and amplified for the intergenic plastid spacer trnS-trnG, and nuclear ITS. Sequences resulted in two alignments and nucleotidic and haplotipic diversity were estimated. Haplotypes were generated, and their phylogenetic relationships determined by a median-joining network. Also, analyses were run to detect geographically homogeneous groups that genetically differ from each other. trnS-trnG analysis showed haplotipic and nucleotidic diversity of 0.6965 (+-0.0119) and 0.0053 (+-0.0030), and resulted in 5 haplotypes. For ITS, 8 sequence types were found, and the nucleotidic and haplotipic diversity were 0.8584 (+- 0.0119) and 0.0112 (+- 0.0059), respectively. The diversities were high, suggesting an ancient evolutionary history. Intra and interspecific genetic variability were high and significative for both markers. Two geographic barriers were detected, one in Bahia (Jequitinhonha river) and one in Espãrito Santo (Doce river), preventing gene flow among populations. The phylogeographic analyses suggest two refugia area in the Atlantic Forest: one in Espãrito Santo, and other in Bahia. Evolutionary history of epiarenic "tillandsiales" in the coastal Atacama and Peruvian Desert SALINAS M.F.*; PéREZ M.F. and MARQUET P.A. Instituto de Ecología y Biodiversidad (IEB) & CASEB, Depto. de Ecología, Pontificia Universidad Católica de Chile *fernandasali@gmail.com The genus Tillandsia (Bromeliaceae), with near to 540 species, is a distinctive canopy element of Neotropical forests. Near half Tillandsia species exhibit extreme epiphytic habit without phytotelmata, roots reduced to holdfasts and foliar trichomes for the acquisition of water and nutrients. In the hyperarid coastal Atacama and Peruvian Desert in South America, eight Tillandsia species exhibit specialized substrate ecology, growing on sand (epiarenic habit) forming extended patches named “tillandsiales” associated to coastal fogs. The objective of this research was to evaluate the evolution of substrate ecology in Tillandsia and its relation with the increase in aridity, testing the hypothesis of secondary acquisition of the epiarenic habit as a consequence of the aridification that resulted in the replacement of Paleocene rainforests by the Atacama and Peruvian Desert. All epiarenic and other 20 Tillandsia species were collected and DNA was extracted from leaves. Sequences of matK chloroplast region of the genome were analyzed with 85 species of Tillandsieae tribe previously sequenced by Barfuss et al. (2005). Results reveal the independent evolution of the epiarenic habit at least three times from the epiphytic habit in Tillandsieae and the relation of the epiarenic habit with the increase in aridity. Aknowledgements: Fondecyt-FONDAP 1501-0001 to CASEB; Iniciativa Cientifica Milenio (Mideplan), P05-002, and grant PFB 23 (CONICYT) to IEB (Chile). Origin, gene pools and domestication events in lima beans ( Phaseolus lunatus l.) from the Americas SERRANO SERRANO M.L.* (1); MOTTA-ALDANA J.R. (2); CHACóN SANCHEZ M.I. (1); CASTILLO-VILLAMIZAR G.A. (2) and DEBOUCK D. (3) (1) Universidad Nacional de Colombia (2) Universidad Industrial de Santander (3) Centro Internacional de Agricultura Tropical CIAT *marlise10@yahoo.com The aim of this research was to assess the genetic structure of wild Phaseolus lunatus L. in the Americas and the domestication events in the species. For this purpose, nuclear and non-coding chloroplast DNA markers were analyzed in a collection of wild and domesticated Lima bean accessions and some allied species. Three highly divergent wild Lima bean gene pools, AI, MI, and MII, with mostly non-overlapping geographic ranges, are proposed. The results support an Andean origin of wild Lima beans and an early divergence of the three gene pools at a time that correlates with the final uplift of the northern Andes during Plio-Pleistocene times. The results support two domestication events for wild Lima beans, one would have occurred at the western side of the Andes in Ecuador and northern Peru from the wild gene pool AI, and the second one would have occurred in Mexico from the wild gene pool MI, in the area to the west and northwest of the Isthmus of Tehuantepec. In both domestication events there was a strong reduction of genetic diversity due to founder effects indicating that wild Lima beans would be useful for future breeding programs. Geographic patterns of morphological variation in Turnera sidoides L. subsp. pinnatifida (Turneraceae) SOLíS NEFFA V.G.* Instituto de Botánica del Nordeste (UNNE-CONICET) *viviana@agr.unne.edu.ar Turnera sidoides is a species suitable to address some questions concerning the evolution at infraspecific level. This complex of perennial rhizomatous herbs has a marked morphological variability and is widely distributed in southern South America. It extends over S Bolivia, Paraguay and Brazil, Uruguay and Argentina, reaching 39ºS. Aiming to contribute to the understanding of the patterns of variation within this species, T. sidoides subsp. pinnatifida was selected to perform a detailed evaluation of the morphological variation along its entire distribution area. The multivariate analysis based on leaf traits and flower colour data allowed the differentiation of five morphotypes. Common-garden experiments also demonstrated that the morphological variants have a strong genetic basis. The morphotypes occur in geographically separated areas with different climatic regime, vegetation cover and soil types. Although, these results are suggestive of adaptive differentiation of subsp. pinnatifida, the intermediate degree of coincidence between morphological and bioclimatic ordinations suggests that the present-day biogeographical patterns of morphotypes are only partially influenced by current climate. Historical events may explain the origin of the five morphotypes, while the current climatic and ecological factors may be contributing to the maintenance of the morphological differentiation and the patterns of distribution of the morphotypes of T. sidoides subsp. pinnatifida. Parasites of marsupials from the Patagonia (Argentina) VEGA R.M.* (1); SAGE R. (2) and BRUGNI N.L. (1) (1) Laboratorio de Parasitología. INIBIOMA - UNCo (2) SNAP *rociovega@crub.uncoma.edu.ar New World marsupials are an important component of mammal communities of South America. Among the Neotropical orders, Microbiotheria is more related to the Australian marsupials. The parasites described for Patagonian marsupials are: Pterygodermatites spinicaudatis, Allasogonoporus dromiciops , and Ixodes neuquenensis in Dromiciops gliroides (Microbiotheria) and Pterygodermatites kozeki in Thylamys pallidior and Lestodelphis halli (Didelphimorphia). Here, we report our parasitological study of these three species of Patagonian marsupials. During a survey of small mammals, 15 specimens of D. gliroides from the Lanín and the Nahuel Huapi National Parks, 4 of T. pallidior from Laguna Blanca National Park, and 1 of L. halli from near Clemente Onelli, were necropsied. Parasites were recovered and population indices were calculated. Within the 3 marsupial species 180 parasites were found. These parasites included: 4 species of Nematoda, 1 of Digenea, and 2 of Acarii for D. gliroides, 3 species of Nematoda for T. pallidior, and 3 species of Nematoda for L. halli. Only specimens of Pterygodermatites spp. were present in the 3 host, with the highest prevalence and medium intensity of infection in D. gliroides and T. pallidior. From the hosts studied 8 out of the 12 parasite species are new records. Dromiciops gliroides does not share parasite species with the other 2 host. These findings support the low phylogenetic affinity between D. gliroides and the remaining Neotropical marsupials. Preliminary analysis of intraspecific variability in Aureliana fasciculata (Vell.) Sendtn. (Solanaceae). ZAMBERLAN P.* (1); FREGONEZI J. (1); BONATTO S. (2); STEHMANN J.R. (3) and FREITAS L. (1) (1) Universidade Federal do Rio Grande do Sul (2) Pontifícia Universidade Católica Rio Grande do Sul (3) Universidade Federal de Minas Gerais *priscilla.zamberlan@gmail.com Aureliana fasciculata is a shrub endemic to the Atlantic Rain Forest. Three varieties are recognized: A.f. var. fasciculata, A.f. var. longifolia, A.f. var. tomentella. Due to great morphological differences, the classification of these varieties as species has been considered. In order to genetically characterize the varieties, 182 individuals were collected along the species distribution. Twenty four of them were chosen to a preliminary analysis through the sequencing of plastidial spacers trnS-trnG and trnH-psbA. Seven haplotypes were obtained and a haplotype network was generated. Nucleotidic (0.0180 +/- 0.0093) and haplotipic (0.8370 +/- 0.0399) diversities were high, indicating great differences among haplotypes (2 haplotypes of var. fasciculata and tomentella were separated by 6 mutational steps). However, analyzing only few individuals along the distribution may have inflated these values. Individuals of var. fasciculata had 5 haplotypes, 2 of them also found in var. tomentella, which did not have any unique haplotype. Individuals of var. longifolia had 2 close and exclusive haplotypes. Our preliminary data indicate that var. longifolia forms one group genetically differentiated within the species, and var. fasciculata and tomentella, which displayed signs of geographical structure, forms another. The taxonomic status of the groups remains uncertain. The ongoing analysis with a broader sample and microsatellite markers will add information to this issue. Conservation Hymenochaetacee (Hymenochaetales, Basidiomycota) in northwest Sao paulo state, Brazil ABRAHãO M.C.* and GUGLIOTTA A.D.M. Instituto de Botânica, São Paulo, Brasil *mairaabrahao@hotmail.com The aphyllophoroid diversity in the northwest São Paulo State is almost unknown. This region is one of the most threatened of São Paulo State and initially covered by Semideciduous Stacional Forest has been replaced by crops, pastures and urban areas. The Hymenochaetaceae taxonomy has been modified with studies of molecular biology, but the taxonomic position of some species is still doubtfull. Its species has resupinate, effused-reflexed, pileate sessile or stipitate, or clavarioid basidioma, usually brown to reddish-brown or yellow-brown context which darkens permanently with KOH and setae usually present in the hymenium. This survey aimed to increase the knowledge of biodiversity and geographical distribution of basidiomycota in São Paulo State and Brazil. Specimens were collected on field trips between March 2007 and May 2008 in ten remnant forest fragments. Material collection, preservation and herborization (deposited in SP and SJRP Herbaria) were made following standard techniques. Identification was based on basidioma micro and macroscopic features. Thirteen species belonging to five genera (Fuscoporia, Hymenochaete, Inonotus, Phellinus and Phylloporia) were found. Inonotus adnatus is new from Brazil, four species are new records for São Paulo State (Fuscoporia rhabarbarina, F. senex, Inonotus xanthoporus and Phylloporia pectinata) and six are newly cited for this region. All species are new citations for the collections localities. (Financial support: FAPESP). Does Pilgerodendron uviferum require catastrophic disturbances to regenerate? BANNISTER J.* and BAUHUS J. Silviculture Institute, University of Freiburg *jan.bannister@waldbau.uni-freiburg.de Pilgerodendron uviferum (D. Don) Florin is an endemic conifer of southern Chile and some areas of Argentina. Although the need of P. uviferum for catastrophic disturbances to regenerate and its intolerance to shade has often been repeated in the literature, it is far from clear. Therefore, this study aimed to analyse regeneration dynamics in undisturbed and disturbed P. uviferum forests on Chiloé Island, North Patagonia. An inventory of trees and regeneration in undisturbed and disturbed swamp forests and upland forests has been made (for 16 stands). Light conditions within stands and for seedlings (%PPFD) were measured based on the one-point overcast sky conditions method. Trees were cored and root collar discs from P. uviferum seedlings were collected. The structure of undisturbed stands indicates that P. uviferum initially colonized the site and was able to continue regenerating on site up to the present. The results of this study show that P. uviferum should not be considered a shade-intolerant species because it can regenerate under the low light conditions of the understorey in old- growth forests. Our results further indicate that seedlings of this species are not very responsive to increased light. For the forests of Chiloé, P. uviferum does not appear to need catastrophic disturbances to regenerate. To the contrary, catastrophic fires may eliminate the species from tracts of the landscape, where no seed trees survive. Seed availability as a barrier to forest recovery in a rural landscape in Chiloé Island, Chile. BUSTAMANTE SáNCHEZ M.A.* (1) and ARMESTO J.J. (2) (1) P. Universidad Católica de Chile (2) Instituto de Ecología y Biodiversidad *mbustama@bio.puc.cl Forest succession on human disturbed lands is often slow. Specifically, forest recovery may depend on the arrival of seeds from nearby forests. In temperate rain forests of Chiloé Island (42 S), most canopy trees are dispersed by birds. We investigated arboreal seed rain in three successional shrub communities with different attractiveness for bird dispersers: a shrubland dominated by a wind-dispersed pioneer, one dominated by a fleshy-fruited pioneer, and one with small-size trees that can act as perches. As the degree of attractiveness to frugivorous birds will increase with the amount of food and/or perch sites, we asked whether differences in seed rain composition and abundance are caused by a differential frequency of avian-frugivore visits. Seed density of animal dispersed seeds will be lower in the community less attractive to frugivores. In contrast, because wind-dispersed seeds show leptokurtic seed shadows, their density will be lower in all communities. Seed rain was monitored during two fruiting seasons (2007-2008) using seed traps. As predicted, significantly higher densities of fleshy-fruited seeds were found below the community with fleshy-fruited shrubs. In contrast, seed density of non-fleshy fruited trees was lower and similar among communities. Our results suggest that seed availability is heterogeneous in this rural landscape, and the type of early successional community and dispersal mode can explain this heterogeneity. Birds as mediators of ecological restoration in woodlands of Northwestern Patagonia, Argentina. CAVALLERO L.*; RAFFAELE E. and AIZEN M. Universidad Nacional del Comahue - INIBIOMA *laucavallero@yahoo.com.ar Northwestern Patagonian woodlands are the communities most affected by fire and firewood extraction. Standing dead trees are used by birds as perching structures in burned areas, increasing seedling recruitment beneath them. In National Parks it is allowed standing dead trees extraction in burned areas and this may limit natural recolonization. In November 2008, 450 seed traps were installed in 3 communities burned in 1999 to evaluate the perch effect of standing dead trees in post-fire recolonization. In each community, 75 seed traps were placed below perches and 75 were placed in clearings. Seed traps were revised three times during summer. Collected samples were analyzed looking for the presence of bird-dispersed seeds. In January 2009, 350 seedlings of B. buxifolia and R. magellanicum were transplanted in a burned community in two microsites: below shrubs and in clearings, to evaluate suitable microsites for seedling’s recruitment and to test if birds drop the seeds in high survival likelihood microsites. Perch effect was significant during the sampling season, 2980 seeds were captured, which 40% were dispersed by birds. Of the bird-dispersed seeds, 84% were found in seed traps placed below perches. Seedling survival was higher below shrubs. These results suggest that birds are good seed dispersers, dropping seeds in microsites where seedling recruitment is high. Therefore, birds develop a key role as mediators of ecological restoration in post-fire communities. Evaluation of environmental and productive functions of North Patagonia wetlands DIEHL P.* (1); CREMONA M.V. (2) and ENRIQUEZ A.S. (1) (1) CONICET (INTA-EEA Bariloche) (2) INTA-EEA Bariloche *pdiehl@bariloche.inta.gov.ar Semi-arid climate of extra-andean Patagonia is reflected on its dominant steppe vegetation. Landscape enables the development of wetlands (mallines), with azonal features related to: hydrology (surface/sub-surface water during all year), soils (high C-nutrients concentration), hydrophilic vegetation (Juncaceae-Cyperaceae) and high forage production. The aim of this work was to quantify characteristic variables of mallines, to contrast them with the periphery and degrades areas. On 4 sites along a W-E precipitation gradient (590-150 annual mm), we quantified: phreatic level at the center, aerial net primary productivity-ANPP (annual harvest n=20 0.2 m2), organic carbon-SOC, total nitrogen-Nt, and available phosphorus-Pa on composite soil samples (n=3). Phreatic depth was 0-10 (late winter), and 60-80 cm (early autumn) compared to nearby steppe (>3m). ANPP ranged between 6800-1900 KgMS/Ha at the gradient extremes vs. 900-400 in the transition to the steppe. SOC between 3-23% show the importance of these ecosystems as C reservoirs. SOC was 83% higher than the periphery, with similar tendency for Nt (84%), but the opposite for Pa, 42 % lower. Intensive grazing degradation reduced ANPP about 60% at gradient extremes as well as C: 14-75%, Nt: 8-33% and Pa: 53-55 %. In some disturbance levels an increase in Pa was observed (22-88%). Results revealed the value of these ecosystems in terms of environmental functions as C and water reservoirs, and mitigation of degradation processes. Drivers of plant and belowground invertebrate community composition on New Zealand gravel beaches: a threatened rare eco FORGIE S.*; ST JOHN M. and WISER S. Landcare Research-Manaaki Whenua *forgies@landcareresearch.co.nz In New Zealand (NZ), the heterogeneity of the landscape has resulted in a diverse array of small, often widely dispersed, rare ecosystems that tend to occur in extreme, typically treeless, environments. During 2006-08 we studied vegetation and invertebrates on gravel beaches distributed along the New Zealand coastline to better understand this naturally rare ecosystem. These systems had never before been studied at a national scale despite being highly threatened by urbanisation, weeds, adjacent agriculture, introduced animals and predicted sea-level rise, and containing both threatened, rare and endemic plants and animals. GIS data and site-level geomorphological, abiotic, vegetative and from surface litter down invertebrate composition data collected from fifty gravel beaches across NZ were examined. Many of these sites were highly modified by exotic plants and animals while some had a significant, and often distinctive, native component. Plant composition varied according to geography, climate, topology, and proximity of both human dwellings and certain native vegetation types. Structure of the invertebrate community was related to many of the same factors as the plant community but most highly to the presence of exotic plants. These findings suggest that exotic plant invasion is not only altering the aboveground community of plants and possibly their consumers, but also impacting the invertebrates that inhabit litter and soil in this rare ecosystem. Mating system and genetic structure of timber species Cariniana estrellensis (Lecythidaceae) in Southeastern Brazil. GUIDUGLI M.C.*; FERES J.M.; CONTEL E.P.B.; MESTRINER M.A. and ALZATE-MARIN A.L. University of São Paulo (USP) *rocks_bio@yahoo.com.br Cariniana estrellensis (Raddi) Kuntze (jequitibá-branco) is a wide-ranging tropical tree species occurring in Brazil, Bolivia, Paraguay and Peru. Due to the high deforestation rates in its native range, C. estrellensis is considered an endangered species. We investigated the genetic structure and mating patterns of the last 30 adult-trees of C. estrellensis from an 8.0 ha forest fragment in Southeastern Brazil. By using 9 microsatellite loci the genotypes were determined for all the 30 adult-trees and 399 offspring originated from 7 open-pollinated families. A weak but significant spatial genetic structure among adult-trees was detected up to 387 m. No significant inbreeding coefficient was detected in both generations. Mating system analysis showed that the studied population is perfectly outcrossed (tm=1.005), and probably self-incompatible. Nevertheless, small deviations from random mating were detected for correlated matings (rp=0.195), indicating that part of the offspring are full-sibs. The variance effective population size was of 3.18, revealing that for ex situ conservation, seeds should be gathered from all 30 adult-trees from fragment, in order to keep an effective population size of 100. However, open-pollinated seeds from all the plants could not be gathered, since asynchrony flowering time for this species was also observed. These results provide a blueprint to guide the conservation management policies for this species. Financial Support: FAPESP, CNPq and CAPES. Effects of stockfencing and invasive mammal pests on biodiversity conservation in lowland New Zealand KING C.* (1); BARKER G. (2); BURNS B. (3); DIDHAM R. (4) and INNES J. (2) (1) University of Waikato, Hamilton (2) LandcareResearch, Hamilton (3) University of Auckland (4) University of Canterbury, Christchurch *c.king@waikato.ac.nz Forest health was measured during summer and autumn 2008 in 53 fragments (mean 5.3 ha) of formerly extensive indigenous forest in rural landscapes of Waikato, lowland North Island. Litter-dwelling invertebrate detritivores were up to 100 times more abundant in fragments fenced for 30-40 years compared with unfenced fragments. A key introduced pest (the European ship rat Rattus rattus) is abundant throughout the region. Rats in summer reached higher densities in 4 fenced (mean 6.5 rats/ha) than in 4 unfenced, grazed fragments (mean 0.5 rats/ha: p=0.02). All 8 fragments were cleared of rats in January-April 2008, but were reinvaded within a month, whether isolated from an adjacent source of immigrants or not (p= 0.25, 0.67). Our results identify a previously unsuspected dilemma for conservation in forest fragments. Stock fencing improves plant regeneration, litter decomposition and invertebrate populations, but if used alone it also encourages high numbers of ship rats and other pests, which destroy seeds, invertebrates and nesting birds. Maximising the biodiversity values of forest fragments therefore requires both fencing and control of ship rats. Population size and reprodictive biology of the rare species Banksia nivea subsp. uliginosa LADD P.* (1); THAVORNKANLAPACHII R. (1) and BYRNE M. (2) (1) Murdoch University (2) Department of the Environment. Western Australia *P.Ladd@murdoch.edu.au Banksia nivea spp. uliginosa is one of many Declared Rare species found in a community that is also is rare due to extensive fragmentation from agriculture and land clearing. The aim of this project was to determine the pattern of pollen dispersal and reproductive biology of the species. The study investigated the effectiveness of pollen dispersal both within and between populations, the relationship between population size and reproductive biology, and any influences of isolation on gene flow and reproductive biology. There was no significant relationship between seed set and population size. The species exhibits a predominantly mixed mating system with high outcrossing rate (tm≈ 0.95) and low level of selfing. There was no significant genetic difference in the gene flow study populations but differences in population structure such as size, shape, and density may have led to increased biparental inbreeding and higher correlated paternity. High levels of predation limited the production of viable seeds and destroyed up to 54% of seed in an infructescence. Germination success was generally high (93.4%) in all population. Fire could have a large impact on the population persistence. Large (ie., old) unburnt plants can hold a large seedbank (possible more than 10 years of seeds) so re-establishment after a fire in a long unburnt population should be prolific. Further studies on pollinators, seed predation, and the species’ time to maturity and response to fire are recommended. Size and spatio-temporal variations of the largest known Andean condor population: communal roosts and conservation LAMBERTUCCI S.* Laboratorio Ecotono, Universidad Nacional del Comahue-INIBIOMA/CONICET *slambertucci@gmail.com Estimations of population sizes of endangered species are fundamental for conservation. The current estimate of the global Andean condor Vultur gryphus population comes from limited local scale counts. Simultaneous censuses on 10 condor communal roosts were conducted (between 2006-2008) in northwest Patagonia, Argentina, to obtain a minimum population number, to estimate the size of the local population, and to describe bird use of the roosts by season and age classes. I fitted the data to two asymptotic models to calculate the population of condors as a function of the number of communal roosts surveyed. In an area of approximately 6300km2 I obtained a minimum population size of 246 individuals by direct observation, and a population estimate of 296 condors (range 260-332) by applying the models. This value represented the largest population known for this species, comprising 68.5% adults and 31.5% immatures. Condors had large aggregations in some communal roosts and used the study area with a clear seasonality, increasing from autumn to spring and decreasing in summer. Long-term monitoring of communal roosts along the Andean condor’s distribution can be useful for the detection of potential declines of this rare and vulnerable species. Ground-active beetles as indicators of biodiversity conservation in Tierra del Fuego National Park. LENCINAS M.V.* (1); MARTíNEZ PASTUR G. (1); SOLER ESTEBAN R. (1); CóRDOBA J. (2) and SALAZAR G. (2) (1) CADIC - CONICET (2) UNLP *vlencinas@gmx.net Patagonian insect diversity is mostly endemic and includes relevant relictual species. Tierra del Fuego National Park (TDFNP) is the only one National Park which protects natural ecosystems in the Island. However, the biodiversity status remains unknown to evaluate their effectiveness. The aim was to analyze the conservation effectiveness of the southern area of TDFNP compared to environmental types outside the park, through the study of the ground-active beetles (GAB) as indicators. 120 pitfall set traps were placed in forested and non-forested environment types. Data were analyzed with NMS, PERMANOVA and PERMDISP. 82 GAB morphospecies were identified, which 12% was only collected inside TDFNP, 46% only outside and 42% was shared. Ordination analyses showed differences between inside-outside TDFNP GAB assemblages and among environment types. Particularly, significant differences were detected for centroid position (F=7.09, p=<0.01) and dispersion (F=15.14, p=<0.01) of Nothofagus pumilio forest groups. However, N. betuloides forests (F=1.28, p=0.198 and F=0.14, p=0.714) and peat-lands (F=0.75, p=0.751 and F=1.11, p=0.319) did not present differences between inside-outside TDFNP. Southern area of TDFNP conserve mostly of the observed GAB diversity of N. betuloides and peat-lands. However, some environment types (e.g. N. antarctica and grasslands) are heterogeneous along the Island, as well as N. pumilio forests, which only partial diversity are included in the studied area. Invasion success of European bumblebees in SW South America - Similarities and differences with Oceania and conservation. MORALES C.L.* and AIZEN M.A. INIBIOMA (UNCOMA-CONICET) *cmorales@crub.uncoma.edu.ar European bumblebees Bombus ruderatus and B. terrestris invaded NW Patagonia (Argentina) after their introduction in Chile for crop pollination. Since 2000, I recorded the flower species visited by both invasive species, and by the native congener Bombus dahlbomii. I explored the use of floral resources by the three bumblebee species. Both alien bumblebees thrived in disturbed and undisturbed habitats, whereas the native bumblebee tended to be more associated to undisturbed habitats. The short-tongued B. terretris was highly generalist, visiting both native and alien flowering species, resembling the distribution and floral use by this species in invaded areas of Tasmania and New Zealand (NZ). The long-tongued B. ruderatus was more specialist than B. terrestris, as reported for NZ. However, in Argentina B. ruderatus foraged on many native species, which contrasts with the exclusive exploitation of floral resources from alien species in NZ. This difference might relate to the availability of a diverse native assemblage of typical “bumblebee- flowers”. These flowers with long corollas and concealed nectar were pollinated by the long-tongued B. dahlbomii. The interplay between different evolutionary trajectories, resulting in disparate morphological flower-pollinator constrains, and habitat disturbance might influence the invasion success of introduced pollinators. Understanding all these factors can increase our ability to predict the impact of bumblebee introductions. The decline and restoration of Sheoak Grassy Woodlands on Eyre Peninsula, South Australia. PEETERS P.* (1); GERSCHWITZ T. (2); BELL C. (2) and CARPENTER R. (3) (1) Dept. of Environment and Resource Management, Queensland (2) Dept. for Environment and Heritage, South Australi (3) University of Adelaide, South Australia *petaurus@ozemail.com.au Sheoak Grassy Woodland (SGW), dominated by the highly palatable, N-fixing tree Allocasuarina verticillata (Casuarinaceae), was widespread on Eyre Peninsula, South Australia, at the time of European settlement, but is now a threatened ecological community. Its decline probably contributed to the local extinction of several animal species. Our objective was to identify threats to SGW, in the context of an ecological model, and determine its restoration potential via monitoring and adaptive management. Threats include high grazing pressure, and shrub invasion by Leucopogon parviflorus (Ericaceae). Reinstatement of certain fire regimes and moderate grazing pressure may be needed to restore and maintain this community. Restoration efforts in Coffin Bay National Park in the last 9 years have included closure of watering points, herbivore control and revegetation. Browsing damage to sheoaks appears to be lower in areas with high herbivore control compared to medium or low herbivore control, and native grasses are recovering. However, past degradation (including soil erosion, high stocking rates, vegetation clearing, cessation of indigenous hunting and burning practices, and the local extinction of the dingo (Canis lupus dingo) may mean that restoration to a pre-European state is unachievable. Ongoing adaptive management will enable managers to define and work towards an ecological state for SGW that will deliver the best results for biodiversity in the short and long term. Diversity of the understory of lenga (Nothofagus pumilio), based on indicators of livestock use, in Chubut (Argentina) QUINTEROS C.P.* (1); GOBBI M.E. (2) and BAVA J.O. (3) (1) Centro de Investigación y Extensión Forestal Andino Patagónico (CIEFAP) (2) CRUB-Universidad del Comahue (3) Centro de Investigación y Extensión Forestal Andin *pquinteros@ciefap.org.ar The forests of lenga are of great ecological value. This are exposed to cattle grazing, this disturbance modify the understory characterized by lenga native and low coverage and low species richness and diversity. The understory is a vital component because it is the basis of food chains regulating ecosystem functions. This paper examines the species composition and diversity of understory lenga, based on the indicators: distance to the wetland, feces and trails. The understory survey was conducted in 51 plots in three sites located in nine transects that began at the edge of a concentration area of livestock (wetland) in the forest. The plots were located at increasing distance from the wetland. We calculated the species richness (r) and diversity indices of Shannon-Weaver (H), Simpson (D) and Equity (E). Using a Principal Component Analysis assessed the relationship between indicators and the understory. The biplot showed variations in the understory: r and D and exotic herbaceous species were associated with increased number of feces and less distance to wetland, H and E together with native species, including the regeneration of Lenga, associated with fewer faces and greater distance from the wetland. The trails were not showed variations. The livestock use in lenga forests promoted increased richness of exotic species. Herbivore have important impacts on this component of the forest ecosystem affects the diversity conservation. Soil conservation in Polylepis mountain forests of Central Argentina: Is livestock reducing our natural capital? RENISON D.* (1); TORRES R. (1); LATORRE N. (2); CINGOLANI A.M. (1) and MARCORA, PAULA G.M.A. (1) (1) Universidad Nacional de Córdoba-CONICET (2) Universidad Nacional de Córdoba *darenison@yahoo.com.ar Mountain forests and their soils provide ecological services such as maintenance of biodiversity, provision of clean water and forage for livestock rearing, one of the main economic activities in mountain areas. However, surprisingly little is known about livestock impact in South American mountain forest soils. To understand how livestock influence patterns of forest cover, soil compaction, soil loss and soil chemical properties, we analyzed these parameters in 100 Polylepis australis woodland plots situated in the subtropical mountains of Central Argentina. We used distance from the nearest ranch as an index of historical livestock impact; we also included a site with a 10 year forest restoration program. Tree seedling presence was evaluated in 285 1 m2 subplots. Our main results reveal that distance from ranch in all cases partly explains tree canopy cover, soil loss, soil compaction and soil chemical properties; suggesting a strong negative effect of livestock – with topography also explaining some of the variance. The valley with 10 year livestock exclusion and re-forestation, showed reduced soil erosion and superficial soil compaction (but not below 5 cm). Plots with Polylepis seedlings were found in sites with less erosion than plots without seedlings, even after controlling for distance to seeder tree and other relevant variables. We conclude that livestock has had a substantial influence on forest soil degradation in the Mountains of Central Argentina. Use of guanacos (Lama guanicoe) as an alternative for linking species and arid land conservation with rural development. SCHROEDER N.* (1); LICHTENSTEIN G. (2); OVEJERO R. (3); TARABORELLI P. (3); MORENO P. (3); GREGORIO P. (4); BOLGERI M.J. (5) and CARMANCHAHI P. (4) (1) IADIZA-CCT Mendoza. Argentina (2) INAPL- CONICET. Buenos Aires. Argentina (3) GIEFAS. AUSMA-INIBIOMA. UNComa. Neuquén. Argentina (4) Grupo de Investigación en Ecofisiología de Fauna Silvestre (GIEFAS), AUSMA-INIBIOMA – CONICET – UNComa. Neuquén, Argentina (5) Wildlife Conservation Society (WCS) *natalias@mendoza-conicet.gov.ar Conflicts between wildlife and human needs are threats to ecosystems in large parts of the world. Successful wildlife management could contribute to solve these conflicts as it promotes conservation of the resource and its environment while generating local income. Based on this concept, and considering the high commercial value of guanaco fiber in the international market, methodologies for capture, shearing and release of wild guanacos have been developed in several provinces in Argentina. Given that experiences started in the late 1990s, there is still little information on the consequences of this activity in the short, medium and long term, at both individual and population level, and about its socioeconomic impact. In this study we analyze biological and social impacts of using guanacos as a strategy for species and arid land conservation and rural development. We based on experiences by a cooperative of fiscal producers from the south of Mendoza and by a sheep producer in a private ranch in Río Negro. Data consists of ecophysiological and social indicators obtained through qualitative and quantitative methods. Results suggest that use of guanacos under high standards of animal welfare could be a production alternative for arid areas, linking conservation with local socioeconomic development. Implementation of alternatives like this could be an opportunity for social groups to face future changes through the construction of new ways of interacting with the ecosystems. Alien plant species along altitudinal gradients in North-Western Patagonia. SPEZIALE K.L.