The clownfish or anemonefish has a unique relationship with several South Pacific sea anemone species. It is the only fish that is not harmed by the venomous sting of the anemone. Clownfish lay their eggs under the overhang of an anemone’s tentacles. The eggs are protected from predators and in addition, a special mucus is transferred from the anemone to the eggs. The mucus plays a part in chemically directing the juvenile fish back to the anemone. Anemones are nonmotile; they do not move. If this is a mutualistic relationship, how does the clownfish help the anemone?