Bright orange with three distinctive white bars, the Clown Anemonefish (Amphiprioninae) featured in Finding Nemo reach about 4.3 inches in length, and live in the shallow waters of the Indian Ocean, Red Sea, and western Pacific.
Clownfish are named after the sea anemone in which they make their home. Until acclimated to its toxin, they gently touch the anemone’s tentacles with their mucus-covered skin, then repay their host for safe harbour by discouraging intruders and removing parasites.
However, the most startling fact is that all clownfish are born male in a hierarchical group dominated by a single reproducing female. In the event of her death, the largest male changes sex to become female. This is irreversible.
Despite the ratio of males in the group the female is not polygamous. To ensure that the dominant male is not threatened, the others purposefully modify their growth rate to remain small and submissive, and thus protect themselves from eviction.