*; WERENKRAUT V. and EZCURRA C. INIBIOMA-Universidad Nacional del Comahue *kspeziale@crub.uncoma.edu.ar Alien plant invasion had not historically affected high elevations but is currently reaching mountain tops. We analyzed the pattern of alien plants species richness along an altitudinal gradient, its association to environmental variables and described basic characteristics of alien species and composition along the gradient. Within Nahuel Huapi national park in northwestern Patagonia we climbed 5 mountains setting 100m2 plots every 100 m of elevation from bottom to top (range 800-2000 m.a.s.l.). In each plot we recorded every vascular plant species, habitat type, collected soil samples and mounted a temperature and humidity sensor. Most of the alien species were original from Eurasia and are regular invaders elsewhere. Many species were recorded at lower elevations than what is found for other areas of Argentina and some others at higher elevations than previously found. Clearly alien species richness decreased from bottom to top of the mountains. GLM analyses showed a positive association to native species richness and shrubland habitats, but a negative one to shrub cover and altitude. Lowland diverse habitats support more alien species than mountain tops of north-western Patagonia, which are not yet severely threatened by alien plants invasions yet. This is probably attributably to the lack of propagules given that several species were already recorded at higher altitudes. Given the current increase in mountain outdoor activities precautionary management is required to prevent future invasions. Seed viability, germination and dormancy of two exotic rose species invasive in the temperate forest of Patagonia, Argentina. SVRIZ M.* (1); DAMASCOS M. (2) and HENSEN I. (3) (1) CRUB- Universisdad Nacional del Comahue- CONICET (2) CRUB- Universisdad Nacional del Comahue (3) Institute of Geobotany and Botanical Garden, Marti *mayasvriz@crub.uncoma.edu.ar We studied seed viability, longevity, bank persistence and germination in Rosa rubiginosa (Rr) and Rosa canina (Rc), two European species invasive in Patagonia. We evaluated the initial and final viability of seed samples collected per year (between 2002 and 2006) in each one of five plants through flotation and tetrazolim tests. Multifilament bags containing viable seeds were buried in the field at 5cm depth. Seed germination was tested every three months, during 15 months. Afterwards, the percentage of ungerminated viable seeds (UVS) remaining in the soil was determined. Initial viability of Rr seeds collected in 1995 was also analyzed. Mean initial seed viability was 56-99% for Rr and 88-96% for Rc. Mean seed germination at spring (maximum values) varied between 26-51% in Rr and 14-45% in Rc. UVS values were 17- 47% and 23-79% for Rr and Rc, respectively. The initial seed viability, germination and UVS percentages differed among years and species. Rr seeds kept their viability after 11 years of dry storage. Seeds of both exotic shrubs lost dormancy after nine months in soil and then germinated. In midsummer a variable percentage of rose seeds enter in secondary dormancy. High seed viability, longevity and persistence in secondary seed bank allow seedling survival and successful colonization. Exotic vs. native species dominance over 20 years of modern plant succession on set-aside farmland TOGNETTI P.M.*; CHANETON E.J.; OMACINI M.; TREBINO H. and LEóN R.J.C. IFEVA, Facultad de Agronomía (UBA) *tognetti@ifeva.edu.ar Invasive exotic plants are major constituents of species pools in modern landscapes. Thus, managing succession requires an understanding of novel trajectories in mixed, native/exotic plant assemblages. We examined trends in native and exotic species abundance over 20 years of spontaneous succession on set-aside farmland in the Inland Pampa, Argentina. Changes in plant cover and species richness were monitored annually on eight permanent plots established in different years (1978–1989). Both native and exotic species occupied early, mid and late successional niches, and exhibited similar life-form replacement patterns, from annual forbs, through annual to perennial grasses. Exotic plant richness declined with plot age, and a few exotic grasses remained dominant through succession. While native perennial grasses slowly increased in richness, only underwent transient abundance peaks. Cluster analysis allowed us to identify alternative community states connected by a network of successional pathways. The system’s dynamics comprised directional trajectories, non-directional loops, and arrested community states dominated by exotic grasses. Our results illustrate the overwhelming role of exotic species in modern succession, and their potential to hinder restoration of native communities on agricultural land. Meeting conservation goals through restoration may require large subsidies, including exotic plant removals and native grass seeding under prescribed disturbance regimes. Communities of parasitoids in native rainforests of southern Chile: experimental approach. UGARTE-LAVADOS Y. (1); OYARZUN C.* (2) and LANFRANCO D. (3) (1) Instituto de Geociencias, PhD Student (2) Instituto de Geociencias, Universidad Austral (3) Instituto de Silvicultura, Universidad Austral *yuriugartelavados@gmail.com Objetives: We investigated changes in the communities of superfamilies Ichneumonoidea and Vespoidea (Hymenoptera) in old-growth and second-growth the native forests “Chilean winter rainfall- Valdivian Forests”. We evaluated both managed and unmanaged forest. Methods:From November 2007 to May 2008, hymenopterans (Hymenoptera: Apocrita) were qualitatively sampled using one malaise trap on the ground in each of four different forest treatments, totalizing 720 h month-1 trapping. We compared the abundance of hymenopterans by calculating a chi-square test (6 months x 2 forest treatments), testing the hypothesis that total abundance was the same for each of two set of forested catchments. Results: The abundance of hymenopterans was significantly higher in managed than reference forest in both contrasting catchments (deciduous, X2 967;2 = 1197, df = 6, P < 0.0001; evergreen, X2 967;2 = 4117, df = 6, P < 0.0001) over the study period. Conclusions: After management, the micro-environments influence insect communities in the understory of forests. Additionally, the abundance and species richness of wasps are higher in disturbed forest sites which had more light and cover of understory plants. Adults of all the wasps presumably feed on floral and extra-floral nectar. Vegetative rich environments in the forest understory could provide more food resources, both of prey and nectar, for the wasps. Characterization and restoration of lenga sites disturbed by fires in two areas of Patagonia, Argentina: first results. URRETAVIZCAYA M.F.* (1); MONELOS L. (2); OYHARCABAL M.F. (3); PERI P. (4) and DEFOSSE G. (5) (1) Fundación para DFAEP-CIEFAP-UNPSJB (2) UNPA (3) CIEFAP-UNPSJB (4) INTA-UNPA-CONICET (5) CIEFAP-UNPSJB-CONICET *mfurretavizcaya@ciefap.org.ar This study was aimed at characterizing vegetation present in two distant and temporally different fire-disturbed lenga (Nothofagus pumilio (Poepp. et Endl.) Krasser)) stands, and to test lenga establishment through plantation experiments in Patagonia Argentina. Study sites are located 1020km apart, in Esquel, Chubut province and Río Turbio, Santa Cruz province. A year after the fire, Esquel site showed 54.8% of the ground covered by 21 species. At Río Turbio, 27 yr after fire, vegetation cover 99.5% of the ground. Only two genera were present in either sites, and neither showed lenga regeneration. Similar lenga seedlings (plug+1), grown in an Esquel nursery, were planted in both sites in fall 2009, protected by polypropylene tree-shelters and metal sheets in Esquel, and plastic material in Río Turbio. Starts growing were monitored in early October in Rio Turbio, and by mid November in Esquel. Of the seedlings planted in Esquel, 85% of shelter protected plants showed initiation of bud break and 63% those with metal sheet. In Río Turbio, only 13% of the seedlings start growing. Preliminary results suggest that tree-shelters in Esquel improved micro-environmental conditions for lenga bud break as related to metal sheet. Differences between sites could be related to plant transport, site environmental conditions and /or time of monitoring. The results of this project will provide useful information for restoration of degraded lenga forests of Chubut and Santa Cruz provinces. Ecology Early nutrition of Nothofagus nervosa in a nursery experiment in NW Patagonia AGüERO M.* (1); MAZZARINO M.J. (1); PUNTIERI J. (1); SATTI P. (1); GROSFELD J. (1); KOWALJOW E. (1); STECCONI M. (2) and CREGO P. (2) (1) U.N. Comahue, CONICET; Quintral 1250, 8400 Bariloche, Argentina (2) U.N. Comahue, CONICET; Quintral 1250, 8400 Bariloc *suelos@crub.uncoma.edu.ar With the objective of analysing the early nutrition of seedlings of native Patagonian trees, an experiment was carried out on Nothofagus nervosa seedlings growing in a nursery. Based on previous results on mature forests, we assumed that nitrogen is the limiting factor for this species (phosphorous was found not to be limiting). Plants were grown on young volcanic soils taken from N. nervosa forests with minimal disturbance, and fertilized (after one year without fertilization) with 100, 200 and 400 g N kg-1 soil, with or without a single rate of P (60 g kg-1), and compared with unfertilized (control) seedlings. Twelve months after fertilization, seedlings under intermediate N rates and P (200 N + 60 P) reached higher stem diameter, length, number of leaves and root diameter than control seedlings. Above-ground and below-ground biomass and N concentration in green leaves followed trends similar to those of the other variables, although differences among treatments were not significant for biomass and N concentration. These results suggest that, unlike our previous ideas, P might be playing an important role in the early nutrition of N. nervosa seedlings. Nothofagus dombeyi and Austrocedrus chilensis establishment in declining forests AMOROSO M. (1) and SUAREZ M.L.* (2) (1) Department of Forest Resources Management, Univers (2) IANIGLA - CCT Mendoza *marialau.suarez@gmail.com In mixed Nothofagus dombeyi-Austrocedrus chilensis forests successful establishment of both species occurs as a consequence of large natural disturbance; however little is known about regeneration of these species at the eastern drier limit where the mortality process in A. chilensis forests known as ‘‘mal del ciprés” generates conditions for new recruitment. The objective of this study was to examine the population dynamics of both species in these conditions. We sampled and described the structure of 6 symptomatic stands and used dendrochronological techniques to reconstruct basal area development and regeneration establishment over time. Bivariate event analysis was performed to examine the temporal relationships between mortality, climate and forest establishment patterns. While the diameter class distributions show similar ranges of sizes for both species, basal area development over time indicates that N. dombeyi established gradually after most the A. chilensis trees did. Likewise, we observed that the recruitment of new individuals over the past 2 decades correspond primarily to N. dombeyi individuals. The result of this study shows that N. dombeyi has the ability for establishing in pure A. chilensis forests resulting in mixed unevenaged forests. Although there is not enough evidence at the moment to indicate a replacement of one species by the other, it is clear that after 100 years since establishment there is an important shift in the composition of these stands. Understanding selective pressures on trichome distribution in Nothofagus pumilio (lenga) along multiple gradients ARBETMAN M.*; MATHIASEN P. and PREMOLI A.C. Universidad Nacional del Comahue-INIBIOMA *marbetman@gmail.com Variable conditions along physical gradients influence patterns of genetic differentiation in trees. Patagonia is characterized by sharp gradients in temperature and humidity that are inhabited by Nothofagus pumilio. We evaluate the presence of trichomes to understand adaptive-plastic responses. Such trichomes are diagnostic features of N. pumilio leaves and their presence and function has not been established yet. Locally, we analyzed the effect of contrasting altitudes, recording the presence of trichomes at seedlings of a reciprocal transplant experiment. Regionally, we quantified the frequency of trichomes along the whole range of the species in about 10 individuals at each of 88 populations. Chi-square test shows statistical differences in the frequency of individuals presenting hairs at populations growing in high vs low elevations. After the reciprocal transplant those differences persist. Multiple regression analysis at the regional scale showed a significant increase of the presence of trichomes with latitude. Populations south of 43ºS were homogeneous and most of them consisted of individuals with trichomes while in the north populations were heterogeneous and eastern populations either lack or yielded less proportion of individuals with hairs. Experimental results show that the presence of trichomes in N. pumilio is fixed genetically and that the distribution along the range is not random and could be related to wettability and/or herbivory pressure. Disarmed trees gain in reproduction ASCHERO V.*; CHACOFF N. and MARTíN S. IADIZA-CCT, Mendoza *vaschero@mendoza-conicet.gov.ar Spine length can act as an inducible defense in plants, because spine length tends to increase with increasing herbivore pressure. Thus, the lower investment in spine production in herbivore-free plants could mean more resources available for reproduction. We hypothesized that 37 years of large herbivore exclusion at a reserve had an effect in the relaxation of mechanic defenses and consequently in tree reproduction. We expect the length of spines would be shorter and the fruit production higher in trees inside the reserve than trees in cattle ranches. Our study area was located in and around Nacuñán Reserve, in the Central Monte Desert of Argentina. We measured spine length in new branches and the total number of fruits per tree in 15 P. flexuosa individuals at 3 pairs of sites inside and outside the reserve. Spines were shorter (ANOVA: F=12.8 , p<0.05) and fruit production was higher (Poisson generalized linear model: z=21.1, p<0.001) in trees inside the reserve than in trees in cattle ranches. We described the decrease in fruit production with spine length with a negative exponential model fitted by a negative binomial generalized linear model: fruits=376*e^(-0.0097*spine length (mm)). Our study suggests that P. flexuosa trees under almost four decades of large herbivore exclusion are less spiny and have greater fruit production than their cattle browsed neighbors. Water transport and vascular architecture of the non-vascular plant Dendroligotrichum dendroides (Polytrichaceae, Musci) ATALA C.* and HERMOSILLA E. DPTO. FORESTAL, U. de CONCEPCION, LOS ANGELES *CATALA@UDEC.CL Mosses are primitive non-vascular plants often few centimeters in height. Nevertheless, mosses belonging to Polytrichaceae have a central strand of specialized cells (hydroids) that transport water. These hydroids are analogous to tracheary elements of vascular plants. The xylem of vascular plants has been found to follow Murray’s law when vessels have no mechanical function. This law predicts optimal water transport per vascular biomass when the sum of the radii to the third power is conserved across branching levels. No such studies have been done in bryophytes with central strand. Dendrologotrichum dendroides (Brid. ex Hedw.) Broth. is a Polytrichaceae from Chile that can grow up to 60 cm. Here we test for Murray’s law and measure actual water conductance in the stems of D. dendroides. The hydroids of this moss depart from Murray’s law suggesting mechanical constrains. The specific water conductance of D. dendroides is higher than in many conifers. Our results suggest that this non-vascular plant can achieve very high water transport rates per stem area that could be important in reaching high plant sizes. More studies should be conducted to unveil the functional and evolutionary significance of the central strand of Polytrichaceae species. Acknowledgments: Tim J. Brodribb. Impact of rooting by feral pigs in native communities of northwestern Patagonia BARRIOS GARCIA M.N. (1); SIMBERLOFF D. (1) and RELVA M.A.* (2) (1) University of Tennessee (2) Laboratorio Ecotono, INIBIOMA, UNCo, CONICET *mbarrios@utk.edu Feral pigs (Sus scrofa) have been introduced to all continents except Antarctica and are one of the world's worst pests. In order to feed on belowground plant parts, fungi, and invertebrates, feral pigs overturn extensive areas of vegetation. This physical disturbance not only directly affects above- and belowground components of ecosystems but also indirectly contributes to plant invasion. The objective of this study was to evaluate the impact of rooting activity in three plant communities (Nothofagus dombeyi forests, Austrocedrus chilensis forests, and shrublands) in northwestern Patagonia using transect surveys and a exclosure experiment. We found similar occurrence, extension and depth of rooting activity across communities, with 35% of the surveyed plots showing some activity by feral pigs, and rooted patch size was on average 0.9 m2 and 5.1 cm deep. Also, plots with 20 to 40% understory cover were more likely to be disturbed. Finally, the exclosure experiment showed that rooting activity significantly reduced herb cover in Nothofagus dombeyi forest and grass cover in shrublands with a concomitant increase in bare ground. These results suggest that all the surveyed plant communities are similarly threatened by feral pig rooting activity and that pigs are significantly changing native plant communities' composition and structure. Exotic species spread after fire in a forest of Nothofagus dombeyi and Austrocedrus chilensis in Patagonia, Argentina BLACKHALL M.* (1); RAFFAELE E. (1) and VEBLEN T.T. (2) (1) Lab. Ecotono, CRUB-UNComa, INIBIOMA (2) Dep. of Geography, Univ. of Colorado, Boulder, USA *meliblackhall@gmail.com Species invasions are often associated with disturbance events. In northwest Patagonia, two of the most important disturbances are fire and introduced herbivores. In 1999 a severe wildfire affected a Nothofagus dombeyi and Austrocedrus chilensis forest, where introduced cattle graze freely. Seven years after the fire we determined the cover of exotic and native forbs in the burned site (inside and outside cattle exclosures) and in an adjacent unburned site. Cover of native forbs was significantly higher than exotic forbs at the unburned site. At the burned site the cover of exotic forbs was higher than native forbs, but no differences were found between plots with and without cattle. Exotic species account for 76.2% of the total cover of forbs at the burned site. Of the total exotic forb cover, 83.6% belongs to species with aerial structures that lose their structure and dieback during the late summer months of highest fire risk. Thus, burning alone favors the spread of exotic forbs and the presence of dry fine fuels, but cattle did not significantly affect the abundance of exotic forbs in the burned or unburnt forest. Variation in endocrine activity in relation to the reproductive cycles of viviparous lizards Phymaturus from Argentina BORETTO J.M.* (1); JAHN G.A. (2); FORNéS M.W. (3) and IBARGüENGOYTíA N.R. (1) (1) INIBIOMA-CONICET-Universidad Nacional del Comahue (2) LARLAC-IMBECU. CC 855, 5500. Mendoza, Argentina (3) LIAM-IHEM-UNCuyo-CCT, Mendoza - CONICET *jorbore@yahoo.com.ar The harsh habitats of Phymaturus lizards in the Andean Highlands and the Patagonian Steppe of Argentina, together with the inability of viviparous to perform vitellogenesis during pregnancy, constrain reproductive cycles. Herein we report the first study of endocrine responses linked to differences in reproduction in P. antofagastensis, P. punae, P. cf. palluma, P. zapalensis, and P. tenebrosus. Hormone assays and ultrastructural studies were used to determine serum estrogen and progesterone in females, serum testosterone in males, and the steroidogenic activity of tubular and interstitial compartments of testes. Females showed interspecific differences in hormone cycles, and males showed interspecific differences to coordinate with female cycles. Testosterone peaks indicate that mating occurs in spring in P. zapalensis, and in mid to late summer in P. antofagastensis and P. punae, respectively. Males of P. cf. palluma with high testosterone were captured throughout the active season. Morphological features characteristic of steroidogenic activity during the spermatogenic cycle were observed in Leydig and Sertoli cells, and evidence of temporal asynchrony in steroid synthesis between testicular compartments were found in all species, especially in P. antofagastensis. Temporal separation of steroidogenic activity appears to propitiate the synchronization of male and female cycles, and the adjustment of reproductive activity to the physiological and environmental constraints. Desertification in North Patagonia: slow variables and rapid processes EASDALE M.* (2); BRAN D. (1); LOPEZ D. (1); HUERTA G. (2) and GAITAN J. (1) (1) Area de Investigación en Recursos Naturales INTA EEA Bariloche, CC. 277 (8400) Bariloche, Argentina (2) Grupo de Sistemas de Producción, Economía y Sociología Rural. INTA EEA Bariloche, CC. 277 (8400) Bariloche, Argentina *measdale@bariloche.inta.gov.ar Desertification defined as land degradation in drylands (UNCCD) is recognised as one of the major threats to global environment, and affects SC countries. Reynolds et al. (2007) using scientific information from diverse disciplines, proposed 5 significant principles as a Dryland Development Paradigm. Our objective was to apply some of these principles to interpret historical and recent desertification processes. Desertification in Patagonian has been widely reported. In Río Negro Province, historical data suggested that land degradation occurred mainly during an initial and short period, when sheep production was rapidly expanding after the national incorporation of this territory (1883). In 1908 there were 4.700.000 sheep (doubling current stock) and land degradation was early reported in 1914, following a drought period. Nowadays the East of Río Negro, area that showed the lowest degree of desertification in an assessment carried on in 1991-94, is involved in a severe desertificaction process. Diverse events that occurred during the last 5-8 years (wildfires, intensification of livestock, and expansion of agriculture frontier), combined with 3 years of droughts, drives the area into a dramatic environmental and productive situation. Regarding these two processes, we want to highlight some common factors: 1) changes surprisingly occurring during short periods 2) climate variability having an active role; and 3) remote global markets promoting rapid changes in land use. Seed Bank dynamics and demography of the exotic species Eschscholtzia californica across altitudinal gradients PEñA-GóMEZ F.* and BUSTAMANTE R. Faculty of Science, Department of Ecological Sciences, Institute of Ecology and Biodiversity, University of Chile. *lofhus@gmail.com The elucidation of pattern and process that occur during seed stage is central to forecast the population fate of plants faced to environmental constraints. Altitudinal gradients constitute appropriate scenarios to assess the demographic constraints of exotic plants during spread. We examined seed bank dynamic of Eschscholzia californica, across an altitudinal gradient in Andean ranges. We selected populations at two extremes of the gradient: 1200 and 2200 masl. We compared seed abundance, seed rain, seed germination and survival; we also estimated plant recruitment and population growth rate using a constrained life cycle including two stages: seeds and adults. Seed rain, survival, germination and seed density were significantly higher at 2200 masl. In contrast, plant recruitment probability and population growth rate were significantly higher at 1200 masl. Thus, seed stages is limited at higher altitude while the transition of seeds to adult plants is constrained at lower altitude. In spite of the population growth rate is lower at higher altitude, it is still higher to 1 which suggest the potential of an active colonization of this exotic plants to higher altitudes. Acknowledgements: ICM-P05-002, PFB -23 and CONICYT. Effects of bamboo flowering and overstorey neighborhood on tree seedling establishment in a mixed Patagonian forest CACCIA F.D.* (1); KITZBERGER T. (2) and CHANETON E.J. (1) (1) Universidad de Buenos Aires, Facultad de Agronomía (2) INIBIOMA, CONICET; U.N. Comahue, Lab. Ecotono *fcaccia@agro.uba.ar We conducted a 2-year field experiment to examine how overstorey neighborhoods identity and episodic bamboo flowering affect seedling recruitment in a mixed temperate forest at Lago Currhué Grande, Lanín National Park (Neuquén, Argentina). Treatments consisted of a factorial combination of overstorey identity (Nothofagus alpina or N. dombeyi), bamboo patch conditon (flowered/dead or non-flowered/alive) and access to rodents (with or without exclosure). We planted 8 pairs of newly emerged N. alpina and N. dombeyi seedlings in each overstorey by bamboo combination (n = 5 stands); half of the seedlings in each stand were protected from rodents with a wire exclosure. Rodent exclosures increased seedling survival of both species irrespective of bamboo condition and overstorey identity. N. alpina seedlings survived nearly twice as much under heteroespecific (N. dombeyi ) as beneath conspecific canopy (40 vs 18%) and within flowered bamboo relative to non-flowered patches (41 vs 16%). These patterns resulted mostly from differences in invertebrate predation. In contrast, overstorey identity and bamboo condition had no net effects on N. dombeyi survival. Bamboo flowering decreased invertebrate predation on N. dombeyi seedlings (30 vs 57%), but this effect was cancelled out by higher mortality through abiotic stress. Invertebrate herbivores and abiotic factors both played an important role shaping spatial patterns of seedling establishment of canopy species in this temperate forest. Forest dynamics dominated by Podocarpus parlatorei, in a post-grazed Subtropical Montane forest cronosequence CARILLA J.* Laboratorio de Ecología Regional, Univ Nac Tucumán *julietacarilla@yahoo.com.ar Long term monitoring of forest dynamic is an effective tool for detecting and forecasting forest changes. This study aimed to analyze successional trajectory in subtropical montane forest of NW Argentina; from secondary forest, dominated by Alnus acuminata, Crinodendron tucumanum (Aa – Ct) and Podocarpus parlatorei (Pp), to old-growth forest dominated by Myrtaceae family species (M o-g). Permanent plots were established at 1800 m, in Sierra San Javier, Tucumán, in 1991 and re-measured in 1996, 2001 and 2007. Compositional, demographic and structural variables were calculated, emphasizing in aboveground biomass (AB) as an approach to quantify forest C stores. Aa – Ct forest accumulated AB quickly, reaching 181 tn/ha in few decades, but not persisted, due to Aa short longevity and recruitment dominated by understory species. Pp forests reached high AB values (393 tn/ha), similar as M o-g (407 tn/ha), but decreased as succession progressed due to large individuals death. Intense intra-specific competition of dominant individuals resulted in low structural changes and growth rates. Despite Pp relatively low growth (0.2 cm yr-1), recruitment and mortality rates, it contributed significantly with forest AB (up to 93% of total AB). M o-g biomass showed different patterns between them. Secondary forest composition tended to converge to more diverse M o-g forest, with slow replacement of pioneers by long-lived species, and potentially high C sequestration and storage capacity. Increasing pollination erosion towards an environmentally-determined distribution boundary in a South-Andean Proteaceae CHALCOFF V.R.*; EZCURRA C. and AIZEN M.A. Laboratorio Ecotono - INIBIOMA (UNCo-CONICET) *vchalcoff@gmail.com Variation in pollinator guild composition over the distribution of the geographic range of a plant species can generate a geographically structured mosaic of evolution, so that the degree of overlap with effective pollinators will generate evolutionary hot-spots or cold-spots. The objective of this study was to asses if the geographical distribution of plants can not only be imposed by environmental-driven limits, but also by the effect of reproductive collapse mediated by the absence of effective pollinators. Embothrium coccineum is a red flowered species from southern South America with a generalist pollination system. Whereas the western limit of its longitudinal distribution is physically determined by the Pacific Ocean, the eastern range appears environmentally limited by the arid Patagonian steppe. We determined its most effective pollinator and we evaluated the effect of environment and pollinator in its reproductive success. Despite being a generalist species, E. coccineum has one hummingbird species (Sephanoides sephaniodes) as its most efficient pollinator, and its reproductive success depends on its visitation frequency and the pollen deposited on stigmas, rather than on precipitation. Contrary to the sites where the most efficient pollinator is present (hot-spots), in populations where the pollinator is rare or absent (cold-spots) we recorded a reproductive collapse. These results strengthen the importance of pollinators as biotic controls of plant distributions. Forest characteristics and home range size of Magellanic woodpecker Campephilus magellanicus in the Northwestern of Patagonia, Argentine CHAZARRETA L.* and OJEDA V. Universidad Nacional del Comahue - INIBIOMA *laurachaza@yahoo.com.ar The study of the use of space by animals and its relationships with characteristics of the habitats allows us to understand the species requirements and its ecology. The Magellanic woodpecker (Campephilus magellanicus, Aves Picidae) is the largest picids of the austral temperate forest and inhabits exclusively in mature, pure or mixed Nothofagus spp. forests in Chile and in Argentina. It is territorial and lives in stable family groups. We studied habitat characteristics and home-range size variation in a population of Magellanic woodpecker from a Northwestern Patagonian forest. We determined the home-range size of 8 woodpeckers’ families in order to relate home range size and habitat characteristics. We used a 95% fixed kernel estimator to measure the home range size. Range size along with characteristics of the used habitat was variable among woodpecker families. Smaller home ranges were characterized by big trees (major DBH and heights). Tree density of each home range was also different among families: areas that were depicted by high tree density also had small trees, or on areas with big trees, home ranges were small. Due to the dependency this woodpecker has on the habitat where it lives, it is important to generate information about the extension and characteristics of the forest used by the species. Given the variation in sizes and characteristics of home ranges, we recommend habitat features be considered when designing conservation strategies. Stoichiometric constraints in plant species invasion in Patagonia temporary wetlands CUASSOLO F.*; BALSEIRO E. and MODENUTTI B. Lab. Limnología, INIBIOMA, CONICET-UNComahue *florcuassolo@crub.uncoma.edu.ar During the dry season, temporary or semi temporary wetlands are often invaded by exotic or native terrestrial plants, and when flooded, plant tissues would contribute differently to the elemental composition of the aquatic environment. Potentilla anserina is an exotic species in Patagonia and frequently invade potentially flooded areas. We aimed to analyze stoichiometric constraints of macrophytes species that colonize wetlands, examining elemental relationship (C:N:P) of vegetal tissue (shoots and roots) of three different plant species. Our results showed that C:N did not varied significantly between shoots and roots of each species. On the contrary, C:P was observed to be lower in the roots indicating a higher P allocation. In particular, P. anserina exhibited the lowest root C:P ratios (half that of the native macrophytes). The elemental composition of the vegetal tissue could depend on the presence of micorrhyzal fungi. While no infection was recorded in Carex aematorrhyncha, infection was dominated by arbuscular micorrhyzal in P. anserina and by dark sepatate endophyte in Eleocharis pachycarpa. The differences in micorrhyzal infection and elemental composition would contribute to the success of P. anserina as invader. Plant growth, phenological and morphological traits of nine native and exotic invasive woody plant species in Patagonia DAMASCOS M.A.* (1); LLANCAQUEO Y. (1); SVRIZ M. (2); BARTHELEMY D. (3) and HENSSEN I. (4) (1) Universidad Nacional del Comahue (2) Universidad Nacional del Comahue. CONICET (3) INRA, Umr AMAP, Montpellier, France (4) Martin-Luther-University, Halle, Germany *damascos@cab.cnea.gov.ar Native (NA) woody species of andean-patagonian forest are mainly evergreen (EV=83%) while invasive (IN) species of the same eco region are deciduous (DE=88%). Plant phenology, shoot growth, shoot and fruit morphology were compared between five IN and four NA species in order to determine if studied traits can be explained the IN success. We studied five plants by species and 3-5 shoots by plant. Studied NA species were Ribes magellanicum, (RM, DE), Aristotelia chilensis (AC, wintergreen), Berberis microphylla (BM, EV), B. darwinii (BD, EV). IN included the DE species Rosa rubiginosa (RR), R. canina (RC), R. multiflora (RM), Crataegus monogyna (CM) and Sorbus aucuparia (SA). Shoot extension period, leaves density and seed production varied among species independently of their origin. Specific leaf area (SLA, cm2/g) of DE species was higher for IN than in NA species. Flowering was axilary (RM), occurred on small unbranched shoots (AC, BM, BD) or at the apex of branching shoots (IN). Flowers emerged before (NA), during (CM, SA) or after (RR, RC, RM) shoot extension. NA mature fruits remained on plants during November-March (mean±ES, 139±9 days) while those of IN from March to November (196±19 days) representing an autumn-winter resource for vertebrates. Comparatively higher seed mass, SLA and leaf turnover and different seed dispersion period of IN (compared to NA) could explain the high invasiveness of IN studied species. Intra-annual bird community dynamics in coastal environments of the Cape Horn Biosphere Reserve, Chile DARDANELLI S.*; PIZARRO J.C.; MOLINA R. and ANDERSON C.B. Programa de Conservación Biocultural Subantártica – Parque Etnobotánico Omora y Universidad de Magallanes – Centro Universitario Puerto Williams, Chile. *sebastian.dardanelli@umag.cl The Cape Horn Biosphere Reserve (CHBR) houses the world’s southernmost forest and a great diversity of marine and coastal environments. In this place, birds constitute the most diverse and conspicuous group. For this reason in the CHBR a terrestrial bird monitoring program has been executed since January 2000. Beginning in February 2009, this program also includes shorebirds, constituting the Omora Bird Observatory. We performed 32 transects (16 in bays and 16 in exposed coasts; 800x200m each) on the north coast of Navarino Island during summer and winter. Total abundance was 985 birds in summer and 617 in winter. Species richness was 35 in summer and 36 in winter. In summer, Chloephaga picta (135 individuals), Calidris bairdii (111) and Lophonetta specularioides (83) were the most abundant species, while in winter Charadrius modestus (84), L. specularioides (74) and Larus dominicanus (57) were the most abundant. The exposed coasts presented higher abundance, richness and diversity, but this pattern was different for some species; for example, L. specularioides was more common in bays in both seasons. C. modestus, classified as a migratory species, was recorded during summer and winter. Finally, some “terrestrial” species such as Xolmis pyrope and Curaeus curaeus were recorded on the coast, but only in winter, indicating a seasonal refuge for some passerines. These preliminary results contribute to the poorly known ecology of the coastal avifauna in austral South America. Improving harvesting techniques to ensure Sphagnum regeneration in Chilean peatlands DIAZ M.F.