Clownfish, wrasses, moray eels, gobies and other fish species are known to change sex, including reproductive functions. A school of clownfish is always built into a hierarchy with a female fish at the top. When she dies, the most dominant male changes sex and takes her place.
Clownfish live at the bottom of the sea in sheltered reefs or in shallow lagoons, usually in pairs. Clownfish have a special relationship with the anemone and are very important to them. They are a large help to the anemone as they clean the anemone by eating the algae and other food leftovers on them.