Fish were long believed to be unfeeling, dead-eyed animals. But now scientists are discovering the intrinsic social life of fish. They grieve, engage in cooperative hunting and some have very weird sex lives. Take an underwater journey to learn more about the greatly misunderstood and underappreciated fish.

Fish have each other’s back. The rabbit fish even go out for lunch together: While one of them feasts on the algae found on deep-water reefs, the other is on the look out for predators. Then they switch. Scientists call this virtuous behavior. The rabbit fish make sacrifices for another by waiting their turn.

It was long believed that fish cannot feel fear because they’re missing the part of the brain where other animals and humans process it. But scientists have now shown that fish do feel fear, pain and stress. It is still a contested issue among researchers, though. Fish welfare lobbyists say the new findings are an inconvenient truth as it means we would need to rethink our fishing practices.

Those lush lips look like they are made for smooching! One fish species goes even further and uses their mouths to procreate. The female drinks the male's sperm which passes rapidly through the intestinal systems and fertilizes the eggs. It’s a pretty weird sex practice not often observed in the animal kingdom. But the red-lipped batfish pictured here actually procreates the traditional way.

The world-famous clown fish are very social creatures: They share their anemone homes with other fish. The venomous anemones offers life-saving protection to the little fish, as they are immune to its sting. As a result, it often gets a bit tight in their cozy homes.

The mean-looking grouper cooperates with the moray eel while hunting. The grouper initiates the hunt by shaking its head at the eel. The eel then follows it to the prey hiding in a hole and enters the hide-out. It's a 50/50 chance whether the eel corners and eats the prey or it escapes out of the hole into the grouper's mouth. This kind of team effort is extremely unusual in the animal kingdom.