* (1) and SILVA W. (2) (1) Universidad Andres Bello (2) Pontificia Universidad Catolica de Chile *mdiazi@unab.cl The use of fire to clear forests in the temperate region of southern Chile has significantly reduced forest cover and created new wetland areas, which often become dominated by Sphagnum moss. Sphagnum species, primarily S. magellanicum, are used internationally as substrate for horticulture. Chile exports annually 2,250 tons of Sphagnum. Because of growing market demand, exports have increased four times since 1998. Such demand has promoted indiscriminate exploitation leading to a number of potentially negative ecological and social consequences, including disruption of peatlands, changes in water storage capacity of peatlands affecting water supply to rural communities and reduction of biodiversity. We aimed at improving both harvesting techniques to ensure moss regeneration and the sustainability of moss cover in harvested areas. If moss regeneration capacity depends on depth of extraction, it would be expected that with increasing depth, regeneration capacity would decrease. To determine the maximum harvesting depth for moss regeneration, samples were taken and divided into sections associated with different depths. We recorded and marked the number of new shoots of Sphagnum monthly. We found a negative correlation between regeneration (appearance of new shoots) and depth. Our studies showed that 86% of new shoots appeared within the first 10 cm in depth, suggesting that harvesting not more than 10 cm in depth is recommended to attain the highest rates of regeneration. Hypogeous species of Ascomycota and Basidiomycota from the Nothofagus forests of Chile and Argentina. DOMINGUEZ L.S.* (1); SMITH M. (2); NOUHRA E. (1); PFISTER D. (3) and TRAPPE J. (4) (1) IMBIV, CONICET, CC 495, Córdoba, 5000, Argentina (2) Dep. of Biology, Duke University, Durham, NC 27708 (3) Harvard University, Farlow Herbarium, 22 Divinity (4) Oregon State University, Department of Forest Scie *lausudom@hotmail.com Despite important collections by Thaxter (1906) and Horak (1979), the hypogeous fungi of South American temperate forests remain mostly unexplored. Our objective was to collect and describe new taxa in the Nothofagus-dominated forests of Argentina and Chile. By raking the forest soil along transects located within pure and mixed Nothofagus spp. stands, several interesting truffles and secotioid basidiomycetes were encountered. Among the Ascomycota, only one native truffle, Hydnocystis singeri, has been described from South America. Our survey detected undescribed Pezizales truffles in the genera Genea, Peziza (Galactinia clade) and Ruhlandiella as well as putative species of Amylascus and Gymnohydnotrya. This assemblage is an interesting mix of primarily holoartic genera (Genea, Peziza) and genera previously known only from Australia (Amylascus, Gymnohydnotrya, Ruhlandiella). Morphological analyses as well as DNA sequencing of the ITS and 28s ribosomal DNA indicate that these pezizalean truffles fall within primarily ectomycorrhizal clades. Our survey also revealed a wide diversity of Basidiomycota truffles, such as Hallingia and Hysterangium (Hysterangiales), Gautieria (Gomphales), Gymnopaxillus, Octaviania and Scleroderma (Boletales), Radiigera (Geastrales), Setchelliogaster and many species of Thaxterogaster (Agaricales). At least one species of Scleroderma, Radiigera and Setchelliogaster and few species within Octaviania and Thaxterogaster are likely undescribed taxa. Fire cues on Fabiana imbricata seed germination DUDINSZKY N.* and GHERMANDI L. Laboratorio Ecotono, INIBIOMA, CRUB-UNCo *natyadudinszky@hotmail.com Fire may stimulate Fabiana imbricata encroachment in northwestern patagonian grasslands, because post-fire recruitment seems to be a characteristic of Fabiana imbricata shrub. The effect of fire on Fabiana imbricata seeds germination was surveyed under laboratory conditions evaluating the specific effect of temperature, charcoal, scarification and smoke treatments. We designed a factorial experiment where the factors were: smoke (10 min.), temperature (60ºC - 5´, 60ºC-10 ´, 90ºC-5´, 90ºC-10´), scarification (no scarification-scarification) and irrigation with charcoal solution (10g/L). Ten replicates of 10 seeds each were used per treatment. The seeds were placed in Petri dishes in a germination chamber (daily temperatures of 19º C and of 5ºC by night, 12/12 h photoperiod) during two months. In this experiment the applied temperatures seem to have no effect on Fabiana imbricata germination and the same occured with the charcoal treatment. However scarification and smoke treatments significantly stimulated Fabiana imbricata germination. This indicates that the smoke which occurs during grassland fires may be an important cue in the germination and recruitment of this species. Pattern of reproductive allocation in the invasive plant Escholscholzia californica along altitudinal gradient DURAN P.* and BUSTAMANTE R. Universidad de Chile *paz.duran.moya@gmail.com Knowledge on how invasive plants vary in their phenotypic expression along climate gradient is crucial to understand exotic species capability to respond to climate change. The expansion of the invasive species range, will depend on how well exotic species responds to heterogeneity in climate. Altitudinal gradient are convenient scenarios to investigate such responses as they express abrupt climatic variation in short distance. In this study, we examined the elevational variation of reproductive allocation of Eschscholzia californica, an invasive species with USA origins. We sampled three different populations at 1000, 1500 and 2000 masl, in two altitudinal gradient. Individual reproductive traits (flower size and numbers) and reproductive effort were assessed. Results showed that flower size increases across altitude, but the number of flower per individual decreases. On the other hand, reproductive effort decreased with altitude. Our results indicate that E.californica present a reproductive cost which is expressed in a decrease of reproductive effort. In spite of these individual constraints at higher altitudes, it seems that populations will continue expanding across altitudinal gradient. Aknowledge: ICM-P05-002, PFB -23 and CONICYT. Plant diversity along an urbanization gradient in coastal resorts from Argentina FAGGI A.* (1) and DADON J. (2) (1) MACN_CONICET (2) FADU-UBA *afaggi2003@yahoo.com.ar As new and fast growing cities, the coastal resorts are interesting models to study the vegetation changes promoted by urban processes. In order to analyze these changes, seven coastal resorts were chosen: Villa Gesell, Miramar, Necochea, Monte Hermoso, Las Grutas and Puerto Madryn. Three sectors were defined in each city: downtown area, residential area with continuous urban fabric, and residential area with disperse urbanization. Ten blocks were sampled in each sector, discriminating among different patches: lawns and trees along the streetscapes, gardens, vegetated dunes and brownfields. Total richness, native/exotic index, implanted/spontaneous index and coverage per species were calculated in all cases. Total richness was high, since 387 species were recorded; 62% were exotics; 37% implanted. Twenty two implanted species grew spontaneously, 94 plants were characteristic for the dunes and 116 for pastures. Lawns in the central and residential areas showed the higher plant diversity. Richness increased towards the center in some cases and it decreased towards the periurban areas in other. Since these trends changed among different patches inside the same resort, the factors that controlled changes in richness were not clear. A higher proportion of introduced ornamental exotic species were found in the brownfields, dunes and lawns without maintenance, indicating that unplanned changes contributed to increase the homogenization of the biota inside the cities. Metazoan parasites of Aplochiton zebra (Osmeriformes: Galaxiidae) in the Argentinean Patagonia. FERNáNDEZ M.V.* and VIOZZI G. Laboratorio de Parasitología INIBIOMA-UNCo *fernandezmv@crub.uncoma.edu.ar Eight species of galaxiids are distributed in South America, and only the G. maculatus parasites have been studied exhaustively in Argentina. From the 4 galaxiids species present on the east of the Andes, Aplochiton zebra (peladilla) is distributed discontinuously from the 42°20´ to Tierra del Fuego and the Malvinas Islands. In Argentina 3 species of parasites were registered meanwhile in Chile only 2 species were cited. The aim of this research was to study at regional scale A. zebra´s parasites. Fish were collected with nets in 4 Patagonian lakes (42° 50´S to 52° 20´S), examined for parasites, and data about stages, site of infection, prevalence, and mean intensity were recorded. From the 108 peladillas examined, 13 species of metazoan parasites were found: 4 myxozoans, 3 digeneans, 1 cestode, 1 acanthocephalan, 3 nematodes and 1 bivalve. Unlike G. maculatus, no monogeneans were registered and the majority of the parasites are generalists and also parasitize G. maculatus. This research contributes to the knowledge of the A. zebra parasitofauna. Since this species has a wide distribution range and there is scarce information about its biology, this research is a contribution to a better knowledge of this galaxiid. Performance of the southernmost lizards of the world: Liolaemus sarmientoi and Liolaemus magellanicus FERNáNDEZ J.* and IBARGüENGOYTíA N. Centro Regional Universitario Bariloche *jimefernandez14@gmail.com The performance in lizards generally increases with body temperature (Tb) but may decline beyond an optimal temperature (To). We studied the thermal sensitivity and performance of L. sarmientoi (N=39) and L. magellanicus (N=15) from 51ºS (Santa Cruz, Argentina). Running speeds were recorded by video camera for long runs (LR, 1m) and sprint runs (SR, 0.2m) in nature at three air temperatures (17, 21, and 30ºC). When air temperatures were low, both species were faster in SRs than in LRs, but at high air temperatures L. sarmientoi was faster at LRs than in SRs. L. magellanicus did not show differences between LRs and SRs at high air temperatures. The To for L. sarmientoi was 36ºC (LR) and 27ºC (SR) and the performance breadth (B80) which equals 80% of To , was 25-36ºC for LRs and 27-31ºC for SRs. The To’s for L. magellanicus were 34ºC (LR) and 32ºC (SR), and B80 was 30-34ºC for LRs and 27-32ºC for SRs. L. magellanicus and L. sarmientoi show suboptimal adaptation to the harsh environments in the extreme south of Patagonia, and reach their maximum performance only at temperatures above those that occur in their current thermal environment. L. sarmientoi maintained high performance over a broad range of temperatures during LRs and was able to achieve a B80 at low temperatures. In contrast, L. magellanicus has the challenge to attained high performance only over a narrow range of temperatures (both LRs and SRs), a range unlikely to occur in nature. Germination responses to experimental burns of two dominant perennial grasses in NW Patagonia grasslands (Argentina) FRANZESE J.* and GHERMANDI L. Instituto Nacional de Investigaciones en Biodiversidad y Medioambiente, Universidad Nacional del Comahue, Lab. Ecotono, Quintral 1250 (8400), Bariloche, Argentina *jfranzese@crub.uncoma.edu.ar Semi-arid grasslands of NW Patagonia are subject to frequent fires. They can impact on the regeneration of native plant species in different ways. The aim of this work was to study the effect of fire on seed germination of the dominant perennial tussock grasses: Stipa speciosa and Festuca pallescens. In field we sowed ten 50 cm diameter plots per species with 50 seeds each. In May 2009, we burned half of the plots per species (Burned treatment), whereas we left the remaining plots as controls (Unburned treatment). There was germination in all plots. The experimental burning inhibited Festuca germination (Burned = 26 % vs Unburned = 41 %), whereas it promoted Stipa germination (Burned = 32 % vs Unburned = 16 %). These results support other ones obtained in lab conditions. The structures which wrap the seeds of Festuca seem to be thinner than the ones of Stipa. As a consequence, Festuca seeds could have had a poor protection of heat. The promotion of germination in Stipa could have been due to the presence of smoke during the burnings since this factor improved their germination in lab experiments. Then, fire occurrence seems to favor Stipa regeneration, and it could have important economic implications since it is an unpalable plant. Mechanisms and impacts of tree invasions: Acacia dealbata (mimosaceae) in the native forest of south-central of chile. FUENTES-RAMíREZ A.* (1); PAUCHARD A. (2); CAVIERES L. (3) and MARTICORENA A. (3) (1) Universidad de Concepción, Laboratorio de Invasiones Biológicas (2) Universidad de Concepción, Lab. Inv. Biológicas (3) Universidad de Concepción, Depto. de Botánica *andresfuen@yahoo.es Plants invasions are one of the main drivers in the global change causing the loss of biodiversity. Acacia genus has been reported as invasive in several countries in the world (e.g. South Africa, Portugal). In Chile, Acacia dealbata was introduced from Australia during the 19th century and it has been documented as invasive. To assess the invasiveness of this species and its impacts in native forests of south-central Chile, we used observational and experimental approaches. We conducted a floristic sampling assessing the species richness in three conditions: inside of A. dealbata stands, in the stand edge and within native forest. Experimentally, we assessed the A. dealbata seedlings survival in these three conditions and we compared with two native species (e.g. Cryptocarya alba and Nothofagus obliqua ). For both approaches we selected five study sites close to Concepcion (Región del Bíobío, 37º S). Species richness was significantly lower inside the A.dealbata stands compared with stand edge and native forest. Survival results showed that A. dealbata and C. alba have a high probability to survive within native forest (ca.85%), while in the edge A. dealbata is the only species able to survive. We concluded that A. dealbata invasion has a negative impact on the species richness and that the species has a high ability to establish inside of native forest, decreasing the local diversity and homogenizing the community. Acknowledgments: FONDECYT 1070488, ICM P05-002, PFB-23. Land Use Change: Implications for a community of rodents in the Chilean Patagonia GARCíA K.* (1); ORTIZ J.C. (1); D'ELíA G. (1) and AGUAYO M. (2) (1) Universidad de Concepción (2) Centro EULA. Universidad de Concepción *kgarcia@udec.cl We evaluated how the patterns of land use affect the community of rodents present in Patagonian Andean habitats over the course of a year. The habitats included mature forest, second growth forest, forest plantations and agricultural grassland. We recorded a total of 341 individuals belonging to eight species of cricetid rodents (Abrothrix longilipilis, A. olivaceus, Oligoryzomys longicaudatus, Irenomys tarsalis, Geoxus valdivianus, Chelemys macronyx, Loxodontomys micropus and Reithrodon auritus). We recorded Irenomys tarsalis and Geoxus valdivianus in the Pinus contorta plantation, which is the first record of these species in this habitat. We found a negative gradient of diversity from the second growth forest to the grassland. However, we did not find significant differences in diversity, evenness or species richness among the four habitat types. We only found significant differences in total population abundance and habitat; we found a gradual decrease in total abundance from the mature forest to the grassland. The general tendency was for an increment in abundance from summer to autumn, with a decrease in winter and spring. Finally, the results indicate that some species are more tolerant to perturbed habitats than previously thought, and that rodents mainly distinguish between tree cover and herb cover more than the species plant composition of an area. Geographical patterns in folivory across insect guilds in Nothofagus pumilio correlates with temperature and leaf traits GARIBALDI L.A.* (1); KITZBERGER T. (1); CHANETON E.J. (2); MAZíA C.N. (3) and RUGGIERO A. (1) (1) Laboratorio de Ecotono, INIBIOMA-CRUB, Bariloche (2) IFEVA, CONICET-Facultad de Agronomía, UBA (3) Cátedra de Dasonomía, Facultad de Agronomía, UBA *garibald@agro.uba.ar Abiotic conditions and leaf traits may regulate folivory patterns across scales. However, guild-specific responses to these controls along major environmental gradients are not clear. We studied spatial variation in folivory by different insect guilds in Nothofagus pumilio forests along its entire geographic range in Argentina (38-55º S, 66-73º W, 0-1700 m a.s.l.). In these forests, temperature may be suboptimal for insects and thus spatial changes in temperature may affect insect survival and folivory rates. We expected that better climatic insulation in concealed feeding guilds (gallers, miners, leaf tiers) may promote a weaker response to temperature changes than in external feeding guilds (pit feeders, skeletonizers, chewers, suckers, bud feeders). We found that leaf damage frequency decreased with forest elevation and latitude for all insect guilds. Overall, leaf damage was positively related with mean annual temperature. Although the strength of this association varied across insect guilds (and thus guild composition across sites), there was no consistent differential response between internal and external feeding strategies. Similarly, leaf size was positively correlated with leaf damage by all insect guilds. We suggest that geographical variation in folivory rates may be controlled by abiotic and biotic factors that consistently impact on different insect guilds. Ours results have implications to understand the effects of climate change on insect herbivory. Growth rates of Chilean rainforest tree species are paradoxically decreased by addition of nitrogen via increases in soi GAXIOLA A. (1) and ARMESTO J.J.* (2) (1) Instituto de Ecología y Biodiversidad-U. Católica de Chile (2) CASEB, IEB *aurora.gaxiola@cantab.net The effects of changes in soil nitrogen (N), and in some cases phosphorus (P) concentrations, have been reported for forests in the northern hemisphere, and recent attention has also been paid to some ecosystems in the southern hemisphere. Additionally, recent studies have established that ecosystem responses to nutrient addition are predominantly determined by soil stoichiometry (i.e C-to-N-to-P ratio) rather than the absolute amount of any particular nutrient. Chilean temperate ecosystems have not historically been exposed to high inputs of atmospheric N and therefore could be susceptible to anthropogenic increases in atmospheric N. Furthermore, the high rainfall regimes in southern Chile could led to rapid P depletion. Hence, the combined effects of increasing soil N and the reduction in P is likely to lead to rapid changes in N:P ratios that could induce long-term ecosystem changes. We experimentally tested if higher soil N-availability increased N:P, and differentially decreased growth of pioneer versus late successional species. We found that growth rates of Chilean rainforest tree species are paradoxically decreased by addition of nitrogen via increases in soil N-to-P ratios. Experimental analysis of the effects of climatic variables on microbial communities of a temporary pond (Patagonia, Arg) GEREA M.* (1); SOTO CáRDENAS C. (2); REISSIG M. (1); UNREIN F. (3) and QUEIMALIñOS C. (1) (1) Universidad Nacional del Comahue - CONICET (2) Universidad Nacional del Comahue (3) IIB-INTECH CONICET *marinagerea@gmail.com Temporary ponds are especially sensitive to climatic changes. The gradual increase in mean annual temperature and the variations in rainfall affect water levels and, in consequence, influence on the natural eutrophication processes. In order to analyze the synergic effect of these variables on microbial community dynamics, we simulated two possible climatic scenarios with variations in water levels and nutrient concentrations through the addition of aquatic avian feces. We performed experiments in mesocosms with a 2 x 2 factorial design, where water level (Deep and Shallow) and feces addition (With and Without Feces) represented the principal factors. An equal mass of sediments were added to all mesocosms to allow the colonization of resistance forms. We analyzed nutrient and microbial community dynamics during 10 weeks. A noticeable gradient in nutrient concentration was observed between the four treatments. The development of bacterial community showed a correspondence with phosphorus variations. Bacterivorous nanoflagellates and ciliates presented differential dynamics in the four treatments, with an important prevalence of mixotrophic algae in the Deep one. Meanwhile, heterotrophic nanoflagellates better developed in the treatments With Feces. These results indicate a synergic effect of the forcing variables, with more complex links between competition and predation processes in the enriched treatments. Ecophysiological traits may explain the dominance of climbing plant species in a southern temperate rainforest GIANOLI E.* (1); SALDAñA A. (2) and JIMéNEZ-CASTILLO M. (3) (1) Universidad de La Serena; CASEB (2) Universidad de Concepción (3) Universidad Austral de Chile *egianoli@userena.cl Climbing plants are a key component of tropical rainforests. Little research on the ecology of climbing plants has been conducted in temperate forests. In a southern temperate rainforest, we addressed whether the importance value (average of relative abundance and frequency) of climbing plants in two distinct light environments, treefall canopy gaps and mature forest understory, was associated with ecophysiological traits related to light exploitation. In canopy gaps the importance value of climbing plant species was inversely associated with leaf area, with the exception of Hydrangea serratifolia, a massive liana that dominates the surrounding understory. Small leaves may help to minimize transpiration water loss in gaps during the growth season, which coincides with decreased rainfall. Species with lower photosynthetic rate, dark respiration, and specific leaf area were dominant in the shaded forest understory. The patterns in gas exchange rates are consistent with a strategy of lowering metabolic costs in a limited resource environment. Thicker leaves are associated with leaf longevity in the shade, where tissue replacement is very expensive. Patterns of ecophysiological traits along the light gradient found for climbing plant species are consistent with those reported for tree species. Variation in achene traits of the native Helenium aromaticum is associated with fire frequency in the Chilean matorral GóMEZ-GONZáLEZ S.* (1); GIANOLI E. (2); BUSTOS C. (3) and TORRES P. (4) (1) Universidad de Concepción; IEB (2) U. Concepción; U. La Serena; CASEB (3) Universidad Austral de Chile (4) Universidad de Concepción *sgomez@udec.cl Because fire is not a natural disturbance in the Chilean matorral, it is thought that native plant species have not evolved under this pressure. However, anthropogenic fires have occurred in the matorral since prehispanic times and therefore could have selected for adaptive traits in the native flora. Our aim was to determine whether the interpopulation variation in achene traits of the native annual Helenium aromaticum is associated with fire frequency, thus suggesting selective processes driven by fire. We collected mature achenes of 25 H. aromaticum plants in 10 populations across central Chile. Fire frequency at each site was estimated by constructing a fire-scar chronology from boles of Acacia caven trees. We performed correlation analyses to test the association between fire frequency and achene traits of H. aromaticum. Fire frequency was positively correlated to angle, shape factor (circularity), width/length ratio and pubescence of the achenes. In contrast, there were no significant correlations with achene size traits. Regardless of achene size, more pubescent and rounded achenes could better protect the embryo from the high temperatures reached during a fire. We hypothesize that anthropogenic fires are exerting a selective pressure on seed traits of native matorral species, driving evolutionary change. Updated list of Eriococcidae (Hemiptera: Coccoidea) in Patagonia, Argentina GONZáLEZ M.P.* Facultad de Ciencias Naturales e IML. INSUE. Tuc *mopagon2004@yahoo.com.ar Argentina Patagonia is a vast region represented for two eco-regions, forests and Patagonian steppe. In the first were cited four genera and nine species of Eriococcidae mainly on Nothofagus (Fagaceae), all very similar to eriocccidae of New Zealand. The aim of this work is to update the list of Eriococcidae species in Patagonia, Argentina. The studied material comes from samples collected in this region in the period 1996 - 2004 and it is deposited in the Collection of Instituto-Fundación Miguel Lillo (IMLA), Tucumán, Argentina. We recorded seven genera and 18 eriococcidae species in Patagonia, 14 of them on Nothofagus (including two new species not published) and one species on Myrceugenia (Myrtaceae), present in the Patagonian forests. Three species, two on Larrea (Zygophyllaceae) and one on Stipa (Poaceae) are cited in the steppe. Hosts data are provided. Postfire growth of two dominant tussock grasses in northwestern Patagonia grasslands GONZALEZ S.* (1); GHERMANDI L. (2) and PELáEZ D. (3) (1) Universidad Nacional del Comahue-INIBIOMA (2) Universidad Nacional del Comahu-INIBIOMA (3) CERZOS *sgonzalez@crub.uncoma.edu.ar Fire affects plant survival and growth. Our aim was to evaluate the fire effect on growth of two native tussock grasses, Festuca pallescens (very palatable) and Stipa speciosa (unpalatable). In May 2008, plants of each species were exposed to low temperature (200-400ºC), high temperature (500-700ºC) and no fire (control) (n=9 per treatment and per species: 54 plants in total). We removed the biomass before all the treatments (included control), and we burned plants with a portable burner device. From September 2008 to March2009, we monitored the length of six tillers per plant of each treatment. We registered low mortality after fire, 2% in F. pallescens, and 0% in S. speciosa in both temperature treatments. F. pallescens resprout length was higher in control treatment than in temperature treatments while S. speciosa tiller growth was similar between fire and control treatments in October and November monitoring dates. Comparing between species, the S. speciosa tiller growth was higher than in F. pallescens (only in low temperature treatment). We concluded that fire is relevant in determining the resprout growth of both species during the first postfire growth season. A low intensity fire would benefit the S. speciosa growth compared to F. pallescens, affecting their population dynamics. Moreover, being S. speciosa unpalatable species rarely consumed by livestock, also the productivity of grasslands would be affected. Successional pathways and carbon balance of old primary evergreen forests of Chiloé Island, Chile GUTIERREZ A.G.* and HUTH A. Helmholtz Centre for Environmental Research - UFZ *alvaro.gutierrez@ufz.de Old-growth forests are commonly assumed in steady-state, representing a final successional stage when forests have stable structure and neutral carbon balance over long periods in the absence of major disturbances. In forests containing long-lived tree species (>600 years old), the time needed to enter this stage might be long hampering the recognition of old-growth stands. Here, we propose a method to recognize the old-growth stage using an individual oriented process-based forest model. We analyzed primary old forests located in northern Chiloé Island, Chile (N=13, >170 years), parameterized the model using field data and literature sources, and evaluated the model performance to simulate forest dynamics. The model reproduced the structural and compositional variability of the studied forests, when variable successional pathways were considered. The dominance of pioneers emerged during the first 500 years of succession due to their long life-spans and canopy openings produced by windstorms. Around half of the studied forests have not reached steady-state. Forests will decrease in biomass due to the death of big pioneer trees (eg. Eucryphia) potentially producing carbon losses (ca. 1.7 tonnes of carbon ha/year). Old-growth forests in this region contain large quantities of carbon, are variable in their carbon flow and can take up to 850 years of succession to reach this stage. These characteristics should be considered in management, conservation and restoration strategies. Thermo-physiological and growth responses of Liolaemus pictus argentinus to altitudinal environmental constraints GUTIéRREZ J.A.* and IBARGüENGOYTíA N. CRUB *jag2980@yahoo.com.ar Many reptiles that live in cold environments limit their activity due to their long periods of hibernation which increases along with latitude and altitude, affecting daily and seasonal activity periods, body temperatures and growth. In this study, the thermo-physiological responses, growth, age, longevity, and fecundity of two populations of Liolaemus pictus argentinus, from the same latitude in Bariloche, but different altitudes: Challhuaco Mountain (1615-1769 m asl) and Melipal beach (771 m asl) were compared. The Challhuaco population had lower body temperatures (Tb = 29ºC) than the Melipal population (33ºC), while preferred temperatures (TP) were similar (TP, Challhuaco=36.7; TP, Melipal=36.6). The index of effectiveness of the thermoregulation (E) showed that L. p. argentinus in the Challhuaco behaved as a moderate thermoregulator (E = 0.4), while in the Melipal population behaved as a moderate thermoconformer (E = -0.24) .Both populations were able to maintain similar growth rates and longevity by means of thermoregulation, showing the plasticity of this species to adapt to different environments. The only differences found corresponded to a broader age range at sexual maturity in Challhuaco (3 – 6 years) and lower longevity (8 years). In Melipal, instead sexual maturity was achieved at 4 years, with a lifespan of 9 years resulting in higher fecundity (11.25). Irrespective of age, the minimum body size shows to be the main factor in the acquisition of sexual maturity. Climate effects on establishment responses of Nothofagus pumilio and N. dombeyi in northwestern Patagonia HEINEMANN K.* (1) and TERCERO BUCARDO N. (2) (1) Universidad Nacional del Comahue (2) Laboratorio Ecotono-INIBIOMA-UNC *karinheinemann@gmail.com Climatic variability is one of the most important factors for tree population dynamics. It may have direct effects on establishment and mortality, but also indirect effects, mediated by disturbances related to climate. In northwestern Patagonia (NWP), in a time scale of decades and centuries, the major vegetation changes both at a local and al a landscape level have been attributed, among other factors, to changes in precipitation regimes. The objective of this study was to asses the influence of precipitation variability on post-disturbance establishment patterns of Nothofagus pumilio (lenga) and N. dombeyi (coihue) in NWP. In different post-fire sites and in tree-fall gaps, in xeric as well as in moist forests, core samples were taken and seedlings of the post-disturbance regeneration cohort were harvested. Establishment dates were determined by dendrochronological techniques, and these were correlated to precipitation chronologies, employing a Superposed Epoch Analysis (SEA). Recruitment in xeric lenga forests was significantly related to periods of higher rainfall. Conversely, in moist lenga forests as well as in coihue forests, establishment was not found to be related to variations in rainfall. In this region, variability in precipitation amount has a greater impact on regeneration in xeric forests than in moist forests. Thus, xeric forests will be more affected in case of a change in precipitation regimes, if the tendency goes towards a lower variability. Effects of land use conversión over nutrients exportation on catchments from the Cordillera de la Costa, South of Chile. HERVE FERNANDEZ P.*; OYARZúN C. and MULSOW S. Instituto de Geociencias, UACh. *pedroherve@hotmail.com We analized runoff and throughfall precipitation per storm event in two small watersheds with different land use (native and exotic) as well as on a closeby grassland (no trees). In both catchemnts and in the nearby grassland, located on the coastal zone of Southern Chile, we measured nutrients (DIN species, DON, TN, TP and PO4-3), as well as the major cations constituents of the water collected (Ca+2, Mg+2, Na+ and K+). Our results show that NO3-2-N concentration was different (p < 0,01) on the runoff water samples. It was higher in the cathcment with the lowest native land cover (Exotic) 78.6 ± 18.6 µg•L-1 in contrast to the native land cover (levels near to detection limits). Mg+2 and Na+ concentrations behave differently in the runoff water fraction, than that of Ca+2 and K+, in the studied areas. Nutrients showed no differences on throughfall precipitation water samples. However, K+ concentration did show significant differentces between the watersheds and grassland. We presented here preliminary data and we discuss them in function of the geographical and landuse coverage of both sites. Stand growth model for Nothofagus antarctica primary forests IVANCICH H.* (1); MARTíNEZ PASTUR G. (1); CELLINI J.M. (2); LENCINAS V. (1) and PERI P. (3) (1) CADIC-CONICET (2) UNLP (3) UNPA-INTA-CONICET *horacioivancich@yahoo.com.ar The estimation of growth is crucial in the forest planning, for this reason the objective was develop a stand model in pure forests of Nothofagus antarctica of complete density in a site quality and ages gradients. The sample was obtained in an age gradient (20 to 220 years) and site quality (IS50= 2.5 to 10.8 m). In each plot, data of forest structure and samples for tree-ring measurement were taken in all trees (n= 1480), in order to estimate growths using biometric models previously developed. To fit the model the growth values of each plot during the last twenty years were calculated, using the ratio of total volume increment/basal area as variable to be estimated. The developed model brings this relationship in function to the site quality and stand age. The statistics (r²= 0.804, mean error= 0.0002, absolute mean error = 0.028), residual analysis and biological behavior were satisfactory. Values obtained through this model multiplied with the stand basal area offers the volumetric growth per hectare per year. The obtained values varied between: 15-40 years between 0.31-0.16 m³.m-².ha-1.year (site I) and 0.08-0.05 m³.m-².ha-1.year (site V); and 160-200 years between 0.07-0.06 m³.m-².ha-1.year (site I) and 0.025-0.022 m³.m-².ha-1.year (site V). The obtained stand growths varied between 1.3-8.3 m³.ha-1.year. This simple model allowed obtaining precise growth values at stand level from of easy mensuration and estimation variables. Extreme climatic events and changes in the assemblage dynamicsof annual herbs in semiarid zones JIMéNEZ M.* (1); GAXIOLA A. (2); ARMESTO J. (2); JAKSIC F. (3) and GUTIéRREZ J. (4) (1) CASEB, IEB, IRECA-UNSA (2) CASEB, IEB (3) CASEB (4) IEB, Universidad de la Serena *mjimenez@bio.puc.cl Extreme climatic events such as floods and droughts are considered stochastic perturbations that modify the community processes. Ecosystems with fluctuating resources are considered to be susceptible to the introduction of exotic species. Arid and semiarid shrublands are characterized by spatial and temporal heterogeneity, so they seem to be a good model for studying this kind of processes. In the semiarid Central zone of Chile, there is a long-term experimental site, Parque Nacional Bosque Fray Jorge (PNBFJ). This zone is particularly affected by ENSO events. We have a 18-year data base, which lets us to make inferences about the influence of extreme climatic events in this ecosystem. The objective of our study is to determine the effect of extreme climatic events on the structure of native and exotic annual plants of the semiarid zone of Chile. We considered year 1998 as an extreme climatic event (drought). We will work with the of plant cover of 21 native species and 8 exotic species. We have used Multivariate techniques to analyze these data. Our results show that the annual assemblage structure before drought (1998) is significantly different from that after 1998. The variance of years before 1998 is explained by native species while the variance after 1998 is explained by exotic species and one native species. We conclude that extreme climatic events, such as droughts, change the dynamics, structure and invasibility of annual assemblages in semiarid ecosystems. Niche model and genetics show opposite responses to glaciations in Patagonian trees with contrasting cold tolerances KITZBERGER T.*; SOUTO C.; ARBETMAN M.; MATHIASEN P. and PREMOLI A. Universidad Nacional del Comahue-INIBIOMA CONICET *kitzberger@gmail.com Environmental change produces multiple effects on species generating complex reshuffling of novel combinations. Projection of modern-trained ecological niche models (ENMs) onto past environmental conditions allows retrodicting distribution of species and pinpoint possible refugia. In addition, spatial patterns of genetic variation allow reconstructing persistence/migration based on the imprints left by past genetic bottlenecks occurred during range shifts. We present ENM-genetic studies of Nothofagus pumilio and Austrocedrus chilensis, two species with contrasting cold tolerances. ENM models show that LGM suitability of A. chilensis was high in a northerly area in Chile (c. 36°-38°S) while areas with current presence were largely unsuitable. Unique alleles and allelic diversity are highest in Chilean populations, decreasing sharply across the Andes and steadily southwards. In contrast, N. pumilio shows multiple areas that remained suitable during LGM throughout its current distribution (35-55°S). No large-scale trends in spatial genetic variation are evident but instead it is related to local movements of ice sheets. All this suggests highly different patterns of persistence/migration in these two species: A. chilensis having suffered isolation in a northerly refugium followed by long-distance eastward (transandean) and southward migration; N. pumilio having persisted locally in ice-free margins followed by short-distance recolonization onto deglaciated areas. Rainforest community assembly: functional and phylogenetic components to interpret current and historic distributions KOOYMAN R. (1); CORNWELL W. (2); ROSSETTO M. (3) and WESTOBY M.* (1) (1) Macquarie University, Sydney, Australia (2) University of British Columbia, Vancouver, Canada (3) Nat. Herbarium of NSW, Sydney, Australia *robert@ecodingo.com.au;rkooyman@bio.mq.edu.au Objectives: Measure and partition the influence of phylogenetic diversity, functional trait values, and environmental gradients on community assembly in Australian rainforest that is naturally patchy in distribution across a large geographic area with high habitat heterogeneity. Methods: Trait-gradient analysis partitioned woody species trait values between alpha and beta components for 596 samples and 1136 taxa. Community phylogenetic structure was measured using a range of metrics, species pools, and null models. Environmental variables, trait values and phylogenetic structure across scales were modelled, and measured using K statistics. Phylogenetic structure metrics were used to look for regional to local patterns of influence of bio-geographic and evolutionary history on community assembly processes. Results: Different correlation structures for alpha and beta components of traits reflect differences in assembly processes across scales. Species turnover (spatial and temporal) in relation to environmental gradients differed within and across regions. The variance partitioned in the patterns of phylogenetic structure reflected spatial and historic (biogeographic and evolutionary) components of community assembly. Conclusions: Understanding functional trait relationships and how they interact at different spatial and temporal scales with phylogenetic diversity and environmental gradients is crucial for understanding potential plant responses to changing conditions. Vegetation recovery with organic matter additions in semiarid Patagonia: Is it a matter of water or nutrients? KOWALJOW E.* and MAZZARINO M.J. CRUB - INIBIOMA *ekowaljow@crub.uncoma.edu.ar Wildfires in semiarid lands can modify soil nutrient cycling affecting vegetation reestablishment. Organic matter additions to burned soils are associated with an increase of water storage capacity and nutrient release. This work involved a three-year study of the impact of a single application of two amendments with high organic matter contents on a burned ecosystem (shrub-steppe) in semiarid Patagonia. Four treatments were evaluated: biosolids compost and municipal solid waste compost (at 40 Mg ha-1), inorganic fertilizer (100 kg N and 35 kg P ha-1), and no application. Soil moisture was monthly measured and contents of soil organic carbon, inorganic N and available P were determined after one and two years after application. Aboveground phytomass of the dominant species was evaluated after two and three years after application. Composts increased soil organic matter but, contrary to expectations, did not increase soil moisture. Both composts increased soluble N but to values much lower than the inorganic fertilizer; however, biosolids composts increased extractable P to even higher values than the inorganic fertilizer. Compared with the control, phytomass values, especially those of perennial grasses, were higher with the inorganic fertilizer and intermediate with both composts. These results imply that, at the same soil moisture, plant growth in this disturbed ecosystem was limited by N availability. Growth and age of two populations of Homonota darwini (Gekkota: Phyllodactylidae) from Rio Negro and Chubut, Argentina KUBISCH E.* (1); PIANTONI C. (2) and IBARGüENGOYTíA N. (1) (1) Centro Regional Universitario Bariloche (CRUB) (2) Dto de Fisiologia, Instituto de Biociências,Brasil *ekubisch@hotmail.com In this study, we describe the growth dynamics of two populations of Homonta darwini: from Chubut (CH) and Rio Negro (RN), Argentina. We address two questions: (1) Do populations exhibit different bone growth patterns? (2) Do they vary in body size, age, and growth according to a latitudinal gradient? Skeletochronology was used to obtain estimates of individual age. Both populations present similar bone growth patterns and partial endosteal resorption of the embryonic and first growth-ring. Nevertheless, remodeling did not hinder accurate age determination. In both, growth fits a sigmoidal curve represented by a linear growth in juveniles and asymptotic in adults. Age of juveniles ranges from 1 to 3 years old in CH and from 1 to 4 in RN, and of adults, from 3 to 9 in CH and from 3 to 7 in RN. In sum, RN’s juveniles show lower specific growth rates than CH’s, while RN’s adults present higher growth rates than CH’s (CH: 0.458-0.008 mm/(year*mm) for 20.74 and 48.52 mm SVL geckos, RN: 0.297-0.036 mm/(year*mm) for specimens of 22.80 and 47.00 mm SVL). However, both populations achieve sexual maturity at the same age. A shorter longevity in RN results in a lower maximum fecundity of 5 hatchlings, while in Chubut results in 7. This plasticity agrees with the high versatility of this species to colonize a broad latitudinal range. We stress the need for further investigations, in order to provide further explanation about the main source of variation between these two populations. Environmental factors associated to group formation in a communal roosting bird, the Andean condor LAMBERTUCCI S.* and RUGGIERO A. Laboratorio Ecotono - INIBIOMA-CONICET *slambertucci@yahoo.com Group size in animals is a dynamic variable that may respond to environmental factors and internal group forces. We used a communal roosting bird, the Andean condor (Vultur gryphus), as model species to test how group size in communal roosts may respond to environmental factors representative of four hypotheses: room availability, climatic refuge, insolation and size of food eaten. We estimated the number of condors that roost daily (=group size) at each of seven communal roosting places in north-western Patagonia, Argentina. A total of 2082 groups were observed over 1042 days of survey. Partial regression analysis was used to partial out different components of group size variation. Critical, mean and median group size varied from 7-28, 4-28, 2-24 individuals respectively, and increased in larger roosts with rainy and colder climatic conditions, low seasonality in precipitation and temperature and moderate levels of insolation. The shared effects of room availability and climate explained a greater proportion of group size variation that either of them considered separately. The size of food items locally consumed had little influence on group size variation. Temperature was the main factor affecting group size along the year. In general, group size increased with unfavourable conditions, but some seasonal variations exist. The Andean condor supported the climatic refuge hypothesis as suitable explanation to account for aggregation patterns in communal roosting birds in temperate regions. Our analysis emphasizes the importance of exogenous climatic factors to account for group formation in social birds. Elemental stoichiometry in calanoid copepods of lakes and ponds from Patagonia LASPOUMADERES C.*; MODENUTTI B.; SOUZA M.S. and BALSEIRO E. INIBIOMA *claspoumaderes@crub.uncoma.edu.ar Energy and nutrient transfer may be limited by the specific needs of each organism, affecting the element availability for higher trophic levels. Consumers are frequently affected by the elemental availability on their food. Thus, omnivorous feeding provides alternative pathways for obtaining a nutritionally balanced ration, hence increasing the acquisition of the limiting nutrient through a diverse resource. Parabroteas and Boeckella are gondwanic calanoid copepods inhabitants of lakes and ponds in Patagonia. These copepods have diverse trophic strategies including omnivory, herbivory and predation. Our main goal was to study if these copepods present a differential homeostatic regulation according to their trophic strategy. We carried out a field survey in different lakes and ponds and a field experiment in order to test interactive effects of light and nutrients on copepod stoichiometry. Results showed that the elemental C:N ratio did not vary significantly between species, whereas C:P ratio did. Herbivorous copepods were strictly homeostatic along the life cycle, while predators were observed to be non strictly homeostatic both in N and P. Our experimental data showed that light and nutrient interact in the final result of copepod body elemental composition, affecting copepod response to environmental stress. Trophic cascade effect: leaf-cutting ant nests, plants, aphids and tending ants LESCANO M.N.* (1) and FARJI-BRENER A.G. (2) (1) Laboratorio Ecotono-CRUB-UNCOMA (2) Laboratorio Ecotono-CRUB-UNCOMA, INIBIOMA- CONICET *natilescano@crub.uncoma.edu.ar In a trophic chain, bottom-up effects can be affected by the presence of small-scale soil disturbances enhancing resource availability. An increase in the quantity or quality of resources at basal levels would allow more energy flow through the trophic chain. If the individuals in the upper levels are efficient in resource exploitation, their population size and species richness may increase. In Patagonian desert steppe, we evaluated how the high nutrient availability generated by the leaf-cutting ant Acromyrmex lobicornis refuse dumps (RD) affects ants-aphids-thistle interactions. We selected plants of Onopordon acanthium growing in RD and non-nest soils (NNS). In each plant we measured nitrogen content (N), height, number of leaves and inflorescences, aphid density, and abundance and number of attending ant species. Plants in RD had higher foliar N and were larger than those in NNS. Aphid density and ant abundance attending them were higher in plants growing in RD. This suggests that the increase in the quality of O. acanthium as a result of growing in RD improves aphid abundance, and larger aphid populations may sustain more ant individuals. Our results suggest that the higher soil fertility generated by leaf-cutting ant nests can affect plant size and quality, and in turn, aphid abundance and their tending ant assemblage. Thus, the small-scale soil disturbances can spread through the trophic chain. Project sponsored by FONCyT, PICT # 25314. Sapling growth in canopy gaps of Nothofagus pumilio forests in Chubut, Argentina LóPEZ BERNAL P.M.* (1); BAVA J.O. (2); SCHLICHTER T.M. (3) and CHRISTIANSE A. (4) (1) CONICET-CIEFAP-UNPSJB (2) CIEFAP-UNPSJB (3) INTA (4) UNPSJB *plopezbernal@ciefap.org.ar In lenga forests with summer water deficit, such as those on the east of their distribution in the Chubut province, seedlings establishment is determined by the canopy openness level. For this reason it is recommended to manage these forests through the Group Selection System, which involves the creation of canopy gaps. However, the saplings requirements could vary during its development, so it is necessary to know how gap size affects saplings growth, once the establishment instance was passed. We analyzed 45 gaps with advanced regeneration in 6 sites with different precipitation levels (750 to 1300 mm/year) and of different sizes (0.8 to 2 times the average canopy height). In each gap we installed 5 subsamples representative of its center. Saplings density, diameter and height growth, and stem shape of the dominant saplings were measured. Additionally, a stem analysis was performed in the highest sapling of each gap. On the whole analyzed rainfall range, sapling growth is positively correlated with gap size, whereas the growth was slightly lower in the wettest sites, probably because these sites have less permeable canopies. To maximize growth and improve saplings shape, we recommend cuts tending to create gaps of sizes between 1.5 to 2 times the average canopy height. At sites with water deficit during the summer, this should be achieved through two cuts (opening and expansion), while in sites without water deficit, this could be done through a single operation. Limitations to the regeneration of tree native species in Pinus radiata plantations LóPEZ-VARGAS G.T.*; BUSTAMANTE ARAYA R.O. and RIVERA-HUTINEL A.A. Dpto. Cs. Ecológicas, Fac. Ciencias, U. de Chile *gioconda.lopez@gmail.com Pine plantations are becoming important component of landscapes in the southern hemisphere. In Chile, Pinus radiata plantations are mainly concentrated in the Central area, thus replacing and fragmenting the native forests. Plantations have been traditionally considered "biological deserts" with conditions and resources that would prevent the sustaining of native biodiversity. In this study, we examined whether in pine plantations there exist limitations to the regeneration of Chilean native trees such as Aextoxicon punctatum, Persea lingue and Drimys winteri. To do this, we compared seedling abundance, seed dispersal, survival and germination and seedling growth between pine plantations and native forest. For the three species the seedlings abundance was significantly higher in native forest that in pine plantation. Seed dispersal was significantly lower in pine plantation compared with native forest, while seed predation was significantly higher. Seed germination and seedling growth did not differ between habitats. Both habitats resulted different in canopy cover and litter composition but similar in soil moisture, suggesting that similarity in germination could be related to similarity of soil moisture between environments. Thus, the difference in seedling abundance between plantations and native forest may be explained by dispersal/seed survival limitations but not to by germination limitations between environments. Project Conicyt-PBCT ACT34/2006. Patch features rather than size determine the impact of fragmentation on forest bird densities MAGRACH A.*; LARRINAGA A.R. and SANTAMARIA L. IMEDEA (CSIC-UIB) *ainhoamagrach@hotmail.com Only 175 years after Darwin visited the island of Chiloe, what he described as "an island covered by one great forest" presents only 38% of forested areas. At this global biodiversity hotspot, forest surface is becoming increasingly fragmented due to unregulated logging, clearing for pastures and replacement by exotic tree plantations. Decrease in patch size, increased isolation and derived "edge effects" can influence species persistence in remnant fragments. We assessed how these variables affect the persistence of a set of birds of key importance for the maintenance of ecological functions in these forests: the frugivorous-bird guild and the most important pollinator in the area (Sephanoides sephaniodes). We also included, as a reference for comparison, the most common insectivorous species (Aphrastura spinicauda). Based on cue-count point surveys (8 points per fragment), we estimated bird density for each of these species in 22 forest fragments of varying size (area), shape and isolation. These patch characteristics, together with habitat variables measured in situ, were used to assess the relationship between forest bird abundance, fragmentation and habitat structure both at the patch and at the point level. Results show bird density varied with connectivity, perimeter and shape, but the hummingbird was the only species significantly affected by patch size. Other features rather than patch size seem to be more important in determining bird abundance in these forests. The effects of forest harvesting in the first stages of lenga leaf litter decomposition in Tierra del Fuego, Argentina MANSILLA P.R.* (1); PANCOTTO V. (1); MORETTO A. (1); VRSALOVIC J. (1) and LENCINAS M.V. (2) (1) CADIC-CONICET (2) CADIC- CONICET *romula81@yahoo.com.ar Nothofagus pumilio (lenga) forests of Tierra del Fuego are mainly managed by shelter-wood cut, but changes of its impacts on decomposition process remain unknown. Our objective is to evaluate lenga litter decomposition in forests of Tierra del Fuego, managed by shelter-wood cut, considering the main associated situations and recovery with time. We focus on three situations: 1) shelter-wood cut area, 2) stockpiled area, and 3) undisturbed forest (control); through the whole cycle management: at 1, 5-10, and 50 years after harvesting (YAH). We evaluated decomposition of organic matter using litter bag method. At three month of decomposition, mass loss was higher (F=11.2, P<0.05) in impacted sites (shelter-wood cut and stockpiled areas) (17%) comparing with control (14.5%). The time since harvesting did not show differences in mass loss (F=1.23, P<0.29), however phosphorous and potassium release were higher (F=8.5 and F=10.4 respectively, P<0.01) for recently harvested forests (1 and 5-10 YAH) than for the older sites (50 YAH). These preliminary results suggest that decomposition process in Tierra del Fuego lenga forests is affected by harvesting, and the recovery to preliminary conditions take more than 50 years. Photo-inhibition in germinative responses of the exotic plant Eschscholzia californica, central Chile: a lab experiment MAREY M.* (1); PEñA-GóMEZ F. (2) and BUSTAMANTE R. (2) (1) Universidad de Chile, Facultad de Ciencias, Instituto de Ecología y Biodiversidad (2) Universidad de Chile,Fac.Cs,Inst. Ecología y Biod. *lyn016@hotmail.com It has been documented that Eschscholzia californica, an herbaceous invasive species of Chile, original from California inhibits seed germination faced to direct light (photo-inhibition). In spite of these eco-physiological responses, this species has been able to colonize high altitudes in Andean mountains where light and radiation are intense. In this study, we assessed the germinative responses of this exotic species disposing seed to different light treatments: 24 hours dark, 24 hours light and 12 hrs light/12 hrs dark. We submitted these treatments to seeds collected from populations of two locations and at two altitudes: 1200 and 2200 masl. Germination rate was higher in darkness regardless location and altitude. In contrast, germination in treatments light and light / dark, was significantly higher at 1200 masl than at 2200 masl. Thus, photo-inhibition is a relevant physiological attribute at high-altitude populations where light is more intense. Photo-inhibition may be overcome if seed can be easily buried in the soil. We discuss the ecological implication of this eco-physiological trait on invasive process of this species. Acknowledgements: ICM-P05-002, PFB -23 and CONICYT. Drought in small streams: a laboratory experiment with invertebrates MARILUAN G.*; ALBARIñO R. and DíAZ VILLANUEVA V. Laboratorio de Limnología INIBIOMA *gusmariluan@crub.uncoma.edu.ar We aimed to analyze the survival of 3 species of invertebrates, common in headwaters of north andean Patagonia, when exposed to an experimentally recreated drought. Larval specimens of the leptophlebid mayfly Meridialaris chiloeense and the limnephilid caddisflies Monocosmoecus sp and Verger capillatus were placed in individual containers with clean fine substrate, food (M. chiloeensis: stones with periphyton, both caddisflies: stones + decaying leaf litter) and filtered stream water, and maintained aerated at 13°C with a 14:10 day-night photoperiod. Every third day water, food and substrate from the containers were renewed and survival of insects and feeding signs were checked. The experiment consisted of a treatment with a 14% reduction in the water level per day (i. e. only wet sediment from day 15) and a control with a constant water level (70mm above substrate). In all cases, four replicates per treatment and species were set. Specimens of V. capillatus were alive in the four containers after 90 days of experiment, all M. chiloeense and Monocosmoecus sp. died before 20 and 50 days respectively. In contrast, invertebrates in the controls were alive longer, and adult emergencies were also registered. This study provides a first approach to assess the vulnerability of aquatic biota to drought in small streams. Further field and laboratory investigations would allow us to understand the ecological effects of such disturbance. Effects of agriculture on the structure of plant-pollinator interaction webs in the Pampas of Argentina MARRERO H.J.; MEDAN D. and TORRETTA J.P.* Facultad de Agronomía de la U.B.A. *hugomarrero@gmail.com Agriculture expansion and intensification is affecting biodiversity worldwide, and is suspected to alter pollination interactions in the Argentine Pampas through loss of habitats used by native plants and insects. We compared network metrics obtained over 5 consecutive months at two continually cultivated plots (C) and two long uncultivated (>20 years) nearby plots (U) in the Inland Pampa, Argentina. On average, cumulated webs supported by U plots were 2.2 times larger than those of C plots, had more links per species (1.5 vs. 1.3), and displayed higher nestedness (0.18 vs. 0.045), but did not appreciably differ in robustness. Our result indicate that agriculture affects plant-pollinator webs inducing loss of mutualistic species and reducing redundancy of interactions, and underline the importance of uncultivated habitats as refuges for organisms excluded from agricultural networks. Ontogenetic changes in tree insect herbivory and foliar traits in dry and wet southern beech Patagonian forests MAZÍA N.* (1); GARIBALDI L. (2); CHANETON E. (3) and KITZBERGER T. (2) (1) Depto. Prod. Vegetal, Facultad de Agronomía (UBA) (2) INIBIOMA–CONICET, Universidad Nacional del Comahue (3) IFEVA, Facultad de Agronomía (UBA) *cmazia@agro.uba.ar As plants pass through successive life stages, marked changes occur in apparency, structural complexity and nutritional quality, which can influence susceptibility to herbivory. Based on different assumptions different models make contrasting predictions about herbivore responses to changes in host traits among age-size classes. Yet, there have been few tests of the effect of ontogeny on herbivory, especially in forests. We examined folivory by different insect guilds on three age-size classes of Nothofagus pumilio trees, in dry and wet forests of northern Patagonia, Argentina. We sampled the canopy of saplings (< 1m tall), juveniles (3-4 m) and adult trees (>10 m), and measured physical and chemical leaf traits for each plant (n = 14). Early in the growing season, leaf damage was higher in saplings and juveniles than in adult trees in both forests, and remained so later in the season in the wet forest. In contrast, in the dry forest, insect damage markedly increased at the end of the season on adult trees, which blurred earlier differences among age classes. There were significant, habitat-specific differences in foliar traits among tree classes, but these could not account for herbivory patterns in either forest. Overall, we found partial support for the hypothesis that insect herbivory declines as trees grow from a deep understorey layer into the upper forest canopy. However, ontogenetic changes in folivory appeared to depend on the forest habitat. Thermal and reproductive responses to harsh environments in Patagonia, Argentina. MEDINA S.M.* and IBARGÜENGOYTÍA N.R. INIBIOMA-CRUB-UNIVERSIDAD NACIONAL DEL COMAHUE *patagoniasubacuatica@yahoo.com.ar In southern temperate ecosystems, environmental temperatures strongly influence the distribution and activity of reptiles and their ability to obtain energy to grow and reproduce. Thermoregulatory activity and the timing of reproductive events influence the aptitude of the species and it is expected that variation among individuals and among species exists in responses to different environmental conditions. We examined ecotypic differences in reproductive and thermal physiology at two latitudes (43° and 46°S) in three lizard species: L. bibronii and L. boulengeri (oviparous), and L. lineomaculatus (viviparous). Body and operative temperatures were measured in the field, and preferred body temperatures were estimated in the laboratory. We calculated the efficiency of thermoregulation and describe the reproductive cycles of males and females of each species. Body temperatures were low and similar among species; however the efficiency of thermoregulation showed that the oviparous species are better thermoregulators than the viviparous L. lineomaculatus. The reproductive cycles of the three species are similar but, because L. lineomaculatus lives at higher latitudes than the oviparous species, the lower temperatures that their eggs experience in the nest could limit development, and consequently constrain the timing of incubation periods and the performance of hatchlings, and their ability to attain and maintain body temperatures appropriate for growth and reproduction. Exotic tree invasion alters community dynamics and ecosystem function in successional pampa grasslands MIRANDA M.I.* and CHANETON E. IFEVA, Facultad de Agronomía, UBA *miranda@ifeva.edu.ar Exotic tree invasions in the Pampas are driving wholesale ecosystem changes from the pre-Columbian perennial tussock grasslands to modern savanna-like grasslands and woodlands. We predicted that tree encroachment in open successional fields would modify herbaceous community composition and functioning, by selecting for species with complementary resource-use patterns. We studied tree invasion gradients in two old fields with contrasting history and dominant woody species (Ulmus pumilia and Gleditsia triacanthos) in the Inland Pampa, Argentina. We focused on four stages of invasion: non-invaded grassland, isolated adult trees, low-density woody patches, and high-density woody patches. We found that light and soil water availability and herbaceous primary productivity decreased across woody invasion gradients, with the impact depending on the amount of basal area accrued by trees. Effects on herbaceous communities were already apparent at intermediate stages of invasion, as we detected a shift in functional composition towards relative dominance by cool-season grasses. The final stages of invasion were characterized by low total herbaceous productivity and a significant decline in topsoil organic carbon. Our findings reveal major ecosystem-level impacts of exotic tree invasion in old-field communities including forage production and carbon storage in soil. Tree-invaded Pampa grasslands constitute a dramatic case of the ongoing emergence of novel ecosystems worldwide. Spatial analysis of ignition point patterns and the probability of fire occurrence in the western area of Neuquén provin MUNDO I.* (1); WIEGAND T. (2) and KITZBERGER T. (3) (1) IANIGLA - CONICET (2) UFZ Leipzig-Halle (3) Laboratorio Ecotono - INIBIOMA - CONICET *iamundo@lab.cricyt.edu.ar The spatial pattern of fires occurrence is an important feature in the fire dynamics studies helping to understand how fire can shape or modify the structure and composition of the vegetation communities at a landscape scale. Our objectives were 1) to characterize the spatial pattern of fire ignitions (855 points) in the western area of Neuquén (1992-2008), 2) to analyze the spatial association of climatic, accident-negligence and arson caused fires to towns and 3) to map fire ignition probabilities based on topographic, climatic, land cover and anthropogenic map variables. Univariate and bivariate point pattern analyses were conducted by means of the O-ring statistic. Maps of ignition probabilities were derived through stepwise logistic regression. The distribution of observed number of ignitions in each land cover type differed significantly from the expected number. The steppe, wetlands, forest plantations and urban areas presented more ignitions than expected. The spatial pattern of total ignitions showed a non homogeneous distribution. A positive interaction between total ignitions and towns was observed at distances shorter than 5 Km. The fire probability model that included all variables reached the best adjustment (AUC:0.854-overall correctness:77.7). Based on the strong relationship between human variables and fire ignitions and considering the expected demographic growth in Neuquén, an increase in the area affected by fire is highly expected during the XXI century. Latitudinal versus local environmental drivers of aquatic macrophyte diversity in Southern Hemisphere calcareous rivers MURPHY K.* (1); TAPIA GRIMALDO J. (1); O'HARE M. (2); DAVIDSON T. (3) and SABBATINI R. (4) (1) University of Glasgow, UK (2) Centre for Ecology & Hydrology, UK (3) University College, London, UK (4) Universidad Nacional del Sur, Argentina *mearnskevin@googlemail.com We use information on vascular aquatic macrophyte occurrence, river water physico-chemistry and catchment information, derived from the literature, pre-existing databases held by collaborators around the world, and primary survey of calcareous (“hard water”) rivers to assess the relative importance of global-scale (latitudinal) factors versus local environmental conditions in driving river macrophyte diversity. Here we present initial results from a subset of Southern Hemisphere calcareous rivers (defined as water >10 mg l-1) lying in the range 10 – 40oS. We used TWINSPAN classification and DCA ordination procedures to analyse data from 112 river sites in Zambia, Botswana, South Africa, Brazil and Argentina, and compared the outcome with analysis of a combined dataset for rivers within the equivalent latitudinal range both north (62 sites from Greece and Portugal) and south of the Equator (in total supporting 262 species). The outcome suggested that latitude was an important driver of river plant community composition and diversity, but significant relationships were also found between macrophyte diversity and local factors such as river pH and conductivity. Influence of altitude, vegetative and floral traits on the plant mating patterns: hypotheses testing using SEM NAULIN P.I.* (1); ARROYO M.T.K. (2); COLE W. (3) and BARRETT S.C.H. (3) (1) IEB, U. de Chile. Fac. Cs. Forestales, U. de Chile (2) IEB, Fac. Ciencias, U. de Chile (3) EEB, University of Toronto, ON, Canada *pnaulin@gmail.com Alpine environments show extreme conditions which could be stressful for plant reproduction. High altitude may decrease pollinator availability, altering mating patterns, and causing increased selfing rates. Several mechanisms may allow plants to compensate for declines in pollinator availability, including increased allocation to reproductive structures to promote pollinator attraction thus increasing outcrossing probability. A. pallida is a self-compatible, protandrous, alpine angiosperm. We studied the relations between flower number, plant size and mating patterns on 80 individuals from 4 populations located along an altitudinal gradient, measuring plant size, flower number and outcrossing rate, based on open-pollinated families. Mating patterns were estimated with allozyme markers by MLTR. We used structural equation models (SEM) to elucidate which morphological variables were most important for outcrossing rates. We found that plant size was reduced at higher altitudes, whereas flower number was not significantly different between lower and higher populations. There was no clear relationship between individual outcrossing rates and altitude. SEMs indicated that altitude reduced plant size and flower number, which in turn showed little contribution to the variation in outcrossing rate. Altitude did not have a large effect on the outcrossing rate of populations even when indirect effects are included. Funding: Becario CONICYT, FONDECYT 1085013, ICM P02-005. Reproductive Biology of Tropidurus torquatus (Squamata: Tropiduridae) in Corrientes, Argentina ORTIZ M.A.* (1) and ÁLVAREZ B.B. (2) (1) UNIVERSIDAD NACIONAL DEL NORDESTE-FACULTAD DE CIENCIAS EXACTAS NATURALES Y AGRIMENSURA (2) UNIVERSIDAD NACIONAL DEL NORDESTE-FACULTAD *ortizmartin143@yahoo.com.ar We analyzed the reproductive activity of a population of Tropidurus torquatus from northeastern Argentina in order to notice if environmental differences from different part of its distribution result in variation in its reproductive traits. The study was carried out in Corrientes locality, belonging to District Oriental of Chaco Province, Argentina. Collections were made between December 2007 and November 2009. The male reproductive activity was determined through histology of gonads and epididymis and using gonadosomatic indexes. We determined reproductive cycle of females on the base of the presence of vitellogenic follicles, oviductal eggs, and corpora lutea. Males contained sperm in seminiferous tubules year-round, but the maximum values of testicular length were in September-October. Vitellogenic females were found from July to December and oviductal eggs in September, October, December, and January pointing out that males and females have synchronic reproductive activity. We found that the reproductive cycle of T. torquatus from Corrientes was similar to a Cerrado population (Brazil) but the clutch size and minimum size at sexual maturity are higher than in the coastal populations of the Atlantic Forest biome (Brazil), probably because variations in the local environmental conditions affect positively growth rates of the Chaco Province population resulting in a higher average body size of females. Exotic species influencing native parasites: a cause for concern? PATERSON R.* (1); RAUQUE C. (2); TOWNSEND C. (1); POULIN R. (1) and TOMPKINS D. (3) (1) University of Otago, New Zealand (2) Laboratorio de Parasitología, INIBIOMA, CONICET-U (3) Landcare Research, New Zealand *patra374@student.otago.ac.nz Exotic species can have deleterious effects on native biodiversity, particularly involving predation and competition, but have been increasingly implicated in disease impacts on native species. Recent studies have demonstrated strong effects of parasite spillover, whereby native species are exposed to new parasites from exotic hosts. However, exotic species may also acquire native parasites and have the potential to alter native parasite dynamics by acting as infection reservoirs (spillback) or sinks (dilution) or cause no change. Our research has focused on native parasites of native and exotic freshwater fish in New Zealand and Argentina. We aimed to determine how the presence of exotic hosts influences the dynamics of native fish parasites. We conducted a combination of field surveys and laboratory experiments involving native and exotic hosts, and constructed dynamic community models to examine the influence of exotic species. We have demonstrated two of the potential outcomes of exotic species acquisition of native parasites and have established the main factors that determine whether parasite dynamics are modified. Host competency for native parasites was essential in determining the occurrence of spillback and dilution, but other factors (e.g. host density) may alter the influence of exotic species on disease in native fish. Our research highlights a seldom-recognised mechanism involving host-parasite dynamics by which exotic introductions can impact native species. Warning against generalizations in modelling animal movement: the case of Dromiciops gliroides in northern Chiloé PIAZZON DE HARO M.A.* (1); R. LARRINAGA A. (1); CELIZ DIEZ J.L. (2) and SANTAMARíA L. (3) (1) IMEDEA-CSIC (2) Pontificia Universidad Católica de Chile (3) IMEDEA- CSIC *martinpiazzon@gmail.com We used a multidimensional approach to identify the ecological niche of the arboreal marsupial Dromiciops gliroides. Habitat characteristics (habitat structure and resource availability) were mapped over 16 ha of forest, using a 20x20 m grid for structural variables and epiphyte-fruit availability (N=440) and a 60x60 grid for insects (N=50). Habitat utilization was based on the relocations of 16 individuals, captured within the mapped area and radio-tracked at hourly intervals during 8 nights. We used the k-select method, which is based on the congruence between habitat availability and use within the home range of each individual, to identify the variables responsible for habitat selection at individual level. We did not find a common pattern of habitat use across all individuals (e.g. three orthogonal axes were needed to reach 65% of the total variance). However, groupings in the two-dimensional plot (first two axes) showed three distinct groups of individuals, corresponding to animals exploiting three structurally-different habitats: old-growth forest, young/secondary forest and open areas (gaps). Each of these habitat units seems to present specific combinations of resources, as shown by the association between their habitat-structure and resource-availability variables in the k-select plot. Our result suggest that efforts to “force” a general habitat-selection model to all individuals in a given population can lead to misleading results. Effect of harvester ants (Pogonomyrmex spp.) on the soil seed bank near their nests in the Monte desert, Argentina PIRK G.I.* (1) and LOPEZ DE CASENAVE J. (2) (1) Laboratorio Ecotono, INIBIOMA, CONICET-UNCOMA (2) ECODES, DEGE, Universidad de Buenos Aires *pirk@crub.uncoma.edu.ar Granivorous animals can have a significant impact on soil seed abundance. As central-place foragers, harvester ants may reduce seed reserves more drastically near their nests. In the Monte desert, Argentina, ants of the genus Pogonomyrmex show relatively high seed removal rates during their foraging season (late spring-early autumn) and concentrate their consumption on a few grass species. The aim of this study was to quantify soil seed abundance of the most consumed species at different distances from the nest along the foraging season. Soil seed abundance was measured in bare soil and litter on three occasions (October, December and April). In October, no distance gradient in seed abundance was detected, probably because of the low level of seed consumption at the beginning of the season. In December Stipa ichu seeds were less abundant in the litter close to the nest entrance. These seeds are the first grass seeds to be produced and ants usually consume them when other grass seeds are still scarce. In April, seed abundance in the litter was lower near the nest, probably as a consequence of the high consumption from midsummer on. The lack of an effect in bare soil could be due to the lower seed harvest of ants in this substrate or to the high horizontal redistribution of seeds in exposed sites. This study suggests that the presence of Pogonomyrmex colonies increases the heterogeneity of the soil seed bank in the Monte desert, eventually affecting vegetation patterns. Sapstain fungi on native trees of Patagonia, Argentina RAJCHENBERG M.*; GRESLEBIN A. and DE ERRASTI A. Centro Forestal CIEFAP, Esquel, Argentina *mrajchenberg@ciefap.org.ar Sapstain is a black or bluish discoloration of sapwood caused by the presence of pigmented fungal hyphae. They produce a cosmetic damage to wood and an economic loss to the forest industry. Most of these organisms are ubiquitous but may also display particular host or biogeographic relationships. This presentation summarizes the first results of a 5 year survey project that aims to establish the etiology and damage caused to native timbers from the Patagonian Andes. Sawmills and native forests of Chubut, Rio Negro and Neuquén were surveyed in autumn and spring 2009, and 195 stained wood samples were collected and processed in order to isolate the causal organisms. Pesotum sp. was obtained from Fitzroya cupressoides and Ceratocystis moniliformis s.l. was isolated from Nothofagus pumilio. A strain obtained from Nothofagus obliqua was identified as Ophiostoma sparciannulatum nom. prov., a novel species not formally described so far. Dothiorella sarmentorum (Botryosphaeriaceae, Ascomycota) is responsible for a severe sapstain in Austrocedrus chilensis. All species were essayed in vitro in order to characterize their staining capabilities. Results and perspectives are discussed. Estimating population density and home range of Dromiciops gliroides from spatial capture-recapture data RIVAROLA M.D.* (1); AMICO G.C. (2); CARLO T. (3) and MORALES J.M. (2) (1) Universidad Nacional del Comahue (2) Lab. Ecotono, INIBIOMA, CONICET Univ. Nac. Comahue (3) Penn State University *rivarola.daniela@gmail.com Dromiciops gliroides is an arboreal and nocturnal marsupial endemic to the northern portion of the temperate forests in southern South America associated with Nothofagus forest. We studied the population density and home range of D. gliroides in Llao-Llao Municipal Park, Bariloche, Argentina. The study was conducted during the summer of 2009. Two square grids were established 150 m apart. Each grid consisted of 25 live-traps spaced at 10 m intervals. Traps were run over four consecutive nights each month. Captured marsupials were fitted whit PIT-tags before release at the point of capture. A total of 72 individuals were caught out of 152 captures. Bayesian analysis was implemented using data augmentation method in WinBUGS and MCMC were used to estimate posterior probabilities. We estimated that capture probability was three times larger for juveniles than adults even though the ratio of juveniles to adults was estimated as 41/59. Capture increased with weight but did not vary with sex. Finally, a spatially explicit capture model estimated population density as 21 Ind/ha, and the average home range was 1.44 ha. These estimates are based on assuming fixed activity centers and exposure to traps as a function of animal movements within their home ranges rather than ad-hock guesses about sampled area. Home range sizes are similar to those obtained through telemetry studies both in the study area and in Chile. Thus, this rare and endangered marsupial can be locally abundant. Nothofagus pumilio dieback in northern Patagonia, Argentina: The influence of climate variations RODRIGUEZ CATóN M.*; CALI S. and VILLALBA R. Instituto Argentino de Nivología, GlaciologIANIGLA *mrodriguez@mendoza-conicet.gov.ar The aim of this study is to determine the climatic influences on Nothofagus pumilio forest dieback in Patagonia. Two increment cores were collected from 50 individuals at Taraya (39°06´S, 71°09´W) and Paso Córdoba (40°53´S, 70°50´W). Tree positions were recorded to evaluate changes in tree growth related to endogenous dynamics. Crown mortality, dead bark at breast height, Mysodendron abundance, insect and woodpecker damages were also quantified. Samples were processed using traditional dendrochronological techniques. Both visual and computer-assisted cross dating were used to date the cores. Ring widths were standardized using a horizontal line through the mean. Dominant patterns of tree growth were identified using principal component analysis. Similar patterns were observed in both sites. An old and a young cohort of trees were identified at the Taraya stand. Although most old trees show a steady reduction in tree growth since the 1940s, a few dominant trees increase growth in the past decades. The cohort of young trees has a positive growing trend and no dieback. Most large trees in Paso Córdoba show a reduction in radial growth from early 1940s. A second group increased the growth rate in the 1940s and stabilized during the recent 6 decades. The release of resources by the declining trees has accelerated the rate of growth of the remaining trees in the stand. At both sites, major changes in growth pattern are related to extreme drought events as those recorded in 1943-44. High Endomycorrhizae diversity among invading Pseudotsuga menziesii in Nothofagus spp. forests from Patagonia, Argentina SALGADO SALOMóN M.E.* (1); RAJCHENBERG M. (2) and BARROETAVEñA C. (2) (1) UNPSJB, CONICET (2) UNPSJB, CIEFAP, CONICET *mesalgadosalomon@gmail.com Pseudotsuga menziesii is one of the most widely planted conifers in the Patagonian Andes region of Argentina, and its invading characteristics have been widely reported. Invasion would be strongly conditioned by its autoecology, environmental variables and the establishment of shared mycorrhizal associations. We studied the morphology and abundance of endomycorrhizae present in P. menziesii seedlings growing in 4 Nothofagus-P. menziesii matrices. One transect along the effective recruitment area was established at each site in order to wrench 25 seedlings along with a soil sample. VAM colonization varied between 25-60%, with different proportions of Arum and Paris types between sites, but with a constant presence of dark-septate endophytes. The four sites showed high abundance and morphological VAM diversity (vesicules size, presence/absence of arbuscules, intra- vs. extracellular hyphae, microsclerotia, DSE structures) and mycorrhization percentage. These variations were correlated to site and soil parameters: positively associated with soil OM, total N and electrical conductivity, and negatively with temperature, precipitation and pH. Patterns of cone production, seed predation and seedling establishment in the large-seeded Araucaria araucana SANGUINETTI J.* (1) and KITZBERGER T. (2) (1) Parque Nacional Lanín - APN (2) INIBIOMA-CONICET y Laboratorio Ecotono, CRUB. *sanguinetti.javier@gmail.com Spatio-temporal patterns of cone production, seed predation and seedling establishment were studied in Araucaria araucana. With cone production and seed gathering data we covered up to 18 years from 12 sites in an area of more than 7600 km2 in Neuquén Province (Argentina). Predation, seed survival and seedling establishment were measured during 2004-2008 at different microsites from 11 isolated trees in A. araucana and Nothofagus pumilio or N. antarctica mixed forest, where native rodents and exotic wild boar are abundant. Long term regeneration was also studied. A. araucana showed an environmentally triggered, intermittent, moderately fluctuating and highly regional synchronous masting. Wild boars ate up to 45 % of available seeds on a 13-day period vs. 30 to 60% eaten by rodents, and seem to affect the individual fitness of mother trees. Rodent predation was high at dense vegetation, while wild boar predation was moderate at poorly vegetated microsites. A. araucana showed a pulse of seedling establishment, synchronized among trees and associated with masting where a 5 fold increase on seed survivorship occurred. Under Chusquea bamboo cover seedling regeneration was strongly inhibited by granivory. We conclude that A. araucana regeneration seems to be mainly controlled by seed production, but granivory modulate the intensity of seedling establishment. Pollination efficiency and predator satiation may have shaped the reproductive strategy of this unique tree. Effects of the exotic willow (Salix fragilis ) on benthic invertebrate communities in streams of Patagonia, Argentina. SERRA M.N.* (1); ALBARIñO R. (2) and DIAZ VILLANUEVA V. (2) (1) Universidad Nacional del Comahue - Centro Regional Bariloche (2) Universidad Nacional del Comahue - Lab Limnologia *marianoelserra@yahoo.com.ar We conducted a field survey and leaf litterbag experiments in three streams of the Nahuel Huapi National Park to study the consequences of the invasive Salix fragilis on aquatic invertebrate communities. In each Stream, we selected two Sites (one dominated by the native shrub chacay, Discaria trinervis, and another by willow trees). The study reaches were similar in water temperature, conductivity and stream depth but differed significantly in channel width and discharge. Leaf litter breakdown rates (k) for willow and chacay leaves were obtained from initial and final (30 days) leaf masses at each site, assuming an exponential decay model. Benthic invertebrate composition was analized in litterbags and also from Surber samples collected at each site. Differences in k values for willow and chacay leaflitter were not consistent among Streams and Sites (3-way ANOVA), being significantly higher for chacay only in two sites (one with native and other with exotic riparian plants). Abundance and diversity (H´ index) of invertebrates colonizing litterbags were higher in sites with chacay vegetation. However, H´ of the whole benthic invertebrate community did not differ among Sites and Streams. In addition, community abundance varied between Sites differently in each Stream (2-way ANOVA). Our results suggest that willow invading the study streams had no consistent effects on benthic invertebrate communities. Impact of forest management on Misodendrum and Usnea productivity in Nothofagus forests in Tierra del Fuego SOLER ESTEBAN R.*; MARTíNEZ PASTUR G. and LENCINAS M.V. Centro Austral de Investigaciones Científicas *rosinas@cadic.gov.ar Misodendrum (M) is endemic of subantartic forests while Usnea (U) is widely distributed. Both are characteristic of Nothofagus forests in Patagonia, where harvesting could affect those populations. The aim was monthly quantify biomass fall of U and M during 2-3 years in primary-P, secondary-J and managed forests (dispersed-D and aggregated-A retention, and silvopastoral-S) of N. pumilio (lenga) and N. antarctica (ñire) forests. Ten biomass traps were placed in 21 stands and data was analyzed with ANOVAs. In lenga forests, U and M biomass varied among treatments (F=14.9 p<0.01, F= 8.8 p<0.01) and years (F=48.3 p<0.01, F=49.5 p<0.01). Only M showed monthly diferences (F=15.6 p<0.01). Largest biomass of U was in P (31.1 kg.ha-1.year-1) but M was in A (73.8 kg.ha-1.year-1). When biomass production was standardized with basal area, there was greater production of U in P and A than in D, while M was greatest in harvested stands. In ñire forests, only the U biomass varied among treatments (F=20.8 p<0.01) and years (F=27.7 p<0.01), being higher in P and S (40.5 kg.ha-1.year-1). There were monthly variations for U (F= 4.7 p<0.01) and M biomass (F= 12.5 p<0.01). Monthly, the biomass fall was higher at the beginning of growing season in lenga (U: 3.4 kg.ha-1, M: 7.1 kg.ha-1) and ñire forests (U: 5.8 kg.ha-1, M: 51.1 kg.ha-1). Mature forests present more Usnea biomass than harvested or secondary forests; while Misodendrum biomass increase with disturbance degree in N. pumilio stands.. Rock outcrops enhances plant diversity in Patagonian landscape SPEZIALE K.* and EZCURRA C. Universidad Nacional del Comahue-INIBIOMA-CONICET *kspeziale@crub.uncoma.edu.ar Rock outcrops usually support unique communities also acting as refuge for species that cannot survive in the surroundings due to overgrazing, fire or climate change among other disturbs. We studied plant communities associated to 50 outcrops along a diverse longitudinal gradient from shrubland to steppe habitats in north-western Patagonia. We recorded every plant species in each outcrop and mounted a temperature and humidity sensor (north and south face). We also characterized the outcrops respect to their morphological variables. We compared species composition and richness within outcrops (north vs. south face), between outcrops and between each outcrop and its surrounding matrix. Correspondence analysis separated shrubland, steppe and outcrop plots. Within outcrops composition of north faces was different from those of the south face. Differences in species composition and richness were related to microsite variables. Our results suggest that rock outcrops could be acting as refuges for species that cannot be found in the surrounding matrix. In this way outcrops could be enhancing biodiversity in north-western Patagonia. Co-existing native and introduced millipede (Diplopoda) species in native forests in Auckland, New Zealand TOMLINSON A.* (1); WARDLE D. (2) and BEGGS J. (1) (1) University of Auckland (2) Swedish University of Agricultural Sciences, Umea *atom006@aucklanduni.ac.nz A critical issue in conservation ecology is quantifying the ecological impacts of invasive species on native ecosystems. Decomposition and nutrient cycling are key ecosystem functions, hence the importance of quantifying the impact of introduced detritivores on decomposition rates and native decomposer communities. New Zealand has a diverse native litter fauna with high levels of endemism, which has been augmented and possibly displaced by naturalized introduced invertebrates. Millipedes (Diplopoda) were selected as the focal group of this study because of their ecological importance in fragmenting litter in the early stages of decomposition. New Zealand's native millipede fauna is highly diverse and there are at least thirteen introduced species. Litter invertebrates were sampled in native forest fragments to determine the community composition of co-existing species of native and introduced millipedes. Laboratory trials were conducted with native and introduced millipedes to quantify litter preferences and consumption to determine: (1) the per capita impact on the litter resource, and (2) the degree of overlap in resource and habitat requirements of different species. There was a high level of co-existence of native and introduced millipedes at many sites. High nutrient litters were preferred by most millipede species, confirming the findings of other studies, and suggesting that introduced millipedes may compete with native species for litter resources. Studies on the reproductive biology of Nothofagus species TORRES C.D.* (1); PUNTIERI J.G. (2) and STECCONI M. (1) INIBIOMA (2) INIBIOMA- Universidad Nacional de Río Negro *cristiantorres@crub.uncoma.edu.ar In monoecious wind-pollinated species, like Nothofagus, the distribution of flowers in time and space is relevant to facilitate pollen flux and avoid selfing (in self-incompatible species). For some Nothofagus species the production of viable seeds exhibits notable between-year fluctuations, being low in most years. The reasons for these variations are unknown. We hypothesized that deficient pollination may have a significant effect on low seed sets in these species. The aim of this study is to deal with this issue through the application of manual pollinations and the study of the distributions of pistillate and staminate flowers. We performed manual intra-individual and intra- and inter-specific pollinations in nursery N. nervosa and N. obliqua trees. In a natural population of N. nervosa and N. obliqua we compared the production of viable seeds between natural and manually pollinated flowers and assessed the role of flower position on the tree on seed set. The manual pollination technique resulted useful for small-scale seed production. The study of the phenological stages of flowering shoots allowed us to conclude that it is highly probable that pistillate and staminate flowers within a shoot have overlapping antheses. Preliminary data about compatibility relationships between Nothofagus species and inter-specific hybrids also resulted from this study. In N. obliqua, the proportion of viable seeds depended on the position of the flowering shoot in the main branch. Florivory by the bee Megachile distinguenda and reproductive ecology of Chaetanthera renifolia in Central Chilean Andes TORRES-DIAZ C.* (1); GIANOLI E. (2); GOMEZ-GONZALEZ S. (1); STOTZ-CANALES G. (1) and TORRES-MORALES P. (1) (1) Universidad de Concepcion (2) Universidad de Concepcion, Universidad La Serena *critorre@udec.cl Flower size has been traditionally interpreted as a product of pollinator-mediated selection. However, recent studies suggest that floral traits may represent an adaptive compromise between selection caused by mutualists (pollinators) and antagonists, such as floral herbivores. Our aim was to determine whether floral herbivory by the native leaf cutter bee Megachile distinguenda may affect flower head size evolution in Chaetanthera renifolia (Asteraceae), a perennial herb endemic to the Andes of central Chile. To this end, we evaluated (1) the relationship between C. renifolia flower head size and its attraction to the bee M. distinguenda, and (2) the indirect effects of floral damage on the attractiveness of C. renifolia to insect pollinators and the ensuing female reproductive success. Florivory on Chaetanthera was simulated by clipping ligulate petals with a scissor (50% ligulate petals). A total of 60 plants were randomly assigned to control (unclipped) and damage groups. We found that pollinator visitation rates and female reproductive success did not differ between clipped and unclipped plants. Although M. distinguenda preferentially cuts larger floral heads, and hence could exert a selective pressure against large flowers, pollinators seemingly do not prefer to visit larger flowers. Consequently, the conflicting selection hypothesis could not be evaluated in this system. Funded by FONDECYT-3090020. Beta diversity patterns and their contribution to landscape and regional floristic diversity in Western Australia VAN ETTEN E.* Edith Cowan University *e.van_etten@ecu.edu.au The southern continents have several well-known plant diversity hotspots, including the south-west of Western Australia. Other areas of this state are renowned for considerable richness at genus level (eg the Pilbara has 100 taxa of Acacia; the Goldfields are rich in Eucalyptus). Such richness patterns have typically been explained in terms of high local species richness (alpha diversity) in combination with strong sorting of species to landform/soil patterns (main type of species turnover or beta diversity). However the contribution of within-landform/community turnover of species may be under-appreciated, particularly in transitional rainfall zones where speciation during the Quaternary Period is likely to have resulted in relatively restricted plant species distributions amongst certain taxa. In this paper, I present some reanalyses of field data I have collected over many years in the Pilbara, Yalgoo and Coolgardie bioregions of Western Australia which aims to identify spatial structure independent of known landform/soil and climatic patterns. Species turnover within landforms was a feature of all landforms in all regions examined, but was highest on uplands and areas of outcropping even in topographically subdued regions. In comparison to a few other regions examined using similar techniques, within-landform plant species turnover appears to be substantial in many Western Australian regions, and contributes significantly to regional level richness (gamma diversity). Ground beetles assemblages (Coleoptera, Carabidae) along elevational gradients in NW Patagonia WERENKRAUT V.* and SPEZIALE K.L. INIBIOMA-Universidad Nacional del Comahue *vicwkt@gmail.com The study of species distribution along environmental gradients can shed light on the factors governing and maintaining species diversity, and provide useful information for species conservation. In particular, altitudinal gradients offer a good scenario for these studies given they provide significant changes in environmental variables within relatively short distances. We examined the variation in ground beetles community composition along five altitudinal transects ranging from 800 to 2000 m.a.s.l., within Nahuel Huapi National Park, Patagonia, Argentina. Sampling plots were placed every 100 m of altitude from the base to the summit of each mountain. We used pitfall traps to sample insects during four sampling periods spread along two years. Biotic and abiotic environmental variables were also recorded. We used canonical correspondence analysis to determine the relationship between beetles assemblage structure and the environmental variables. We collected 6207 carabid beetles representing 21 species. The analysis showed three main assemblages of beetles. A small group of high altitude species was associated with open habitats and low temperatures. A second group was related to an increase in tree cover and minimum temperature, and was repelled by the presence of carnivorous ants. The remaining species were positively related to plant species richness. Thus, both biotic and abiotic factors affect carabid species distributions along elevational gradients in Patagonia. Biogeography Using cartography to understand the historical distribution of Araucaria araucana AAGESEN D.* State University of New York *aagesen@geneseo.edu Araucaria araucana is a long-lived conifer endemic to the Andes of central Chile and Argentina. Small stands also exist in the Nahuelbuta Mountains near the Chilean coast. The species is a valuable resource to the region's indigenous inhabitants, and in the past it was coveted by the timber industry. Mismanagement of Araucaria araucana has led to its depletion throughout much of its natural range, but changes are difficult to quantify. Historical maps depicting the geographic extent of Araucaria araucana offer some insight into this problem. This poster displays a series of maps of Araucaria araucana’s growth range. The maps were collected during archival and library searches in Chile and Argentina. They span nearly 100 years -- from 1897 to 1992. The maps are useful in understanding the temporal and spatial dynamics of Araucaria araucana, but to make meaningful comparisons it is necessary to understand issues related to data classification, sampling, cartographic accuracy and map scale. On their own, the maps are of limited value. They can be extremely useful, however, when used with field observations and measurements, aerial and landscape photographs, historical text documents, oral histories, ethnohistorical and ethnobotanical information, archaeological evidence, and the palynological and dendrochronological records. This underscores the value of incorporating a multidisciplinary approach when investigating the historical distribution of forest species and ecosystems. Comparative phylogeography of two keystone species: a mistletoe and a marsupial AMICO G.* and VIDAL-RUSSELL R. Lab Ecotono, INIBIOMA (CONICET- Unv. Nac. Comahue) *guilleamico@gmail.com Mistletoes are aerial parasitic plants that are intimately dependent on hosts for water and nutrients. Most of these plants depend obligatory on vectors for transporting seeds form the parent plant to branches of a host plant; without dispersal most mistletoes will not complete their life cycle. Hence, complex associations with animals that disperse their seeds evolved. Mistletoes can be keystone species that determine community structure and diversity. The mistletoe Tristerix corymbusus (Loranthaceae) has a unique animal as seed disperser along all the temperate forest of southern South America. Contrary to what is found in most mistletoe, dispersal by bird, T. corymbusus is actually dispersed by the endemic marsupial Dromiciops gliroides (Microbiotheriidae). This marsupial is also considered as a keystone species because it disperses several plant species in the forest. We did a comparative phylogeographic study of the marsupial and the mistletoe along the overlapping distribution of these closely associated species. Both species have some haplotypes with a wide distribution while others are only found in restricted areas. There are some localities where both species have unique derivate haplotypes, which suggest they share glacial refugia. Given the high dependence in this two species and their important role in the community, it can be considered that places proposed as refugia for the mistletoe and marsupial were also refugia for other plants in the Andean forest. Origin and diversification of the leafy hepaticae: insights from the phylogeny of the Lepidoziaceae. COOPER E.D.* (1); BROWN E.A. (2) and HENWOOD M.J. (1) (1) School of Biological Sciences University of Sydney (2) National Herbarium of New South Wales *endymion.cooper@bio.usyd.edu.au Despite an increasing body of literature indicating that long distance dispersal is important in shaping plant distributions, the “out of Gondwana” hypothesis of leafy liverwort origins remains untested. The main difficulty is a lack of robust phylogenetic hypotheses for southern clades of Jungermanniidae. The Lepidoziaceae is a speciose and morphologically diverse family with a predominantly southern distribution and provides an excellent model for testing biogeographic and evolutionary hypotheses in leafy liverworts. Morphological and molecular evidence support its monophylly but the phylogeny is unresolved and is possibly incongruent with the current classification. To address this problem we combined 7 chloroplast, 1 nuclear and 2 mitochondrial markers to resolve the phylogeny of the Lepidoziaceae. We recovered a strongly supported monophyletic Lepidoziaceae. The phylogeny, however, is incongruent with the internal classification and subsequent taxonomic realignment is required. For example, Lepidozioideae are polyphyletic, as are two of its five constituent genera (Kurzia and Telaranea). Biogeographic hypotheses were addressed by inferring divergence times from a subset of chloroplast markers, using a Bayesian relaxed clock approach with fossil age constraints. Our results support an early cretaceous origin for the family and a minimum age of 80 million years for the Lepidozioideae s.str.. These results do not contradict a Gondwanan origin for the family. Discoleus Breure, 1978: is there a pre-Gondwanan ancient stock of Orthalicidae? (Mollusca, Stylommatophora) CUEZZO M.G.* (1); VALDOVINOS C. (2) and BREURE A.S.H. (3) (1) CONICET-Universidad Nacional de Tucumán, Argentina (2) Universidad de Concepción, Chile (3) National Museum of Natural History, The Netherlans *mcuezzo@unt.edu.ar Discoleus breure is an endemic genus of southern South America. The distributional areas of this genus are the most septentrional of Orthalicidae in Argentina. Plectostylus, from Chile was believed to be its sister group and Bothriembryon of Australia was sister group of the former clade (Breure, 1979). Orthalicidae was distributed in Australia and America but it was presumed to be of Gondwanan origin (Solem, 1978). The recent inclusion of Prestonella of South Africa in this family confirmed the Gondwanan distribution of Orthalicidae. We provide here a taxonomic revision of Discoleus, a presumed component of the ancient stock of the Orthalicidae, and a hypothesis of relationships with its related genera. Discoleus is diagnosed by having a vas deferens embedded in the phallic complex, lack of a penial sheath, length of bursa copulatrix duct exceeding the spermoviduct and secondary ureter open. Although Discoleus has been previously classified in Bostryx, they are similar to Bostryx mainly by shell morphology. The genitalia present several differences mainly concerned to the vas deferens in relation with the penial complex and the penial sheath. Preliminary cladistic analysis showed that Discoleus, Plectostylus, Prestonella and Bothriembryon conforms a monophyletic clade supported by three synapomorphies that have good Bremer support score. Herbert & Mitchell (2009) hypothesis on the Gondwanan prefragmentation stock is tested and discussed. Biogeographic patterns of southern South America: multivariate analyses based on plant and animal distributions DONATO M.* (1); POSADAS P. (1); ORTIZ-JAUREGUIZAR E. (1); KATINAS L. (2); SANCHO G. (2); GROSSI M. (3) and CRISCI J.V. (4) (1) LASBE, Museo de La Plata (2) División Plantas Vasculares, Museo de La Plata (3) División Plantas Vasculares, Museo de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina (4) Laboratorio de Sistemática y Biologia Evolutiva (LASBE), Museo de La Plata, Paseodel Bosque s/n, 1900 La Plata, Argentina *mdonato@fcnym.unlp.edu.ar The purpose of this study is to investigate similarity patterns of the biogeographic districts of Cabrera & Willink’s biogeographic schemes (1973, OEA Monographs n°13) of southern South America.Cluster (CA) and Non-metric multidimensional scaling (NMDS) were applied to analyze the regional diversity patterns. The 11 districts belonging to the Patagonian and Subantarctic biogeographic provinces occurring in southern South America were considered as units. Similarity was established based on Asteraceae (147 spp.), Curculionidae (315 spp.) and Chironomidae (155 spp.).The results obtained by CA and NMDS are similar. CA shows the following similarity associations: ((Magellanic Moorland, Islas Malvinas) (((Fuegian, Magellanic Forest) (Maule Valdivian Forest)) (Subandean (((Occidental Central) San Jorge Gulf) Payunia)))), cophenetic coefficient value= 0.8981. The phenogram exhibits similarity indexes ranging from 0.31169 in the highest association (Occidental and Central Patagonian districts) to 0.027778 in the lower asssociation (Magellanic Moorland, Islas Malvinas). The associations resulting from our analysis do not reconstruct the major biogeographic provinces to which the districts belong to. Remarkably, the Fuegian district is associated to Subantarctic districts instead of the Patagonian ones. Tree–growth responses across environmental gradients in northwestern Argentina: relationships from dendrochronology view FERRERO M.E.* and VILLALBA R. Dpto Dendrocronología, IANIGLA, CCT-Mendoza *mferrero@mendoza-conicet.gov.ar In subtropical northwestern Argentina, forests develop from xeric environments in the lowlands through different mesic formations to humid and cold forests at the Yungas treeline. Tree–ring chronologies covering most of environments in this region (22–28° S; 64–65.30° W) were analyzed: 10 chronologies of Juglans australis, 6 Cedrela lilloi, 3 Alnus acuminata and 1 Schinopsis lorentzii. Chronologies were compared with climatic records to determine the factors influencing tree growth. Cluster analyses were conducted to group the chronologies according to their degree of association, which were also evaluated using Pearson correlation coefficient.Cluster analysis separates low (Schinopsis–Juglans) from high–elevation chronologies. Within higher sites cluster discriminate by species: Cedrela and Alnus chronologies form an independent group from the Juglans ones. At species level, subgroups are arranged according to similarities in climate responses; for Juglans, two groups related to temperature and precipitation sensitive sites were recorded. For Cedrela and Alnus, sites were grouped according to water availability.Results suggest that climate is the main factor controlling tree growth at regional scale. In mesic environments, differences in tree–ring patterns are related to the “climatic window” of each species which results in different responses to climate. Discovering the Ice Age through seaweed FRASER C.*; SPENCER H. and WATERS J. University of Otago *ceridwen.fraser@gmail.com Seaweed DNA may hold key clues to the severity and biological impacts of historic climate change. Our phylogeographic analyses of a widespread Southern Hemisphere kelp species (Durvillaea antarctica) revealed startling contrasts in genetic diversity in high- versus low-latitude regions. High genetic diversity in northern regions, versus near-negligible diversity further south, suggests that the species only recently recolonised higher latitudes. We propose that sea ice at the Last Glacial Maximum (LGM) was the primary factor responsible for extirpating this kelp from many of the subantarctic islands, and that Antarctic sea ice was therefore considerably more extensive at the LGM than previous studies have estimated. Similarly, along the Chilean coast our bull kelp results indicate postglacial recolonisation of much of the southern Patagonian coastline. These conclusions have important implications for our understanding of biological responses to climate change in the Southern Hemisphere. Our ongoing research aims to use phylogeographic analysis of a wider range of macroalgal species (both ice-sensitive and ice-resilient intertidal taxa) throughout the Southern Ocean to assess 1) whether LGM sea ice indeed extended further north than previously believed, and 2) the ecological and evolutionary impacts of historic ice scour on shallow marine intertidal ecosystems in the high latitudes of the Southern Hemisphere. Origin of the family Hyriidae (Bivalvia): South America, New Zealand, or Australia? FUENTEALBA C.* (1); GUZMáN B. (1) and REID B. (2) (1) Universidad de Concepcion (2) Centro de Investigación en Ecosistemas de la Patag *carmen.fuentealba@gmail.com; The origin of the family Hyriidae in South America has been difficult to determine. Early work suggested a North American origin, dispersing southward during the early Tertiary, simultaneous to the first mammals that populated Patagonia. This dispersal had a unique orientation given that southern fauna never reached North America. While the fossil record provides evidence of Hyriidae in Texas and Pennsylvania since the Triassic, there are no current records for this family in North America. Studies of the larval stage (glochidia) of South American Hyriidae suggest a close relationship to the Australian genera Hyridella and Velesunio. Various authors have postulated that an ancestral form of Hyriidae arrived in Australia from Southeast Asia, or via an alternative dispersal route by way of Antarctica. Recent molecular phylogenetic reconstruction has provided evidence of a close relationship between South American and New Zealand fauna, supporting the hypothesis of a Gondwana origin. We conducted an analysis of the family Hyriidae based on maximum parsimony and maximum similarity of the Cytochrome Oxidase I gene. Our results support a Gondwana origin, revealing furthermore a closer relationship between the Hyriid fauna of South America and Australia than to New Zealand. Cladistics and predictive distribution modelling provide insights into the evolution of Neoporteria (Cactaceae) GUERRERO P.C.* (1); WALTER H.E. (2) and BUSTAMANTE R.O. (1) (1) Instituto de Ecología y Biodiversidad, U Chile (2) The EXSIS Project *pablo.c.guerrero@gmail.com The classification of the Eriosyce subgen Neoporteria and the role of allopatry/simpatry in the diversification of the group were studied by using cladistic and predictive distribution modelling methods. The analyses placed E. chilensis basal within the Neoporteria clade and suggested a further broadening of the group by including E. taltalensis var. taltalensis, formerly considered a member of subsection Horridocactus. The broad concept of E. subgibbosa sensu Kattermann (comprising seven infraspecific taxa), was rejected by our results, as four of its subspecies and one variety were separated from the nominal subspecies and placed in different subclades. A gradual specialization of the Neoporteria flower towards an ornithophyllous syndrome was observed in the more derived taxa. Finally, our results corroborated changes in subsections Chileosyce and Neoporteria proposed by various authors and suggested further modifications within Neoporteria. The analyses of the degree of geographic overlap of the predicted distributions showed low levels of overlap between the sister taxa, indicating that evolutionary divergence is mainly caused by an allopatric process associated to climatic tolerances. Acknowledgements: ICM P05-002 - PFB -23 and Doctoral fellowship, CONICYT. Preformation, neoformation and bud structure in species of Proteaceae from northern Patagonia MAGNIN N.A.* (1); GROSFELD J.E. (1) and BARTHéLéMY D. (2) (1) Universidad Nacional del Comahue (CRUB) (2) UMR AMAP, Montpellier France *amarumagnin@hotmail.com Preformation and neformation in woody species are processes associated with the vigour of shoots which respond to endogenous and environmental factors. For four species of the family Proteaceae over several ontogenetic stages (seedling, juvenile and adult), the content of leaf primordia of winter buds were studied and compared with the number of leaves of shoots developed from buds in equivalent positions. Two of the species, Embothrium coccineum and Lomatia hirsuta, have scaly buds in which green leaf primordia are covered by leaves devoid of lamina and with a broad base (cataphylls). For both species shoot growth included neoformation, and the juvenile ontogenetic stage was the most vigorous one in terms of shoot growth. The other two species, Lomatia ferruginea and Gevuina avellana, had naked buds and entirely preformed shoots along their whole ontogenetic gradient; in these two species shoot vigor was relatively constant throughout ontogeny. Both species with naked buds are present exclusively in the phytogeographical Valdivian district, while both species with scaly buds are distributed throughout the gradient of the Andean-Patagonian forests. A detailed description of bud structure, preformation and neoformation through ontogeny may contribute in our understanding of the growth, functioning and distribution of Protaceae species. Molecular phylogenetics of Gondwanan stoneflies (Antarctoperlaria; Notonemouridae): vicariance or dispersal? MCCULLOCH G.*; WALLIS G. and WATERS J. University of Otago *mccgr610@student.otago.ac.nz The widespread but disjunct distributions of many Southern Hemisphere taxa have fascinated biogeographers for more than two centuries, with these distributions either explained by vicariance associated with Gondwanan fragmentation or trans-oceanic dispersal. The origin of New Zealand’s biota in particular has been extensively debated, with suggestions that New Zealand’s biota may have been wiped-out during the Oligocene marine transgression 25 million years ago. Stoneflies (Plecoptera) are a widespread order of freshwater insects whose poor dispersal ability and intolerance for salt water make them ideal candidates for Gondwanan relicts - taxa whose distribution can be explained by vicariant isolation driven by the breakup of Gondwana. Here we use DNA sequences (mitochondrial COI, nuclear 18S and H3) to reconstruct the phylogenetic relationships among Southern Hemisphere stoneflies (5 familes; 86 genera), and use a relaxed molecular clock to estimate the chronology of diversification. We find dispersal played an important role in the contemporary distributions of the Southern Hemisphere stoneflies, with the distribution patterns and timing of splits inconsistent with the vicariance scenario. We find no evidence for the continuous existence of stoneflies in New Zealand since its separation from Gondwana, with all New Zealand’s stoneflies estimated to have arrived by dispersal within the last 20 million years. Phylogeography of Weinmannia trichosperma in present range distribution MONTENEGRO P.N.* Universidad de Chile *paz.montenegro@gmail.com The climatic and geomorphological changes associated to the glacial-interglacial cycles in late Pleistocene in South America are proposed as the main shaper in temperate forest distribution. In Chile, it has been proposed that as a result of the LGM the forest taxa had a contraction on their distribution range in ice-age refugia located in the Coastal Range, and expanded to their present distribution as the ice receded, supported by biogeographic patterns, geomorphologic evidence and fossil record. Recently, it has been refuted by genetic evidence from cold-resistant taxa. From this evidence, it has been postulated that the forest taxa survived in small and multiple refugia located in both slopes of the Andes under the influence of the ice. To test this, W. trichosperma is proposed for a phylogeographic study using patterns of genetic diversity of sequences of cpDNA. This tree is a pioneer tree of the temperate north Patagonian rainforest and it has been frequently used in palaeoclimatic reconstruction. The main aim is constructing a model of expansion of distributional range under a refugia scenario. cpDNA was extracted, amplified, purified and sequenced from individuals throughout the present distribution. Genetic indexes and statistics were calculated to test whether the pattern of molecular distribution in space is due neutral molecular evolution through time. Preliminary results shows 13 haplotypes distributed uniformly throughout present distribution. Acknowledgments: FONDECYT 1060041–1090339, ICM P05-002, PFB -23 CONICYT, AGA. Biogeographic regions of Chilean Asteraceae: traditional and new approaches MOREIRA-MUñOZ A.* (1); MORALES V. (1) and MUñOZ-SCHICK M. (2) (1) 1Instituto de Geografía, Pontificia Universidad Católica de Chile (2) 2Museo Nacional de Historia Natural, Casilla 787, Santiago, Chile *asmoreir@uc.cl Biogeographic regionalization of Chilean Asteraceae has been approached by means of the software NDM/VNDM that applies an optimality algorithm created for identifying areas of endemism. The data used for the analysis come from the collections of the National Herbarium at the Museo Nacional de Historia Natural in Santiago (SGO), comprising more than 25,000 records of the 120 Chilean native genera of Asteraceae. The program obtained 16 areas of endemism in continental Chile. These sets were further integrated as 6 consensus areas that are interpreted as the floristic regions of the Chilean Asteraceae. Being aware of the limitations of the program, in relation of the effect of the scale and the origin of the grid, novel methods to improve the distributional information of the taxa were explored. This comprises the application of niche modeling, by means of the program MAXENT, applied to the species of Mutisia. These results will serve for improving the field work as well as an input to the discussion about the origins and evolution of the Asteraceae in Chile and South America. Acknowledgements Claudia Szumik, Tania Escalante, and Patricio Pliscoff helped with the programs. Project sponsored by Fondecyt Iniciación (2008) 11085016. Tracing the origins of Iguanid lizards and Boine snakes of the Pacific NOONAN B. (1) and SITES J.* (2) (1) University of Mississippi (2) Brigham Young University *Jack_Sites@byu.edu In 1947, when Thor Heyerdahl’s Kon-Tiki hit ground in the Tuamotu Archipelago, 102 days and ~4,000 km from its point of origin in South America, he inadvertently provided support for one of the most remarkable hypotheses of vertebrate dispersal. Iguanid lizards and boine snakes are ancient, Gondwanan lineages whose distribution has been demonstrated to have been influenced by continental drift. Their enigmatic presence on the islands of the Pacific however, has drawn fantastical conclusions of 8,000+ km rafting from the Americas. We re-examine the hypothesis of dispersal in light of new multi-locus molecular data and divergence-time estimates. Our results suggest an early Paleogene (50 - 60 MYA) divergence of these groups and the plausibility of an Asiatic or Australian (over land) source. As the subfossil record indicates iguanas (but not snakes) were a primary food source of island inhabitants, the absence of these species from islands with a longer history of human presence is unsurprising. Together these findings are taken as evidence of the influence humans have had on these taxa and are put forth as an example of anthropogenic disruption of the signal of biogeographic history. We suggest this history is one of terrestrial connections permitting the colonization of the islands of the Pacific. Importance of long distance dispersal in colonization processes of sub-Antarctic islands BORN C.* (7); MC GEOCH M.A. (8); SHAW J. (2); BERGSTROM D. (9); LEBOUVIER M. (6); CHOWN S.L. (2); PEAT H. (3); CONVEY P. (4); UPSON R. (5); PADIN A. (1); GROSFELD J. (1) and JANSEN VAN VUUREN B. (10) (1) Instituto Nacional de Investigaciones en Biodiversidad y Medioambiente, Universidad Nacional del Comahue y CONICET, Argentina (2) Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, South Africa (3) British Antarctic Survey, NERC ,UK (4) British Antarctic Survey, NERC, UK (5) Falklands Conservation, UK (6) Université Rennes 1, CNRS, UMR 6553, France (7) Evolutionary Genomics Group, Department of Botany and Zoology, Stellenbosch University, South Africa (8) Cape Research Centre, South African National Parks, South Africa (9) Australian Antarctic Division, Australia (10) Evolutionary Genomics Group and Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, South Africa *celineborn@hotmail.com Vicariance and long-distance dispersal (LDD) are commonly invoked to explain the disjunct distribution of related taxa among Gondwanian landmasses. The relative importance of each process remains problematic to disentangle, mostly because LDD remains challenging to quantify. In this study, we focus on the sub-Antarctic region, including magellanic South America, Malvinas/Falkland Islands and islands for which historical biogeography strictly relies on LDD. Our aim is to evaluate the importance of dispersal throughout the Southern Ocean. Both chloroplast and nuclear genetic markers were sequenced to compare phylogeographic patterns of two perennial plant species, Acaena magellanica and Azorella selago. For both species phylogeographic patterns are very similar notwithstanding different modes of dispersal. Phylogeographic patterns also reveal a strong relatedness between Tierra del Fuego and most sub-Antarctic islands lineages, with only little divergence among islands. In contrast, our results show that Malvinas/Falkland Islands and Macquarie Island are very divergent from other lineages. These results show that the presence of both species on Malvinas/ Falkland Islands may predate the Gondwana breakup. The propagules responsible for the early colonization of sub-Antarctic islands may originate from Tierra del Fuego. Finally, the absence of divergence among islands shows the importance of gene flow between most sub-Antarctic islands, with the exception of Macquarie Island. Biogeografic distribution of the Arachis (Leguminosae) karyotype variants ROBLEDO G. (1) and SEIJO G.* (2) (1) Instituto de Botánica del Nordeste (UNNE-CONICET) (2) Arachis is a South American genus of geocarpic and *seijo@agr.unne.edu.ar Arachis is a South American genus of geocarpic and autogamous legumes. Section Arachis includes 29 diploid and two allotetraploid taxa. Three different genomes (A, B, D) have been described for the section based on karyotype morphology and cross compatibility. Geographically, the section extends southward of the Amazonian basin until La Plata River, and from the Andes mountains toward the Atlantic Ocean. The particular reproductive system of these species, autogamy and geocarpy, drastically reduces the chances of pollen and seed dispersion, and suggests that the karyotype variability should be geographically structured. To test this hypothesis, we conducted FISH analysis using rDNAs and heterochromatin detection in 29 species. We detected seven karyotype patterns, three for the A-genome, three for the B-genome, and one for the D genome. Each of the patterns detected within a particular genome was biogeographically segregated. Overlapping distributions of species having different karyotype patterns always correspond to species with different genomes. This non-random occurrence of karyotype variability is probably reflecting the biological constrains for gene flow and seed dispersion, and suggest independent species radiation of the A and B linages. Notoriously, most of the karyotype patterns are usually associated to a particular river basin, which strongly suggest that past and present dispersion through hydrochory may have determined the geographical structure of karyotypes. Natural range of the Patagonian beeches “Raulí” and “Roble Pellín” in Argentina - Scale 1:250,000 SABATIER Y.* (1); PASTORINO M.J. (2); UMAñA F. (1) and BRAN D. (1) (1) Lab. de Teledetección y SIG, INTA - EEA Bariloche (2) UGEMFor, INTA - EEA Bariloche (investig. CONICET) *ysabatier@bariloche.inta.gov.ar Knowing in detail the natural distribution area of any forest tree species is essential for planning the management and conservation of its resources. Within the emblematic genus Nothofagus, Raulí (R) (N. nervosa) and Roble Pellín (RP) (N. obliqua) are noteworthy in the temperate forests of Argentina due to their restricted range and valuable timber. Previous studies have constructed maps at 1:500,000 scale, where these two species constituted diverse forest types. The aim of the present contribution is to map the presence of both species at 1:250,000 scale, irrespective of the ecosystems they compose. For several purposes the sole presence of the species is informative. Geo-referenced 2007 Landsat-TM images adjusted to the ortho-rectified mosaic built by the University of Maryland were interpreted on monitor. For this interpretation we used previous maps of lower scale, digital information available in national and provincial agencies and local settlers’ information. Ground control was restricted to some controversial points in accessible sites. R ranges on 83,235 ha and RP on 37,380 ha (20,423 ha overlapped), being those surfaces mostly located within the National Park (NP) Administration (64,532 ha of R and 28,777 ha of RP within Lanín NP, and 12,875 ha of R within Nahuel Huapi NP). Out of the Parks, R is present in only 5,828 ha and RP in 8,603 ha, where they build marginal forest patches with relevant conservation value due to their adaptation to harsher environments. Island biogeography approach on Pampean pollination webs SABATINO M.* (1); MACEIRA N. (2) and AIZEN M.A. (1) (1) Laboratorio Ecotono, INIBIOMA (CONICET-UNCOMA) (2) EEA Balcarce, INTA *malenasabat@crub.uncoma.edu.ar Island biogeography theory predicts that species richness increases with habitat area and declines with isolation. We expand this framework to address changes in the number of links and species in pollination webs from 12 isolated hills, ranging in area from tens to thousands of hectares, immersed in the agriculture matrix of the Argentine Pampas. We also studied whether total interaction frequency is partitioned more evenly among individual links in richer webs. Our results reveal a direct effect of area on the number of links and species present in each pollination web. However, link richness increased two-fold faster than species richness with area. These area effects were not confounded by sampling effort or correlated incidence of exotic species, despite widespread habitat disturbance. Habitat proximity, an inverse measure of isolation, had a marginally significant influence on link but not on species richness. Increased link number was associated with decreasing dominance by any particular interaction and increasing interaction evenness. Despite the strong area effect, a rich pollination web sampled from a small protected sierra suggests that simple conservation measures, such as reduced grazing and fire suppression, may effectively preserve much local interaction diversity. Key words: area effect; dominance; evenness; island biogeography; isolation; link diversity; Pampas; pollination webs; species richness. Phylogeography of Eucryphia cordifolia: Glacial history and genetic diversity in Temperate Rainforest of South America SEGOVIA R.* (1); PéREZ M.F. (2) and HINOJOSA L.F. (1) (1) Universidad de Chile, IEB (2) Pontificia Universidad Católica de Chile, CASEB *segovia@ug.uchile.cl Southern South American temperate forests have been strongly impacted by Pleistocene glacial-integlacial periods, reducing the area available to the tree species. Biogeographical and palaeoecological evidence suggest that temperate forest species survived in the lower and middle parts of Coastal area of southern Chile between 36-40º. Phylogeographic studies in cold tolerant tree species, suggest that forest may also survived in multiple local ice-free areas. Here, we tested the hypotheses of single vs multiple “refuges” by a phylogeographic study in Eucryphia cordifolia, a thermophilous tree. We sequenced the trnV-ndhC intergenic region of the cpDNA in 150 individuals from 22 localities from the total distributional range in Chile. Nine haplotypes were distinguished. The highest variation occurr within populations, whereas the lowest variation among populations. Coastal populations localized in the central range of E. cordifolia concentrate the highest cpDNA genetic diversity. These results are consistent with the hypothesis that a single coastal refuge was maintained during LGM around 40°S. The decrease in the number of haplotypes and genetic distances towards the edges of the distributional range, suggest a recolonization from these coastal refuge. In addition to the south-north contractions during ice ages, we propose that E. cordifolia also suffered north-south contractions during warmer and drier periods during the Holocene. FONDECYT1090339/1060041;IMEBP05-002;CONICYT. Biogeography of Gondwanan Grasses SIMON B.S.* Queensland Herbarium *bksimon43@gmail.com GrassWorld, an information system of world grasses that includes TDWG plant distribution information, provides a data source for examining biogeographical information of the grass family Poaceae. The grass floras of Gondwanan regions were analysed and the total number of all species, native genera and species, and endemic genera and species are presented graphically. Southern South America, India and Australia have the largest grass floras, with Australia having most endemic genera and species. Panicoid species dominate all regions except SSA and New Zealand, where pooids are more common. Chloridoids and aristidoids are best represented in Southern Africa and Australia. Bambusoids feature well in India and are poorly represented in Southern Africa and Australia, although they are more prolific in adjacent Madagascar, New Guinea and New Caledonia. Danthoniods feature in all southern continents and micrairoids are almost entirely restricted to Australia. Present day distributions of grasses are discussed in terms of the evolution and distribution of the Poaceae. Each Gondwanan region is summarised in terms of the unique features of their native grass floras. Some regions have large genera that are either endemic or have many endemic species (Triodia, Eriachne, Micraria in Australia; Pentaschistis in Southern Africa; Poecilostachys in Madagascar; Chionochloa in New Zealand; Dimeria and Ischaemum in India; Festuca, Nassella, Pappostipa and Poa in southern South America). Distributional range of two endemic species from Southern South America Chiasognathus granti and C. jousselini VERGARA O.*; HERNANDEZ C. and JEREZ V. Universidad de Concepcion Chile *olvergar@udec.cl The fragmentation of Valdivian temperate forest, the main habitat of Chiasognathus granti and C. jousselini, altered the refuge places, foraging and breeding of these species. Endemic to the southern of South America these emblematic stag beetles could be considered important component to the conservation programs. Our aim was determine the distribution range of these species and its relationships with vegetation and climate variables. We build a database based on locality records, bibliographic review (1950-2008 years), museum's collections and field collection. To estimate the potential distribution in Chile-Argentina we used a Maximum Entropy model using climate variables derived from Intergovernamental Panel on Climate Change. This model showed that the distribution of C. granti was modeled by rainfall and the distribution of C. jousselini by the ecoregions that suggests that the last species is more susceptible to habitat fragmentation. Potential distribution of C. granti is overlapping with Pleistocenic Refuges (Lake and Aysen Regions and Chiloe island in Chile). Finally both species respond differently to the ecosystem degradation so a differential conservation plan and/or management is needed for both. Keywords: Gondwana, Nothofagus, Biogeography. Diversification of a Gondwanan mistletoe family: Loranthaceae VIDAL-RUSSELL R.* (1) and NICKRENT D.L. (2) (1) Universidad Nacional del Comahue (2) Plant Biology, Southern Illinois Univ. Carbondale *vidalrussell@gmail.com Loranthaceae is the largest mistletoe family with 73 genera and ca. 900 species. It is distributed mainly in tropical areas worldwide, but members are also found in temperate and Mediterranean biomes in South America, Australia, New Zealand, Asia, Africa and Europe. The objective of this study was to reconstruct the biogeographic history for Loranthaceae using a molecular phylogeny based on five genes. The phylogeny was then reconciled with present day distributions, fossil data, tectonic data and biological factors. Penalized likelihood was used to estimate divergence times using several fossils as time constraints. The distribution of Loranthaceae was divided into seven geographical areas that correspond mainly to the continents and these were optimized on the phylogeny. Ancestral area reconstruction suggests an origin of the family in Gondwana in the late Cretaceous with a probable vicariance event that separated taxa between Australia and South America in the Eocene, a date in agreement with geologic data. Further dispersal events from Australia into New Zealand and Asia and from Asia into Africa are necessary to explain the current distribution of taxa. During the Eocene, Australia achieved complete isolation from Antarctica and the Drake Passage between Antarctica and South America opened, thus changing world climate. According to our molecular dating, these events coincide with the evolution of aerial parasitism and diversification of mistletoes in Loranthaceae. Range-wide phylogeographies of three widespread Australian cool temperate rainforest plants WORTH J.* University of Tasmania *Tmesipteris@gmail.com How temperate plants and animals survived hostile climates during past glacial periods is critical to understanding modern ecological communities. Species may have survived in macro-refugia, and migrated large distances to reach their current range since climates recovered 10-12,000 years ago, or may have survived in many micro-refugia. The cool temperate rainforest of southeastern Australia provides opportunities to better understand how these processes have shaped the current biota. This talk will describe the results of my PhD thesis that investigated the range-wide chloroplast DNA phylogeographies of three Australian cool temperate rainforest plants of Nothofagus cunninghamii (Nothofagaceae), Tasmannia lanceolata (Winteraceae) and Atherosperma moschatum (Atherospermataceae). Deep divergence and strong phylogeographic patterns were observed in N. cunninghamii and T. lanceolata, the result of probable long-term survival in multiple regions, indicating the resilience of these species in apparently hostile last glacial climates. Differing dispersal traits have not affected the limited mobility of these species in response to past climatic changes. However, the very low diversity across most of the range of A. moschatum suggests a divergent history of this species. Paleobiology Leaves and insects from an early Miocene maar diatomite at Foulden Hills, Otago, New Zealand BANNISTER J. (1); LEE D.* (1); CONRAN J. (2) and KAULFUSS U. (1) (1) University of Otago (2) University of Adelaide *jennifer.bannister@xtra.co.nz Plant macrofossils collected from this varved diatomite deposit reveal evidence of a highly diverse forest surrounding a small maar lake. The dominant family is Lauraceae which comprise 40% of the leaves. Macrofossils (leaves, flowers, fruits and seeds) and palynology have shown at least 26 families of non flowering and flowering plants in the forest. One of the fern spore types has been found on fertile fronds of Davalliaceae and two flowers have in situ pollen. Only three of the flowering plant families overlap. Seven different monocotyledonous leaves are present at the site although only one pollen type has been recognized so far. Associated with the leaves are a few epiphyllous fungi and two types of scale insect. Acrodomatia, both hair tuft and pocket domatia, have been found on some leaves and many leaves show insect damage. Insect pollinated flowers have also been found. Recently about 40 insect fossils representing several insect families have been discovered in the diatomite. They are preserved as chitinous compressions and indicate a diverse arthropod fauna. The flora indicates that the maar lake was surrounded by a subtropical, seasonally dry, forest of evergreen trees, shrubs, lianes and ferns with a diverse arthropod fauna. Long-term vegetation and environmental changes at southern Patagonian steppe (Argentina) during the last 12,900 cal yrs DE PORRAS M.E.* (1); MANCINI M.V. (2) and PRIETO A.R. (1) (1) Lab. Paleoecología y Palinología, UNMdP - CONICET (2) Lab. Paleoecología y Palinología, UNMdP *medeporras@gmail.com Southern Patagonia environmental and palaeoclimatic dynamics since the Late Glacial have been based on the analysis of records located in the grass-steppe or in the forest-steppe ecotone whereas those from the semi-arid areas which occupy most of the Patagonian Steppe have been hardly investigated. The present study therefore aims to present the long-term vegetation and environmental changes of the Santa Cruz Central Plateau (46-49°S; 67-71°W) since 12,900 cal yrs BP through the pollen analysis of caves. Furthermore, pollen taphonomic processes were analyzed to determine whether the pollen record changes were related to anthopogenic, biotic or abiotic forcings. The major vegetation and environmental changes were recorded around 11,800 and 4038 cal yrs BP and at the beginning of the 20th century but related to different forcings. At 11,800 cal yr BP a dwarf-scrub steppe related to colder conditions but the same precipitation values than present was replaced by a shrub-grass steppe suggesting a gradual increase in temperature that continued until 5000 cal yrs BP when the vegetation and environmental conditions were similar to the present. At 4038 cal yrs BP the shrub communities changed because of the fall of the volcanic ash from the Hudson volcano H2 eruption just affecting some species. At the beginning of the 20th century, the introduction of sheep did not produce changes on the vegetation because of grazing but as a consequence of the use of caves for sheltering flocks. Climate change and the Southern Hemisphere Westerlies between 14000-6000 BP: zonal symmetry or zonal asymmetry? FLETCHER M.* (1) and MORENO P. (2) (1) Instituto de Ecología y Biodiversidad (2) Facultad de Ciencias Universidad de Chile y IEB *michael.fletcher@u.uchile.cl The southern hemisphere westerly winds (SHW) are an important component of the global climate system and are one of the few truly hemisphere-wide connections in the Southern Hemisphere. The latitudinal position occupied by the SHW has varied over short and long time-scales with apparent zonal symmetry and zonal asymmetry. Zonal symmetry in SHW behaviour has resulted in synchronous hemisphere-wide climatic anomalies over the historic period and is believed to have increased degassing of CO2 from the Southern Ocean during the Last Glacial Transition. In contrast, zonally asymmetric SHW behaviour is reported from the mid-latitudes during the early Holocene: increased SHW flow over Australia and decreased SHW flow over southern South America. Analysis of how decade-scale zonal SHW movements associated with the Southern Annular Mode (SAM) impact upon climate provides valuable insights in to the relationship between the SHW and Southern Hemisphere climate. A hemisphere-wide synthesis and evaluation of vegetation, fire, hydrologic and sea-surface temperature proxies relevant to the SHW reveals that, rather than zonal asymmetry during the early Holocene, SHW changes were zonally symmetric between 14000-6000 BP. It is argued that zonally symmetric SHW changes over multi-millennial timescales result in zonally symmetric and zonally asymmetric climate changes that are governed by geographic heterogeneities in a manner reminiscent of SAM. Pollen-vegetation relationship and recent human environmental interactions in the north-eastern Patagonian Andes FONTANA S.* and GIESECKE T. University of Göttingen, Germany *sonia.fontana@biologie.uni-goettingen.de The northeast Patagonian Lake District, situated within the Lanín National Park (38.5°S, 40.5°S), is characterised by diverse vegetation gradients: (i) west to east the vegetation changes from Nothofagus rain forests to woodlands of Austrocedrus chilensis, and steppe grasslands; (ii) north to south, from Araucaria-Nothofagus mixed forest to mixed forest of Nothofagus species and; (iii) with altitude, from lowland forests to tree-lines dominated by Nothofagus pumilio. Short gravity cores recovered from small lakes (0.5-2.5 ha surface) are used to investigate how the changing vegetation composition of the region is mirrored in the pollen proportions of the surface samples and to study the impact of the recent human land use on the vegetation. Surface samples containing pollen of Araucaria araucana and/or Austrocedrus chilensis are restricted to locations where the species occurred and can thus be used as good indicators of these vegetation types. Altitudinal differences are less evident, but can be detected in a PCA plot. Short cores from 6 lakes showed similar pattern in their pollen spectra over the last few hundred years. The initial appearance of Rumex and Plantago pollen in small abundances may represent the establishment of summer pastures by Mapuche people. The later rise of these pollen types coincides with the appearance or increase of Pinus pollen, marking the arrival of European settlers and the establishment of Pinus plantation. First Argentinean fossil record of palm fruits (Salamanca Fm., Paleocene) from Chubut, Patagonia. FUTEY M.* (1); GANDOLFO M. (1); CLADERA G. (2); CúNEO R. (2) and ZAMALOA M. (3) (1) Cornell University (2) Museo Paleontológico Egidio Feruglio (3) Universidad de Buenos Aires *mkf42@cornell.edu We describe fossil palm fruits that belong to the monophyletic subfamily Arecoideae within the family Arecaceae. Fossils were collected in outcrops of the Salamanca Fm. (Danian, Paleocene, 63.3-61.9 Ma) at Ea. Las Violetas locality. The fossils are preserved as three-dimensional petrifications; longitudinal, tangential and cross-sections and CT scans were examined. The fruits are ovoid and longitudinally furrowed, with three well defined-grooves and a single germination pore that it is opposite to the pedicel. Internally, there is not a clear distinction between the exocarp and the mesocarp; the endocarp is thin and not sculptured. The fruits are single-seeded; the seeds are deltoid with an acute apex and are basally attached to the fruit, the endosperm is ruminate. Diagnostic characters preserved are the possible tannin cells near the endocarp, raphides and a system of longitudinal and radial fibrous bundles with associated brachysclereids. They present a suite of characters that correspond to members of the subfamily Arecoideae and have a possible affinity with the tribes Cocoseae and Areceae. Although the presence of fossils stems was previously known from Patagonia, this report constitutes the first record for fruit for Patagonia and for Argentina. The palaeoenvironmental history of the Paroo/Warrego Region, Australia: a multi-proxy, multi-site approach GAYLER L.* University of Newcastle *palaeolucek@yahoo.com.au The records of environmental change in Australia’s arid zone can be greatly enriched by employing a multi-proxy approach and landscape-scale analysis. This research uses these tools to construct a palaeoenvironmental history of the semi-arid wetland system of the Paroo/Warrego Region. In summary, high lake water levels prevailed prior to the Last Glacial (LG). The extreme aridity at the onset of LG caused long term drying of the lakes and mobilisation of the red sand dunes. In latter stages of the glacial phase the aridity gave way to periodic fluctuations between flood and drought events that probably lasted until 16 000 - 14 000 BP. The new climatic regime resulted in formation of gypsum lunettes and later, following reduction in gypsum supply, clay lunettes. The orientation of red sand dunes and lunettes indicates a more northerly extent of the westerlies than in modern times. Around the late Pleistocene-early Holocene boundary the climate became more stable and wetter, but still somewhat drier than during the pre-LG lacustrine phase. As a result, the region’s lakes reverted to a permanent and semi-permanent status. A strong aridity signal, comparable to the semi-regular droughts of the Last Glacial, was recorded in the Paroo/Warrego lakes during the late 1890s-1940s period of below average rainfall. It was followed by 50 years of wetter conditions with two extremely wet phases in the 1950s and the 1970s. Finally, the most recent records suggest a new drying trend. Late-Quaternary environmental changes in the Andes of northern Patagonia revealed by diatom analysis of lake sediments GUERRERO J.M.* (1); FONTANA S.L. (2); SALA S.E. (3) and GIESECKE T. (2) (1) Universidad Nacional de La Plata, Facultad de Ciencias Naturales (2) Univ. Göttingen, Dep. Palynology &Climate Dynamics (3) Univ. La Plata, Facultad de Ciencias Naturales *guerrero@fcnym.unlp.edu.ar This study is part of a multi-proxy analysis of late Glacial and Holocene environmental changes recorded in sediments from small lakes crossing the forest-steppe boundary in northern Patagonia (Argentina). Here we present data from the lake Torta (39°06’S, 71°21’W). The lake is situated on the valley floor at an altitude of 1090 m asl in a mixed forest of Nothofagus antarctica, N. obliqua and Araucaria araucana . A 10 m long core was retrieved from the lake with a depth of 3.7 m and a surface area of 1 ha. The autogenous lake sedimentation is intercalated by frequent tephra layers and redeposited material indicating flooding events. Diatom analysis shows that the lower section of the sediment sequence is frequently dominated by planktonic taxa, mainly Aulacoseira granulata, Discostella glomerata and D. stelligera, indicating relatively greater water depth, a turbulent water column and low to moderate nutrient concentrations. In the upper half of the core small fragilarioid taxa are the major constituents of the diatom communities. These benthic to tychoplanktonic diatoms are generally associated with more oligotrophic, alkaline environments, and are indicative of a lower water depth. The planktonic diatom Asterionella formosa appeared in the uppermost part of the sequence. This species is generally linked to increased lake nutrients and might be related to recent human activity in the lake catchment due to animal farming. Vegetation changes over the last 2 kyr triggered by variations in climate and disturbance regimes in Central Patagonia HENRíQUEZ GONZáLEZ W.I.* (1); VILLA-MARTINEZ R. (2) and MORENO MONCADA P. (1) (1) IEB & Dept. Ciencias Ecológicas, U de Chile (2) Centro de Estudios del Cuaternario *willybgo@gmail.com The arrival of Europeans to Central Patagonia (CP) had a profound impact in terrestrial ecosystems through the introduction of large scale disturbance regimes and exotic species. Fire was a key catalyst of this biological transformation, and its effects are expected to amplify the impacts of warming and precipitation decline on terrestrial ecosystems. Here we present high-resolution pollen and charcoal records from Lago Edita (47°S, 72°W), a small closed-basin lake located in the chilean sector of CP, to examine the relationship between vegetation, fire, and climate change over the last 2 kyr. The record shows the continuous dominance of Nothofagus, punctuated by an increase in Poaceae between 1.2-0.7 kyr BP; this was followed by a decline in Poaceae, Nothofagus, and increases in Misodendron, Cyperaceae, and Pediastrum that persists until today. Increases in Rumex and fire occurrence and a decline in Nothofagus mark the onset of European disturbance in the mid-1800s. Our results indicate that vegetation changes brought by the onset of warmer/drier conditions at 0.7 kyr BP were amplified by European disturbance, thus accounting for its modern patchiness in the Andean region of CP. Mid-cenozoic vegetation reconstruction based on palynological data from southeastern Santa Cruz province, Argentina HEREDIA M.E.* (1); PAEZ M.M. (2); GUERSTEIN G.R. (3) and PARRAS A. (4) (1) Universidad Nacional del Sur (2) Universidad nacional de Mar del Plata (3) INGEOSUR - Dpto. Geología - UNS (4) INCITAP - UNLPam *meheredia@criba.edu.ar The present work is part of a multidisciplinary project including sedimentological data, facies analysis, marine invertebrates and palynology. The aim of this study is to analyze the palynological assemblages recovered from four sections between 49ºS and 50º 30’S. In two of them crops out the Centinela Fm. at Estancia 25 de Mayo (50º30’S, 72º15’W; dated as 22.5 Ma) and La Escondida (51º24’S, 72º09’W) sections, southwestern Santa Cruz. Gran Bajo (49º31’S, 68º14’W; between 25.9 and 25.3 Ma) and Meseta Chica (49º31’S, 68º15’W) sections allow to characterize San Julián Fm. on the Atlantic coast. Here we show the results from both Gran Bajo and Meseta Chica sections. A minimum of 300 palynomorphs were counted in order to achieve, frequency diagrams and cluster analysis. The information from Gran Bajo section indicates that a large humid temperate forest developed towards the end of the Late Oligocene represented by elements belonging to Nothofagaceae and Podocarpaceae, together with an incipient herb – shrub vegetation (e.g. Proteaceae, Anacardiaceae, Caryophyllaceae y Sparganiaceae). An important pteridophytic diversity might have developed as part of the lower layer of the forest. This information is in agreement with a shallow marine environment close to the coast barely influenced by ocean waters. Upwards, in the Meseta Chica section, the elements representing the forest are still dominant though its composition changed as it is shown by the reduction of some arboreal taxa. Ecological responses to mid- and late-Holocene climate variability in the Patagonian Andes (lat. 40-43°S) IGLESIAS V. (1); WHITLOCK C. (1) and BIANCHI M.M.* (2) (1) Montana State University Bozeman Montana USA (2) INIBIOMA, CONICET, Bariloche, Argentina *virgiglesias@yahoo.com Along the eastern Andes, a prominent ecotone separates Nothofagus-Austrocedrus forest from steppe. Given that the elevational position of the ecotone is determined by effective moisture, paleoecological changes provide an opportunity to examine past climate variations. The vegetation and fire history is inferred from pollen and charcoal records obtained from 4 lakes located in the modern ecotone. On millennial time scales, late-glacial steppe was replaced by open forest in the early Holocene and then by closed forest in the middle and late Holocene. Highest fire activity was reached between 3 and 1 ka. The long-term vegetation and fire patterns are partly explained as a response to variations in insolation. In the last 5000 years, changes in precipitation and ENSO variability, inferred from independent data, matched closely with trade-offs in the abundance of Nothofagus, Austrocedrus, and Poaceae pollen and variations in charcoal abundance. Four climate scenarios (dry conditions with low variability, dry conditions with high variability, wet conditions with high variability and wet conditions with low variability) registered distinctive ecotonal responses. Our findings suggest that precipitation and ENSO variability explain much of much of the fine-scale vegetation and fire signal in the late Holocene but that these relations must be understood in the context of millennial-scale variations in climate that shape the broad patterns of vegetation and fire in the region. Temperate rainforest response to climatic, volcanic, and fire influences in NW Patagonia over the last 15,500 years JARA I.* and MORENO P. Universidad de Chile *elignaciojara@gmail.com Few studies in southern South America have examined the interplay between vegetation and climate change with disturbance agents such as fire and volcanism throughout the Holocene. Detailed studies from small, closed-basin lakes located in the vicinity of active eruptive centers offer a prime source of information to monitor the influence of climatic and non-climatic agents of vegetation change regimes. Here we present high-resolution pollen and charcoal records from Lago Pichilafquén, a site located in the Andean foothills of NW Patagonia (40ºS). Between 15.5-7.2 ka (ka=1000 cal yr BP) the record shows a pattern of vegetation change coherent with other pollen records in the region, suggesting that climate change exerted a primary control at millennial timescales. Divergence from this pattern between 7.2-2.7 ka is concurrent with the presence of several pyroclastic layers. The local fire history follows a regional, climate-driven, trend at multimillenial timescales. At shorter timescales, however, we observe a tight relationship with volcanic disturbance. Our results suggest that volcanic eruptions have impacted the vegetation and paleofire regimes of NW Patagonia at submillennial timescales over the last 15,500 years. We propose that, depending on their timing and magnitude, catastrophic disturbance regimes could reinforce or attenuate the impacts of climate change in the rainforest communities of NW Patagonia, causing local departures from the regional pattern. The anatomy of watershed unraveling following early human-set fires in New Zealand MCWETHY D.* (1); WHITLOCK C. (1); WILMSHURST J. (2); MCGLONE M. (2) and FROMONT M. (2) (1) Montana State University, Bozeman, Montana USA (2) Landcare Research, Lincoln New Zealand *dmcwethy@montana.edu Late-Holocene pollen, charcoal and biogeochemical records from South Island, New Zealand indicate the arrival of Polynesians, c. 700 cal yr ago, was associated with widespread burning, loss of native forest and the unraveling of watershed conditions. High-resolution charcoal and pollen analyses were conducted on sediment cores from lakes throughout the South Island to document the fire history of the last 1000 years and the ecological response to burning. Patterns of burning and vegetation change were then compared with diatom, chironomid and element concentration data to identify the structure of biogeochemical changes that occurred following human-set fires. Data indicate one to several high-severity fires occurred in each watershed within 1-2 centuries of Polynesian arrival. This "Initial Burning Period" was the major deforestation event in the history of each watershed, and was accompanied by a dramatic transformation in vegetation, slope stability, and lake chemistry. Repeated forest burning led to mass transport of forest soils to lake systems and flux in limnobiotic conditions and lake nutrient levels, evidenced by major shifts in diatom and chironomid community composition. Our results suggest that anthropogenic burning of native forests altered watershed biogeochemistry in ways that would have long-standing impacts on the ecology of forests and that ecosystems with no previous history of fire showed little resilience to the introduction of a new disturbance. Intensity variations of the Southern Westerlies match atmospheric CO2 changes during the Holocene MORENO P.I.* (1); FRANCOIS J.P.; MOY C.M. (2) and VILLA-MARTINEZ R. (3) (1) IEB & Dept. Cs Ecológicas, U de Chile, Chile (2) Stanford University, USA (3) Centro de Estudios del Cuaternario, Chile *pimoreno@uchile.cl A suite of mechanisms has been proposed to account for natural variations in atmospheric CO2 during the present the Holocene, all of which have achieved limited success in reproducing the timing, direction, and magnitude of change. Recent modeling studies proposed that changes in the latitudinal position and strength of the Southern Hemisphere Westerly Winds (SHW) can greatly influence large-scale ocean circulation and degassing of the deep ocean via changes in wind-driven upwelling in the Southern Ocean (SO). The extent to which the hypothesized SHW-SO coupled system could account for changes in atmospheric CO2 is uncertain, because of a lack of observations on the behavior of the SHW in the past. Here we report a reconstruction of the behavior of the SHW during the last 14 kyr based on terrestrial ecosystem proxies from western Patagonia. The reconstructed variations in the intensity of zonal flow correspond to the timing and structure of CO2 changes during the last 14 kyr, and are consistent with the modeled magnitude of CO2 changes induced by varying strengths of the SHW, thus supporting the view that the SHW-SO system underpins CO2 change during the present interglacial. Mid-late Holocene vegetation, fire, and climate history of west-central Argentina: Laguna El Sosneado record NAVARRO D.* (1); WHITLOCK C. (2); PAEZ M.M. (3) and ZARATE M.A. (4) (1) CONICET. Lab. Paleoecología y Palinología. UNMdP (2) Paleoecology Lab. Montana State University (3) Lab. Paleoecología y Palinología. UNMdP (4) CONICET-INCITAP. UNLPam *navarro.dd@gmail.com In southern South America, widespread aridity has been postulated during the mid Holocene, followed by wetter conditions. There is little paleoenvironmental information available from west-central Argentina to support this hypothesis. New Holocene records from the upper Atuel River basin (34°47’S, 69°52’W) provide information on the environmental history of the region and offer a comparison with other records. Pollen data from Laguna El Sosneado shows shrub steppes between 6400-3300 cal yr BP, suggesting moderate but wetter than present conditions. During this interval, high-resolution charcoal records suggest that fires were frequent. Between 3200-1900 cal yr BP, an increase in Poaceae, Apiaceae and other shrubs suggests higher effective moisture. High fire activity at this time is explained by the greater abundance of fine fuels as suggest the high grass/total charcoal proportions. Sparse vegetation and dry conditions are inferred between 1900-700 cal yr BP based on an increase in Chenopodiaceae, Asteraceae, Ephedra, Schinus and Andean-Patagonia taxa. The lack of fuels resulted in extremely low fire activity. The last 700 years mark the development of modern semi-arid conditions. Wet conditions in the Andean foothills during the middle Holocene contrasts with postulated arid conditions. Our reconstructions agree with the dry-wet periods recorded in northern-Patagonia and neoglacial advances documented in the area showing a strong relationship with the westerlies dynamic. Millennial-scale changes in hydrobalance in NW Patagonia since 18 kyr revealed by Lago Lepué (Isla Grande de Chiloé, 42ºS) PESCE O.* and MORENO P. Dep. Ciencias Ecológicas U. de Chile & IEB. *opesce@gmail.com Our knowledge on variations of the Westerly winds in Southern South America since the last glaciation relies primarily on the climatic interpretation of paleovegetation records, lake level reconstructions, and a few marine offshore cores. Inferences based on palynological records have utilized the zonation of the upland vegetation along the modern climate space as indicators of past temperature and precipitation changes. Terrestrial ecosystems, however, are subject to multiple driving forces other than climate change including, among others, disturbance regimes, ecological interactions, and edaphic processes. Here we present an 18 kyr-long record from Lago Lepué, a small closed-basin lake located in Isla Grande de Chiloé (42ºS-72ºW), that shows changes in precipitation regimes (deduced from changes in the upland vegetation) and lake levels (illustrated by variations in the littoral macrophyte Isoetes, and stratigraphic indications of transgressive/regressive phases). The record shows that Isoetes and paleofires covary at millennial timescales since 18 kyr BP, including a prominent lake level drop between 10.5-7.8 kyr BP. Nothofagus, a cool-wet indicator, in contrast varies in antiphase relative to Isoetes and local paleofires, Our results provide firm evidence for changes in vegetation and lake levels, produced by millennial-scale changes in precipitation of westerly origin since the end of the LGM; the implications of which will be discussed during the presentation. Unstable conditions in lake Cari-laufquen(41º 30' 08'' S; 69º 30' 28'' W), Patagonia, during the late Pleistocene (21000-16000 cal yrBP) PINEDA D.* (1); CUSMINSKY G. (2); SCHWALB A. (3) and ARIZTEGUI D. (4) (1) CRUB/UNCo (2) CRUB/INIBIOMA/UNCo/CONICET (3) Inst. für Umweltgeologie, TU Braunschweig, Germany (4) Earth Sc Section,University of Geneva, Switzerland *gcusminsky@gmail.com Lake Cari-laufquen, located in northern Patagonia, Argentina is one of the few sites providing a long and short-term climate processes. Studies on shorelines features, demonstrate large lake-level changes during the late Pleistocene. Here we use ostracodes, from lake Cari-laufquen Grande, in order to reconstruct the palaeoecological, palaeoenvironmental conditions and stability of the environment during the late Pleistocene (21.692 ± 288 cal yr BP to 16.960 ± 239 cal yr BP). Four ostracodes species were found from surface sediments sampled along a transect from 1999 lake shore uphill for 150 to 200m. The species identified are Limnocythere rionegroensis Cusminsky and Whatley, Eucypris virgata Cusminsky and Whatley, Eucypris fontana (Graf) and Limnocythere patagonica Cusminsky and Whatley. Two associations were distinguished the first composed of L. rionegroensis and E. virgata, between sample M1.20 to M1.28, characteristic of freshwater environment, and the second, between sample M1.29 to M1.40, by L. rionegroensis and E. fontana characteristic of saline environment. These variations reflect a change from a freshwater to saline lake system during the late Pleistocene documented a high lake level stage and a lower thereafter. This is consistent with other studies, where established that the conditions during Pleistocene were moister and cold. Later on, the environmental conditions changed to arid leading to a shrinking of the lake and turning the conditions saline. Vegetation response to different forcings during the Holocene in the Río de la Plata grasslands and southern Patagonia PRIETO A.R. (1); MANCINI M.V. (2); STUTZ S. (2); VILANOVA I. (2) and TONELLO M.* (2) (1) Lab. Paleoecología y Palinología. Universidad Nacional de Mar del Plata, Funes 3250, 7600 Mar del Pl (2) Lab. Paleoecología y Palinología. UNMDP *aprieto@mdp.edu.ar This project is being carried out to improve the understanding of the Río de la Plata grasslands (RPG) and southwestern Patagonia (SWP) paleoclimate based on new palynological records from different environments with different temporal resolution since the Last Glacial. Both areas were selected considering their vulnerability to the present climate change. The aims are to obtain a better insight into paleoclimatic interpretations, to distinguish natural (climate change, sea-level fluctuations, volcanic eruptions) from anthropic forcing implied in vegetation changes, to analyze if the same forcings were at work in both areas for different time-windows, and to identify fire frequencies related to different climatic conditions and human impact. Holocene quantitative climatic estimations from the RPG and SWP pointed out that the variability of Pann associated to changes in the atmospheric circulation was a major forcing in both areas. However, temperature change did also induce vegetation changes in the northern Santa Cruz forest and in the semi-arid steppes. In southern Patagonia fire regimes could be closely related to the Pann trends but whether these have a direct effect on vegetation or not need further analysis. During the mid-Holocene RPG coastal vegetation was strongly influenced by sea-level fluctuations and volcanic ash fall influenced the semi-arid Patagonian communities. Anthropogenic forcings has been a major cause of vegetation change since the European settlement. Proyecto Interdisciplinario Patagonia Austral (PIPA) – Goals and work in progress RAMóN MERCAU M.J. (1); ECHAZú D.M. (2); ORPELLA G.* (3); LAPRIDA C. (4) and MASSAFERRO J. (5) (1) DBBE, FCEN-UBA; ANPCyT (2) DBBE, FCEN-UBA (3) CENAC, APN-CONICET; ANPCyT (4) DCG, FCEN-UBA; CONICET (5) CENAC, APN-CONICET *noramaidana@yahoo.com.ar Diatoms, chironomids and ostracods are widely used as proxies for palaeoenvironmental reconstructions due to their sensitivity to environmental parameters such as temperature, conductivity, pH, dissolved oxygen and precipitation, among others. Quantitative reconstructions require the compilation of extensive datasets involving species abundance, distribution and ecological data to be used as training sets for transfer functions development. The aim of the interdisciplinary project PIPA (PICT/REDES 2338) is the reconstruction of the natural history of southern Patagonia, between 49 and 52ºS, in Argentina, and it is currently undertaking a compilation of diatoms, chironomids and ostracods diversity database for southern Santa Cruz province, for quantitative palaoenvironmental inferences. To date, surface sediments and water samples have been retrieved from 16 permanent and ephemeral waterbodies, representing a gradient of lentic ecosystems. Using multivariate statistical analysis, the diversity and abundance of the species found were related to physical and chemical parameters in order to explore their relationship. Our results suggest that water solute composition and dissolved oxygen concentration could be the main drivers of the biodiversity and distribution of the taxa under study. Lateglacial and Holocene chironomid-inferred temperature records from Tasmania, Australia REES A.* and CWYNAR L. University of New Brunswick *a.rees@unb.ca Tasmania, an island off the south-eastern coast of Australia, is ideally situated to study both lateglacial and Holocene paleoclimates. However, few well-dated, quantitative, paleoclimate records exist for the region and important questions regarding the timing and magnitude of climate events, such as the Antarctic Cold Reversal (ACR), remain unanswered. We present two chironomid-based reconstructions of temperature of the warmest quarter (TWARM), spanning the lateglacial and Holocene, from Eagle and Platypus Tarns, Mt. Field National Park, Tasmania. TWARM was reconstructed using the chironomid-based inference model from Rees et al. (2008), which has a jack-knifed coefficient of determination of 0.72 and a root mean squared error of prediction of 0.94°C. TWARM reached present-day values by 15 cal ka BP and remained high until 13 cal ka BP. These results are consistent with sea surface temperatures from south of Tasmania, but starkly contrast with vegetation inferences that generally indicate cool initial temperatures followed by a broad warm period between 11.6 to 6.8 cal ka BP. Interestingly, the chironomid-inferred TWARM records suggest high temperatures during the ACR; however, an ACR-like signal is evident in the loss-on-ignition profiles from both sites. A mid Holocene thermal maximum (HTM) from 7 to 4 cal ka BP corresponds with warming inferred from the development of Nothofagus cunninghamii-dominated rainforest at Mt. Field. Vegetation and fire dynamics during the Holocene in the Southwest Nothofagus foreststeppe ecotone (Argentina) SOTTILE G.D.* (1); BAMONTE F.P. (2); MANCINI M.V. (3) and BIANCHI M.M. (4) (1) Lab. Paleoecología y Palinología. UNMdP. CONICET (2) Lab. Paleoecología y Palinología. UNMdP. ANPCyT (3) Lab. Paleoecología y Palinología. UNMdP. (4) INIBIOMA-CONICET – UNCo *gonzalo_sottile@yahoo.com.ar Fire regimes strongly influence structure and functioning of ecosystems. Spatial and temporal patterns of fire activity affect plant communities including floristic and life-form composition, diversity and productivity. The aim of the present study is to reconstruct fire and vegetation dynamics of the Southwest of Santa Cruz province during the Holocene. Pollen and macroscopic charcoal analysis from two peatbogs located at Cerro Frías (50ºS, 72º42’W) and Ea. La Tercera (49ºS, 72º22’W) were carried out. The first bog is located in the forest-steppe ecotone and the second one is placed in the grass-shrub steppe ecotone, eastward of the forest limit. Charcoal records show moderate values in charcoal accumulation rates (CHAR) and CHAR Background up to 6500 cal yrs BP. Between 5000-4000 cal yr BP there is a sharp decrease in fire frequency and CHAR. By 3000-4000 cal yrs BP, the highest CHAR, peak magnitude, and CHAR Background values are recorded. This is associated with a Nothofagus decline (at 50ºS) and a vegetation turnover from a shrubby to a grass steppe (at 49ºS). Around 1000 cal yrs BP fire frequency decreases again and fire activity slightly increases up to the last 400 cal yrs BP. The periods showing low fire frequencies are related to low background values suggesting low biomass availability or fuel discontinuity on the eastern steppe communities. In forest communities at the west, this kind of fire regime seems to be linked to very high or very low precipitation values. Decadal-scale changes in vegetation and paleofires in the Andean region of NW Patagonia during the last 3000 years (41°S) VALENZUELA SAAVEDRA M.A.* and MORENO MONCADA P.I. IEB and Depto. Ciencias Ecológicas, U. de Chile *melitavalenzuela@hotmail.com Several paleoclimate records have suggested centennial-scale changes in the mean climate state and/or intensification in its variability during the last 3000 years, including multiple Neoglacial advances in the Andes Cordillera and New Zealand´s southern Alps and an accentuation of the El Niño-Southern Oscillation phenomenon in tropical environments. The extent to which these changes affected the temperate rainforests, precipitation and natural fire regimes of NW Patagonia has not been investigated in detail. Here we present high-resolution pollen and charcoal records from two small closed-basin lakes located in the Andean region of the Chilean Lake District (41°S), with the aim of understanding the coupling between vegetation, climate, and disturbance regimes at decadal-scale resolution during the last 3000 years. The data show centennial-scale alternations between N. dombeyi and the thermophylous trees Eucryphia/Caldcluvia and Aextoxicon punctatum, in conjunction with Poaceae. Our results indicate relatively warm/dry conditions between 3.2-2.2 ka, followed by cooler/wetter and absence of paleofires between 2.2- 1.3 ka, which shift to drier conditions and increased fire activity between 1.3-0.75 ka. Increased precipitation between 0.75- 0.4 ka led to a decline in paleofires, followed by abrupt vegetation changes associated with European disturbance by fire and changes in the land use. Agradecimientos: ICM P05-002, PFB-23, Fondecyt 1070991. Moisture changes during the Little Ice Age (LIA) and Medieval Climate Anomaly (MCA) in NW Patagonia VIDELA CONTRERAS J.* (1) and MORENO MONCADA P. (2) (1) IEB and Dept. Ciencias Ecológicas, U de Chile (2) IEB and Dep. Ciencias Ecológicas, U de Chile *javieravidela@gmail.com The occurrence of LIA (~0.7-0.1 kyr BP), MCA (~1.2-0.7 kyr BP), and several oscillations that preceded them remains poorly understood and replicated in the southern mid-latitudes, owing to the limited span, resolution, and sensitivity of the few available records. Here we present high-resolution paleoecological records from small, closed-basin lakes in the lowlands of NW Patagonia to determine whether there are distinguishable centennial-scale temperature/precipitation anomalies over the last 2 kyr. We found a conspicuous warm/relatively dry interval between 1.2-0.6 kyr BP. This was followed by an increase in hygrophilous trees that persisted until ~0.48 kyr BP. Forest taxa indicative of warm/relatively dry conditions reexpanded at that age until the onset of intermediate- or large-scale disturbance by fires set by Europeans sometime between ~0.4-0.3 kyr BP, depending on site location. Intersite divergences indicate strong spatial heterogeneities in vegetation and susceptibility to fire occurrence, suggesting significant spatial variations in fire occurrence. The regional and hemispheric implications of these findings will be discussed during the presentation. δ13C, C/N and pollen as Holocene environmental indicators in northeastern Buenos Aires coastal marshes, Argentina VILANOVA I.* (1); MALAMUD-ROAM F. (2); INGRAM B.L. (2) and YANG W. (2) (1) CONICET-UNMdP. Lab. Paleoecolog¨ªa-Palinolog¨ªa Arg (2) LESIG. University of California, Berkeley. USA *isabel_vilanova@hotmail.com We present carbon isotopes, C/N ratios and fossil pollen which provide a record of changing paleoenvironmental conditions from a sedimentary sequence from Rio Salado, a coastal marsh in northeastern Buenos Aires, Argentina. Surface sediments from local modern coastal environments were used to calibrate the proxy-methods so that records from the paleo-sediments could be interpreted. Vegetation changes, as revealed by variations in the δ13C and pollen data, indicate a transition from high marsh conditions to unstable low marsh/intertidal conditions occurring between 7700-5870 14C yr BP, possibly related to a mid- Holocene sea-level high stand. This interpretation is supported by shell deposits found in the sediments. Unstable estuarine marsh conditions prevailed until ca. 4300 ¨C 1500 14C yr BP, replaced by brackish to freshwater marsh conditions, as reflected in greater diversity of vegetation. Our results demonstrate that stable C isotopes, fossil pollen and C/N ratios can be combined to reconstruct paleoenvironmental sequences in coastal marshes in the south Atlantic. The records reveal that sea level reached a high stand 7700 ¨C 5870 14C yr BP. These results provide insights for evaluating vulnerabilities in these coastal environments in the face of global sea level rise. The last Glacial-interglacial transition in the Andes of central Patagonia revealed by the Lago Augusta record (47°S) VILLA-MARTíNEZ R.* (1); MORENO MONCADA P. (2) and VALENZUELA SAAVEDRA M. (2) (1) Centro de Estudios del Cuaternario (2) IEB and Dep. Ciencias Ecológicas, U de Chile *melitavalenzuela@gmail.com We report a pollen record from Lago Augusta, a small closed-basin lake located near the modern forest-steppe ecotone in central Patagonia, Chile. The record is characterized by low pollen concentration and dominance of herbs, shrubs, and aquatic plants between 19.5-15.4 kyr BP, suggesting a shallow-water lake and a treeless landscape under cold and humid climate conditions. Nothofagus increased between 15.4-11.5 kyr BP, along with Podocarpus nubigena, Poaceae, Rubiaceae and Blechnum, while other taxa (Ericaceae, Empetrum, Acaena, macrophytes) decreased in their abundances. We interpret this assemblage as indicative of a rise in lake levels driven by increased precipitation and persistence of cold conditions. Herbs, shrubs, and cold-resistance trees decreased at 11.5 kyr BP, while Nothofagus continued its rising trend until it reached maximum abundance at 9 kyr BP. Forests have persisted in the region since 9 kyr BP with little changes. Forest decline and the increase of Rumex over the last few centuries indicate European disturbance. Precipitation variations revealed by the Lago Augusta record strongly suggest changes in the position of the core region of the southern westerlies. Pollen morphology of the feathery mistletoe family Misodendraceae ZAMALOA M.D.C.* (1); FERNANDEZ C.A. (1) and PICCA P.I. (2) (1) Depto de Ecología, Genética y Evolución. UBA. (2) Depto. Biodiversidad y Biología Experimental. UBA. *mzamaloa@ege.fcen.uba.ar Misodendraceae is a small family of eudicots in the Order Santalales. Its distribution is restricted to the austral South American temperate forests. The family comprises the sole genus Misodendrum with eight species of hemiparasitic shrubs mainly parasitizing the southern beech Nothofagus. Most recent works have revised the infrageneric classification based on morphological and molecular data. Nevertheless, little is known about the palynology of the family. In this contribution a thoroughly palynological analysis of 7 species, using light microscopy and scanning electron microscopy observations, is presented. Pollen grains are consistently small, periporate and equinate, although differences in size and number of pores and spines can be established. Palynological results are contrasted with previous systematic and phylogenetic studies of the family. The value of pollen morphology in distinguishing species and subgenera is evaluated. Known pollen fossil records are included. Geology and Archaeology New geological evidence for paleovegetation changes during the Miocene in Central Chile GUTIéRREZ DUARTE N.M.* (1); PEDROZA RODRIGUEZ V. (2) and HINOJOSA OPAZO L.F. (1) (1) Universidad de Chile-IEB (2) Universidad Pedagógica y Tecnológica de Colombia *gutierrezn@ug.uchile.cl Modern biogeographical pattern in the forest region from southern South America are considerate a legacy of both geological and climatic changes occurred during the Cenozoic. Highlighting the physical separation of South America from Antarctica, the Andes uplift and the Mid-Miocene Climatic Optimum. The Navidad Formation from central Chile (34ºS) provides a unique opportunity to explore the effect of those geological and climatic changes on the Chilean pre-Pleistocene biota. The Navidad Formation corresponds mainly to a shallow marine succession of siltstones, mudstones, sandstones and conglomerates. These deposits contain fossils of mollusks, foraminifera, ostracodes, corals, shark teeth and fossil leaves that were deposited in a small marginal basin in central Chile. Age and depositional environment of the Navidad Formation has been controversial and it has been dated as late Oligocene to early Miocene based on macrofossils, late middle Miocene to late Miocene or Pliocene based on ostracods and late Miocene-Pliocene based on foraminifera. The fossil floras from Navidad Formation suggest a transition between two different paleofloras: Mixed and Subtropical Neogene floras. New radio isotopic age and geological evidence, confirm that they are stratigraphically separated, with a lower to mid-upper Miocene age, contrary to previous stratigraphic correlations which suggested a same age, late Miocene-early Pliocene. Acknowledgements: FONDECYT 1090339/1060041, IMEB P05-002. Environmental and cultural changes in the forest-steppe transition, Cisnes river basin, Central Patagonia, Chile (44ºS) MALDONADO A.* (1); MéNDEZ C. (2); REYES O. (3); ABARZúA A. (4); CARDENAS M. (5); FRANçOIS J.P. (6) and MARTEL A. (7) (1) CEAZA-Universidad de La Serena (2) Dpto. Antropología, FACSO, Universidad de Chile (3) Centro de Estudios del Hombre Austral (4) Inst. Geociencias, Universidad Austral de Chile (5) Dpt Earth & Environmental Sc, Open University, UK (6) Seminar für Geographie und ihre Didaktik, Universität zu Köln, Deutschland (7) Centro de Estudios Avanzado en Zonas Áridas, Universidad de La Serena. Instituto de Geociencias, Universidad Austral de Chile *amaldona@userena.cl Cisnes river headwaters are located in the Patagonian steppe associated to a moraine complex of at least ~19.000 cal yr BP (yrBP) and close to the current location of the forest-steppe transition. We studied fossil pollen and charcoal, to assess the evolution of vegetation dynamics and their possible effect on human occupations during the Holocene. Palynological results show the development of herbaceous and shrubs vegetation between ~19.000-14.700 yrBP, associated with glacial conditions. Between ~14.700-11.000 yrBP, we observe a gradual expansion of arboreal taxa, suggesting forest colonization near the study area. Between ~8000-4000 yrBP we recorded the most significant forest development, probably due to a combination of increased rainfall and temperatures. The late Holocene shows decrease in forest indicators between ~3.000-1.500 yrBP and one important increase between ~1300-500 yrBP. The onset of the charcoal record coincides with the first human presence in the region. It shows a major development during the early Holocene and from ~5000 yrBP onwards, with maximum at 2800 yrBP. The local archaeological record shows steppe occupation from ~11.500 yrBP onwards and forest occupations only since ~2.800 yrBP. The period of major decrease of arboreal taxa and charcoal maximum coincides with the human occupation of the forest, suggesting an exploration process by steppe’s hunter-gatherers during a period of forest contraction. Acknowledgments: FONDECYT#1090027, 1050139. Alluvial fans and Late Quaternary paleoclimate – Southern Hemisphere case studies and their global context MAY J.* (1); NANSON G. (2); LARSEN J. (2); COHEN T. (3) and PREUSSER F. (4) (1) School of Earth & Environmental Sciences, University of Wollongong (2) School of Earth & Environmental Sciences, UOW (3) Dept. of Environment and Geography, Macquarie Uni (4) Institute of Geol. Sciences, University of Bern *hmay@uow.edu.au Climate is a primary control on Late Quaternary alluvial fan evolution. Past hydrological/climatic changes should thus be recorded in alluvial fan stratigraphy. We present data from three alluvial fans situated at the transition between tropical and extra-tropical (e.g. westerlies) elements of the atmospheric circulation to reconstruct Late Quaternary climatic and environmental changes. Fan stratigraphy along the eastern Andean piedmont was investigated at Cabezas (E Bolivia, ~19°S) and Riacho Seco (NW Argentina, ~24°S) was investigated based on a range of chronological, sedimentary and paleopedological methods. Both sites document synchronous shifts between fan activity (~LGM, Mid-Holocene), and periods of stability (post-LGM to ~9 ka BP, < ~4 ka BP), reflecting variations in extent and intensity of a common tropical moisture source. They differ considerably in their pre-LGM evolution. Current work is carried out at the Mt. Chambers alluvial fan at the arid eastern margin of the Flinders Ranges (S Australia, 31°S). Here, preliminary data point to a marked increase in flow regime immediately post-LGM synchronous with upstream valley-fill incision, and high lake levels and lake floor sedimentation downstream. In conclusion, the results will help to elucidate the relative roles of the southern westerlies vs. tropical moisture sources over the Late Quaternary, adding to our knowledge of Southern Hemisphere paleoclimate within a global atmospheric context. Paleoclimate Changes During the Last 20kyr From Oceanic Core MD 07 3088 (46°S) off Chilean Patagonia VINCENT M.* (1); COMBOURIEU NEBOUT N. (2); MULSOW S. (3); KISSEL C. and SIANI G. (4) (1) LSCE UMR 1572, Paris Sud 11, UACh (2) LSCE UMR 1572 (3) Instituto de Geociencias, UACh (4) IDES UMR 8148 *vincent.montade@lsce.ipsl.fr In southern Hemisphere, the Chilean Patagonia represents a key-area to understand the past and future climate variability. The “Pachiderme” cruise (MD 159), within the framework of IMAGES program (International MArine Global changES), gave the opportunity to collect a set core by the French R/V Marion Dufresne off Chilean coast from 40°S to 55°S in open ocean and in Fjords. We present here the preliminary pollen record from one oceanic core of the “Pachiderme” cruise: the MD 07 3088 (46°04’S; 76°05’W) near Taitao peninsula. The chronology is based on tephra and on the foraminifera assemblages. The pollen record expresses vegetation changes and thus climate variations. It shows several phases in the vegetation development during the last deglaciation and beginning of Holocene: before 18 kyrs the vegetation was restricted to refugia and, later, the ice cap melting allows the Peri-Glacial Vegetation development. The deglaciation shows two phases with, at the beginning, the Magellanic Moorland development, and then the North Patagonia Rainforest installation. Later than 11 kyrs and during the Holocene the North Patagonian Forest becomes more diversified. The originality of this study is due to the fact that ours pollen data are compared with oxygen isotope record from the same core and allows direct ocean/continent correlations. Potential of dung-fungi ' Sporormiella ' to resolve Southern Hemisphere megafaunal extinctions: A New Zealand case study WOOD J.* (1); WILMSHURST J. (1); WORTHY T. (2) and COOPER A. (3) (1) Landcare Research, New Zealand (2) University of New South Wales, Australia (3) University of Adelaide, Australia *larusnz@hotmail.com Sporormiella spores are widely used in the Northern Hemisphere as a proxy for past herbivore biomass, and have unrealised potential for examining Southern Hemisphere megafaunal extinctions. Moreover, Sporormiella can be directly compared to proxies for vegetation change (pollen) and fire history (charcoal) at high stratigraphic resolution, allowing unprecedented views of the order of post-settlement ecological impacts. To assess the robustness of the proxy we examined sedimentary Sporormiella in New Zealand; a land where the timing of large herbivore extinctions and introductions are well-constrained. Wetland cores exhibited significant Holocene fluctuations in, and coincidental peaks in, spore abundance; with major declines preceding the well-established extinction period (based on many dated archaeological bone middens) by several hundred years. Our results suggest Sporormiella spores in wetlands do not accurately reflect regional herbivore populations, due to complication by environmental factors. We note correlation with local moisture proxies, supporting preferential use of drier parts of wetlands by herbivores. However, Sporormiella spores in soil cores and cave sediments appear to provide a more robust proxy for herbivore biomass. Spores in a forest soil core from mountainous Fiordland accurately track historic population changes of deer, and abundant spores until the 16th – 17th Centuries AD may reflect late survival of large avian herbivores in this western refugia. Genetics Phylogeography of evergreen Nothofagus from Patagonia (Subgenus Nothofagus ) ACOSTA M.C.* and PREMOLI A.C. CRUB-INIBIOMA, Univ. Nac. del Comahue-CONICET *mcriscos@hotmail.com Geological forces have shaped the geography of the austral continents as well as the distribution of plant populations and their genetic patterns. Patagonia has suffered the impact of ancient events such as plate tectonics, sea-level changes, and even more recent Pleistocene glaciations. The aim of this study is to analyze the levels and distribution of chloroplast DNA variation in populations of evergreen Nothofagus in relation to the historical processes that occurred in Patagonia. We sampled 15 populations of N. betuloides, 44 of N. dombeyi, and eight of N. nitida along their current ranges of distribution. Non-coding regions of chloroplast DNA from 120 individuals were amplified by polymerase chain reaction (PCR) using psbB-psbH, trnL-trnF and trnH-psbA universal primer pairs. Relationships among haplotypes were analyzed by means of phylogenetic analyses of maximum parsimony, Bayesian inference, and haplotype median-joining network. We found 19 haplotypes distributed in three major clades separated latitudinally. Greatest haplotype diversity was found in Coastal Cordillera and Chiloé Island. Our results propose that populations of evergreen Nothofagus suffered significant latitudinal disjunctions due to geographic barriers as paleobasins. We hypothesize that Coastal Cordillera was a potential corridor and refuge including Chiloé Island which has probably been in close contact to continental southern areas in the past. Thanks to PICT 25833, PME 71, PIP 11420080100326. Population genetics of the Peruvian-Chilean genus Haageocereus (Trichocereeae, Cactaceae) ARAKAKI MAKISHI M.* (1); SOLTIS D.E. (2); SOLTIS P.S. (3) and SPERANZA P. (4) (1) Brown University, USA (2) University of Florida, USA (3) Florida Museum of Natural History, USA (4) Universidad de La Republica, Uruguay *monica_arakaki@brown.edu Many Cactaceae found in the Central Andes belong to tribe Trichocereeae. Phylogenetic relationships within the tribe have been historically controversial; therefore, a molecular study using chloroplast and nuclear markers was designed to elucidate phylogenetic relationships in this tribe and in the genus Haageocereus. We sequenced cpDNA (rpoB, rpl16, and 23S) and nrDNA (ITS) of 118 taxa. Seven genera were found to be outside the Trichocereeae and more closely related to Brazilian members of tribe Cereeae. Studies at the population level were carried out to examine the role of polyploidy and hybridization in the evolution of Haageocereus, Espostoa and other Trichocereeae. Chromosome counts were done for a total of 54 individuals, and they are the first chromosome numbers reported for most of these taxa. Both diploid and polyploid counts were obtained in Haageocereus, Cleistocactus, Espostoa , and Weberbauerocereus. Additionally, nineteen polymorphic dinucleotide microsatellite loci were isolated from two species of Haageocereus (H. tenuis and H. pseudomelanostele) and applied to the study of genetic diversity, population differentiation, clonal reproduction and apomixis in four species of Haageocereus. These markers will facilitate analysis of population differentiation and genetic diversity throughout Haageocereus. Our studies support the hypothesis that polyploidy and hybridization have played prominent roles in the evolution of several genera in the Trichocereeae. Fertility of Aechmea caudata and A. winkleri (Bromeliaceae) in Southern Brazil BUTTOW M.V.* (1); GOETZE M. (1); PAGGI G.M. (2); ZANELLA C.M. (1) and BERED F. (1) (1) Universidade Federal do Rio Grande do Sul - UFRGS (2) Universidade Federal do Mato Grosso do Sul UFMS *miriamvb@gmail.com Plant fertility and population arrangement are related with many questions on plant evolution and conservation biology. Pollen availability and viability, abiotic resources and flowering pattern can limit fruit and seed set. Aechmea caudata and A. winkleri are two close related bromeliad species differing in geographic distributions. While the former is widely distributed throughout Atlantic Rain Forest, the latter is endemic of a small region in the Southern Brazil. This study aims to verify the potential of reproductive output in both species. Hence, we analyzed the following components of fertility: a) flowers, fruit and seed set, flowering and fruiting pattern and the heights of plant and inflorescences; b) pollen viability; c) levels of seeds germination and d) demographic patterns. A. caudata always showed higher values in the number of flowers, plant and inflorescences height (P < 0.0001). However, A. winkleri showed a higher proportion of pollen viability: 91.0% (SE ± 3.4) than A. caudata (69.3% ± 4.19). Seed viability was high in all populations evaluated, with more than 94% germinated in seven days. Demographic data revealed that both species has a high level of clone reproduction. For each genet recorded there was an average of 20 ramets. Populations showed preference for shaded environments, rocky substrates and groups. These data, together with those obtained in studies of reproductive biology, will be useful to plan conservation strategies for these species. Testing the central-margin hypothesis into a phylogeographical framework in the Patagonian plant Calceolaria polyrhiza COSACOV A.* (1); SéRSIC A. (2); JOHNSON L. (3); SOSA V. (4) and COCUCCI A.A. (1) Instituto Multidisciplinario de Biología Vegetal (IMBIV), CONICET-Universidad Nacional de Córdoba (2) Instituto Multidisciplinario de Biología Vegetal (3) Department of Integrative Biology, BYU, USA (4) Instituto de Ecología, A. C., Xalapa, México *andreacosacov@gmail.com Understanding the patterns and processes associated with geographical variation in population genetic and phenotypic structure across a species range is motivated by conservation concerns and constitutes an important issue in evolutionary ecology. Recent reviews provide weak support to the accepted central-margin model. This could be the result of a preponderant effect of historical events in determining range-wide genetic structure. However, almost no study has incorporated a phylogeographical framework; therefore we report our phylogeographical study of Calceolaria polyrhiza , a perennial herb endemic to Patagonia, for the evaluation of this hypothesis. We used cpDNA sequences from 590 individuals sampled from 68 localities, in the Andean forests and Patagonian steppes, covering all the species range. We tested the central-margin hypothesis at the whole species level and at different levels of the genealogy, using the geographically bounded, monophyletic lineages within the species, as independent replicates. We analyzed the geographic structure of genetic and phenotypic (i.e. variation coefficient of 14 functional phenotypic traits) variability. In general, at lower levels of the genealogy results support the central-margin hypothesis while at higher levels the effect of allopatric fragmentation, secondary contact and Pleistocene refugia dilute these patterns. The associated geographical trends in neutral and quantitative phenotypic trait variation are also discussed. Genetic diversity in populations of Chusquea (Bambusoideae, Poaceae) of the Venezuelan Andes ELY F.* and FERMIN G. Universidad de Los Andes *fely@ula.ve Chusquea is the most diverse genus of woody bamboos in montane ecosystems. In the Venezuelan Andes, Chusquea purdieana, C. serrulata and C. spencei represent the bamboos with the broadest distribution range. The first two species are associated to cloud forests, and the third to the páramo treeline. Although it might be particularly interesting to analyze distribution patterns in bamboos due to their clonal propagation, very few phylogeographic studies have been carried out so far. Therefore, the purpose of this research was to study the genetic diversity in these three species, using molecular markers that targeted ISSR, RAPD and SSR loci. The sampling was carried out along altitudinal gradients between 2.000 and 3.650 masl in the Cordillera de Mérida. Fresh leaf samples were collected from genets separated 50 m at different altitudes in each locality. After DNA extraction and quality verification, markers were amplified separately, and PCR products were visualized in 1.5 % agarose gels. Only clear and reproducible bands were tallied to generate binary matrixes that were analyzed with POPGEN32 and ARLEQUIN. These three species present an elevated genetic diversity; both within and among populations, regardless habit or habitat. This diversity was evident by the number of polymorphic loci, proportion of heterozygotes per population, and the absence of dominant genotypes in all of the populations sampled. Our findings suggest that none of the populations are of clonal origin. Population structure and phylogeography of the pumkin Cucurbita moschata FLOREZ-RUEDA A.M.* and MUñOZ-FLOREZ J.E. UNIVERSIDAD NACIONAL DE COLOMBIA *anmflorezru@unal.edu.co As part of a thesis dissertation which main objective is to establish the possible center or centers of origin of Cucurbita moschata, having into account the genealogical relationships of haplotipes and its association with its geographic distribution. Preliminary results are presented in the search for highly variable genomic regions at intraspecific levels in the species. Three nuclear regions ITS, G3PDH and Adh; and five cloroplastic regions rpl32-trnL, ndhF-rpl32, 3’rps16–5’trnK, trnQ-5’rps16, 3’trnV-ndhC and psbA-trnH were examined. The criteria for the selection of the regions for the complete analysis were: amplification success, and high level of polymorphism. The Adh region couldn’t be amplified. The G3pdh and trnQ (UUG)-5’rps16 regions amplified more than one band. All the other regions had successful amplifications and were sequenced. The bioinformatic analysis of the sequences allow the determination of Number of polymorphic (segregating) sites and Nucleotide diversity values, that showed that rpl32-trnL and ITS are the most variable regions at intraspecific level and will be used in the phylogeographic study that will contribute to the study of the evolution of this species. The role of triploids on the origin, establishment and coexistence of tetraploids with diploids in natural populations of Turnera sidoides autopolyploid complex KOVALSKY I.E.* (1); ELíAS G. (2); MORENO S. (1); PANSERI A. (1) and SOLíS NEFFA V.G. (3) (1) Instituto de Botánica del Nordeste (UNNE- CONICET). CC 209. 3400, Corrientes (Argentina) (2) Instituto de Botánica del Nordeste (UNNE- CONICET). CC 209. 3400, Corrientes (Argentina). (3) Instituto de Botánica del Nordeste (UNNE- CONICET). CC 209. 3400, Corrientes (Argentina) and Facultad de Ciencias Agrarias (UNNE) *evelinkov@hotmail.com Theory suggests that the evolution of autotetraploids within diploid populations is opposed by a minority cytotype mating disadvantage, since rare tetraploids incur in a larger portion of hybrid matings that yield inviable triploid progeny (triploid block). Turnera sidoides (x=7) is used as a model system to evaluate the role of triploids on autotetraploid evolution in natural populations. This complex of perennial rhizomatous herbs is widely distributed in southern South-America and shows ploidy levels from diploid to autooctoploid. The finding of triploids in natural populations and in experimental crosses evidences a lower triploid block in this species. Thus, our objectives were to: 1) estimate the frequency of neopolyploids in diploid populations and analyze their mechanism of origin; 2) evaluate the frequency and distribution of cytotypes in two diploid-tetraploid contact zones; 3) estimate fecundity and offspring ploidy in matings among diploid, triploid and tetraploid in all possible combinations. The finding of 3.5% triploid embryos contrasts with the rarity of triploid plants observed in natural diploid population. The 2n gametes involved in triploid formation were mostly of paternal origin. Within the contact zones, spatial segregation of cytotypes was seen although, mixed 2x-3x populations were also found. Triploids produced x or 2x euploid gametes in equal proportion, however no tetraploid offspring resulted. The results obtained suggest that in T. sidoides although triploids can potentially contribute to the formation of tetraploids by a triploid bridge as well as to the maintenance of the current cytotype distribution within the contact zone, the contribution to tetraploid establishment is minor. Genetic variability in grass species along a latitudinal gradient in Patagonia. LEVA P.E. (1); AGUIAR M.R. (1) and PREMOLI A.C.* (2) (1) Cátedra de Ecología, IFEVA (FAUBA-CONICET) (2) Univ.Nac.del Comahue, Laboratorio Ecotono (CRUB) *pleva@agro.uba.ar Our research program studies genecology of Bromus pictus and Poa ligularis two native forage species threatened by sheep overgrazing. Our specific objective was to compare genetic diversity and divergence among and within 6 populations of each species distributed along a latitudinal gradient (ca. 600 km). Leaves from 30 randomly selected individuals from each population were analyzed by isozyme electrophoresis. We estimated genetic variability indexes (Pss, At, Ap, Ar(10%), A, Ae, I, Ho, He) and genetic divergence (distribution of alleles frequencies and Wright’s F statistics). Analysis showed that 8 and 13 loci were polymorphic out of 9 and 19 resolved loci in at least one population for Bromus and Poa , respectively. In both species, rare alleles (<10% frequency), followed a latitudinal pattern, decreasing from south to north. Genetic divergence among populations was significant in both species (FST = 0.128 Bromus, FST = 0.095 Poa). Analyzing our genetic and quantitative data-base (i.e. FST/QST index) we found evidence of local adaptation in populations of the two species. Using allelic frequencies we detected two different geographical groups divided at the same latitude in both species. Thus, biogeographic distribution may reflect some historical event that affected both species. At the species level, Poa showed greater genetic variability than Bromus, probably due to ecological differences (large geographic range and dioecious mating system). Spatial genetic structure of Aechmea nudicaulis (Bromeliaceae) at Jurubatiba Restinga National Park (Macaé, RJ, Brazil) LOH R.* (1); SALGUEIRO F. (2); ALVES-FERREIRA M. (1) and SCARANO F. (1) (1) Universidade Federal do Rio de Janeiro (2) Universidade do Rio de Janeiro *robertakuantchuen@gmail.com Aechmea nudicaulis is a bromeliad typical of the Jurubatiba Restinga National Park, where plant community is organized in natural groups called vegetation islands with a central species creating suitable conditions for other species to establish. A. nudicaulis is one of the few species observed both within and outside the islands. Our hypothesis is that A. nudicaulis germinates within the islands and grows away from its center by clonal reproduction so that individuals surrounding a definite island would be genetically very similar. The goal was to evaluate the spatial genetic structure of the population and verify if it followed the structure of vegetation organization. Individuals were sampled in 18 islands separated by distance classes ranging from 10m to 3000m. Genetic profile of individuals was revealed by 103 polymorphic AFLP loci. Statistical analysis was performed by AMOVA and spatial autocorrelation analysis. AFLP fingerprints revealed that most of the plants assessed were not consequence of clonal reproduction. The AMOVA results indicate a significant structure in the distribution of genetic variation (79% between islands and 21% within islands). The spatial autocorrelation analysis indicates that for individuals separated by up to 30m, reproduction does not occur at random. The Mantel test, comparing geographic distance with genetic distance between individuals, revealed a weak positive relation with individuals closer to each other being genetically similar. Estimation of mating system parameters and the pollen dispersal Kernel in Nothofagus nervosa MARCHELLI P.* (1); SMOUSE P.E. (2) and GALLO L.A. (1) (1) Unidad de Genética Ecológica y Mejoramiento Forest (2) School of Biological & Environmental Sciences, Rut *pmarchelli@gmail.com The extent of pollen flow, along with mating system parameters such as inbreeding coefficients and correlated paternity among progeny, determine the genetic structure of plant populations and are crucial for the design of conservation strategies. The objective here is to estimate mating system parameters and to fit the pollen dispersal kernel in Nothofagus nervosa. We sampled 25 mothers and 372 progeny, distributed in two groups, from the Tromen Lake region in Argentina. We registered spatial position of the maternal trees, and genotyped mothers and offspring for five SSR markers. We estimated single locus (ts = 0.95) and multilocus (tm = 0.99) outcrossing rates, biparental inbreeding (tm – ts = 0.04), and correlated paternity within maternal sibships (rp = 0.10) with MLTR software (Ritland 2002). We used KINDIST software (Robledo-Arnuncio et al. 2006) to fit an exponential power dispersal kernel to the structure of pollen clouds sampled by different mothers. The effective number of pollen donors to a single mother is Nep = 9.6. The average pollination distance is 32.4m, but the dispersal kernel is leptokurtic (b = 0.36). The pollination pattern was bimodally distributed, in accord with the two subgroups. Nothofagus nervosa is strongly outcrossing, has short average pollen dispersal distance, but has a high probability of long distance dispersion. Phylogeography of Gentianella magellanica , an endemic plant from southern South America MARTINEZ C.* University of Edinburgh *camilamartineza@hotmail.com Aims. Establish locations of plant refugia and post glacial colonisation routes in Patagonia and assess if refugia were located in northern Patagonia (Coastal Cordillera and northern Andes), or whether there is evidence for scattered central and southern Patagonian refugia. Methods. Genetianella magellanica (Gentianaceae) is a widely distributed annual with gravity dispersed seeds. In northern Patagonia it occurs in isolated populations, but is more common in southern Patagonia. To establish the distribution of phylogeographic lineages 5 individuals from 12 populations were sequenced for the chloroplast regions PsbA-TrnH and TrnD-TrnT. Relationships among haplotypes were explored using a minimum spanning tree. Results. Coastal and Northern Andes populations are phylogenetically divergent from each other. All southern populations are closed related. They show greatest phylogenetic affinity with the central Andean population. Conclusions. The presence of phylogenetically divergent populations isolated on northern mountains is consistent with their origins from different northern refugia. The locations of these populations correspond to previously inferred refugia from fossil pollen data. In contrast, the high genetic similarity among the widely distributed southern populations is consistent with origins from a single refugium. The affinity between the southern populations with those in the central Andes may be attributable to shared ancestry from a southern or central Andean refugium. Adaptive and plastic responses of Nothofagus pumilio with elevation MATHIASEN P.* and PREMOLI A.C. Universidad Nacional del Comahue - CONICET *pmathiasen@gmail.com Contrasting conditions along altitudinal gradients impose differential selection pressures over plants which may show adaptive and plastic responses. Many of the differences found at contrasting altitudes in the dominant tree of high-elevation forests Nothofagus pumilio, were demonstrated to have a genetic basis. The objective is to evaluate the adaptive nature of these differences at contrasting elevations. A reciprocal transplant experiment of N. pumilio seedlings was performed in Challhuaco Valley at 41°S latitude, Argentina. In the year 2005, 220 seedlings from low and high elevation were reciprocally transplanted and monitored during three consecutive growing seasons. Measurements of growth, mortality, leaf morphology, and phenology were recorded. Our results show that plant origin determines growth habit. Plants from high altitude seedlings never overgrew low altitude ones, suggesting genetically fixed responses. In contrast, low altitude seedlings attained greatest plant height under extreme conditions in high altitude as a result of plasticity and/or greater genetic diversity. We found a significant effect of elevation for most leaf traits. Also, leaf characters at low elevation differed between origins suggesting significant genetic controls. Similarly, phenology yielded fixed genetic responses. The results from this study show adaptive and plastic responses of N. pumilio which will allow local survival to changing environmental conditions in Patagonia. Genetic characterization of a Calophyllum brasiliense Camb. (Clusiaceae) population from San Ignacio, Misiones-Argentina PERCUOCO C.B.*; BICH G.A.; RODRÍGUEZ M.E.; CARDOZO A.E. and ARGÜELLES C.F. UNIVERSIDAD NACIONAL DE MISIONES *ceciliapercuoco@gmail.com C. brasiliense, “arary”, grows exclusively in riparian forest. Its geographical distribution extends from Mexico to the south region of Brazil and Paraguay, being recently cited for Misiones and Corrientes, Argentina. These populations are under a fragmentation process, and in risk of permanent flood. The aim of the present work was to characterize the genetic diversity of an arary population from San Ignacio, using RAPDs markers. Leaf tissue was collected from 30 individuals. The DNA extraction was carried out according to the protocol developed by Stange et al. (1998), with modifications. Twenty commercial primers were tested in order to select reproducible and informative patterns. Population parameters were estimated using POPGENE software. Four out of the twenty primers tested gave clear and reproducible band patterns. Thirty six of them were identified as molecular markers, from which 78% expressed polymorphisms. The diversity indexes were under 0.3, being low in comparison with other populations of tropical tree species. This scarce genetic diversity observed may reflect an effect of past bottlenecks. It is necessary to characterize the population through other molecular markers like SSRs or ISSRs. Furthermore, it seems interesting to incorporate populations from Corrientes to strengthen these results as well as to guide decisions that deal with conservation of the arary‘s remnants. Molecular and morphological differentiation among varieties of A. caven by means of discriminant analysis POMETTI C.L.* (1); VILARDI J.C. (2); CIALDELLA A.M. (3) and SAIDMAN B.O. (2) (1) Fac. de Cs. Exactas y Naturales, Universidad de Bs. As. (2) Fac. de Cs. Exactas y Naturales, Universidad de Bs (3) Instituto de Botanica Darwinion *cpometti@ege.fcen.uba.ar Six varieties of A. caven have been described based on morphologic traits of the fruit: caven, macrocarpa, dehiscens, sphaerocarpa, stenocarpa and macrocarpa. In this study, we conducted a parallel analysis of genetic and phenotypic diversity among and within the six varieties of A. caven with the objective of determining if the varieties described on morphological grounds represent genetically differentiated entities. The distinction of the six varieties was examined using morphological and RAPD markers. We studied 15 Argentinean populations. The data obtained by both methodologies was analysed by means of discriminant analysis (DA). A total of 47 RAPD bands were generated with the 5 chosen primers across 224 individuals. DA indicated that both, populations and varieties can be differentiated on the basis of RAPD band patterns (P< 10-4). The results of the DA from morphological data were according with those obtained with RAPD, and the discrimination of varieties from morphological traits was also highly significant (P< 10-4). The results of this work show a consistency between the prior classification of individuals in varieties and the posterior classification based on molecular markers and our results support the taxonomic differentiation of the six varieties studied. Geographic range effects on the genetic characteristic of two southern South America Podocarpus species. QUIROGA P.* CRUB-INIBIOMA *emepequ@gmail.com Plant genetic variation presents high association in relation to geographic range. However, climatic events of the Quaternary could have differentially affected genetic characteristics of widespread South American Podocarpus. I studied levels of isozyme variation in relation to geographic range and population continuity. I analyzed 14 and 18 populations of P. nubigena and P. parlatorei using 12 and 14 isozyme loci, respectively. For each species, population diversity parameters and among-population divergence was estimated. Mean within-population polymorphism and diversity (PSS and HE) were high although statistically different between species: Podocarpus nubigena PSS=65 and HE=0.218, whereas P. parlatorei presented PSS=43 and HE=0.151. Degree of divergence was FST=0.181 and 0.109 among populations of P. nubigena and P. parlatorei which can be explained in relation to Quaternary climatic events. Thus, P. nubigena could have suffered restrictions for gene flow during glacial periods due to the presence of different genetic variants in several populations. On the other hand, P. parlatorei has probably expanded its range and also populations have maintained high rate of gene flow promoted genetic homogenization of populations. Conservation genetics of the paper tree in Ecuador (Polylepis, Rosaceae) SEGOVIA-SALCEDO C.* (1); QUIJIA P. (2); PROANO-TUMA K.; SOLTIS D. (1) and SOLTIS P. (1) (1) University of Florida (2) Escuela Politecnica del Ejercito *claudia@ufl.edu Studies on the conservation of the Polylepis forest are being carried out in Ecuador. Ecological and genetic information is being collected to address conservation genetic questions to define the level of hybridization among species of this genus, the impact of introduced species on the genetic identity of local species and the genetic uniqueness of the Ecuadorian species. Twenty-nine populations were sampled, corresponding to the eight Ecuadorian species, with three populations suspected to be products of hybridization. The design of microsat primers using a microsatellite enrichment procedure has been carried out. Forty-eight markers were isolated for amplification of polymorphic microsatellite loci for the genus Polylepis. These markers have been evaluated in 18 individuals from 6 different species. In addition, chromosome counts of Ecuadorian species using root tips, and flowers or plants maintained in the greenhouse had been done. Results indicated that Ecuadorian species of Polylepis had between 36-102 chromosomes. Variation among chromosome number from different populations from the same species is reported for P. incana, P. reticulata, and P. sericea, many of them possible polyploids. This study is the first to report chromosome numbers for this genus due to their small size. A more detailed survey of different locations is needed. Cytological information provided clues about Polylepis’ ancestry and relationships. Biodiversity and genetic patterns of Austrocedrus chilensis stands mirror fire history of drylands of Patagonia SOUTO C.P.*; HEINEMANN K.; KITZBERGER T. and PREMOLI A.C. Lab. Ecotono-Inibioma-Conicet-Universidad Nacional *csouto@crub.uncoma.edu.ar Species and genetic diversity as distinct levels of biological hierarchy are rarely analyzed concomitantly despite the recognition of their conceptual unification in biodiversity and ecological evolutionary research. In northwestern Patagonia Argentina fire has been proved to have a major influence on vegetation patterns. Austrocedrus chilensis is the dominant native conifer displaying a SW-NE gradient of increasing fragmentation. We tested the hypothesis that fire history has shaped genetic traits within populations of A. chilensis as well as the composition of vegetation matrix where they are embebed. We sampled 1853 individuals in 67 populations between 37 and 42°S lat in Argentina. We measured genetic diversity and inbreeding within populations on the basis of 12 allozyme loci, scoring accompanying species along transects. Species richness increased southwards (&#946;= +0.28; p= 0.02), with the opposite pattern in genetic diversity (&#946;= -0.41; p= 0.0006). Inbreeding was high and positive (Fis> 0.14) in northern and central-eastern populations of Austrocedrus, while non-significant inbreeding was evident in less genetic variable southern and central-western populations (Fis< 0.06). These results agree with accompanying species ordination showing differences in species composition among these two areas. Our results mirror a long pre-European history of small and frequent fires in the northeast and more recent (settlement age) extensive stand-devastating fires towards southwest. Differentiation genetics distribution of Anarthrophyllum rigidum , Patagonia, Argentina. SRUR A.* (1); ARBETMAN M. (2); PREMOLI A. (2) and VILLALBA R. (1) (1) IANIGLA-CCT Mendoza- CONICET (2) Lab. de Ecotono. Univ. Nac. Comahue. Bariloche *asrur@mendoza-conicet.gov.ar Anarthrophyllum rigidum is a shrub species of wide distribution in the Patagonian steppe finding from the South of Mendoza until Santa Cruz. This species is forming patches of different sizes and under changing environmental conditions. So is that it is between the 1990 and 170 m above sea level in areas where the predominant soil is rocky until sectors with sandy soils. Anarthrophyllum rigidum presents also a high variability in its architecture to the amount of stems, height and diameter of the crown, etc. With the end of complement ecological studies is that base sequences of the chloroplast not coding region trnQ/rps16, were analyzed 31 individuals collected of the distribution of Anarthrophyllum rigidum. The sequenced fragment had 413 pb with three informative sites resulting in six different haplotypes. Greater diversity found North studied distribution, with a common haplotype in the range. One of the Andean population analyzed North distribution presented a unique and divergent haplotype from the rest of the found haplotypes. These results allow provide data to understand the history the species biogeographical. Bromelia antiacantha : genetic structure, morphology and ethnobotany ZANELLA C.M.*; PAGGI G.M.; BRUXEL M.; GOETZE M. and BERED F. Universidade Federal do Rio Grande do Sul *milamzanella@yahoo.com.br Bromelia antiacantha (Bromeliaceae) is found in moist soils of forest and secondary vegetation. It ranges from eastern Brazil to Uruguay. It is a polyploid species, partially self-incompatible, with high clonal reproduction. The fruits are edibles berries with phytotherapic properties which have been commonly used in folk medicine in the preparation of syrup for breathing problems. Knowledge of genetic structure, morphology and ethnobotanical survey provides crucial data for sustainable management and to make use of these resources. We use five nuclear microsatellites to study patterns of population structure in seven populations along the coastal lowland of southeastern Brazil, totalizing 167 individuals sampled. All five SSR loci were polymorphic, indicating high expected heterozygosity (HE = 0.705), with strong population structure (GST = 0.219) and high coefficient of inbreeding (FIS = 0.539). Populations of B. antiacantha displayed great phenotypic diversity for the ten traits evaluated; however there was no clear identity considering each population. Ethnobotanic survey showed that people use the plant mainly for preparing syrup for respiratory diseases. B. antiacantha has great potential to be explored as phytotherapic resources, showing high seed viability and clonal reproduction. The species presented high genetic diversity among populations, which is an important factor that must be considered for species conservation and selection genotypes for cultivation.