Peer pressure can make this clownfish change its stripes

"Tomato clownfish, in response to an unpredictable world, appear capable of flexibly adjusting when they lose their stripes based on cues from other fish and their habitat. In particular, the presence of a pair of adult tomato clownfish on a real anemone accelerates the fading of the stripes, suggesting that young fish may alter their physical appearance to help them find a foothold in the local social hierarchy."

"Juvenile tomato clownfish, which are just a couple weeks old, have two to three white stripes—a head bar, a body bar and, sometimes, a tail bar. At least, that's how they start out when they're settling onto an anemone for the first time and joining a strictly enforced pecking order of the older tomato clownfish already there."

Tomato clownfish undergo a dramatic physical transformation as they mature, losing most of their juvenile stripes to retain only a single head stripe in adulthood. Researchers discovered this stripe loss is triggered by both environmental and genetic factors. Young fish appear to strategically time their stripe fading based on social cues from adult clownfish and habitat conditions. The presence of adult tomato clownfish on an anemone accelerates stripe loss in juveniles, suggesting young fish modify their appearance to establish their position within the strict social hierarchy of their anemone community. This adaptive response helps juveniles integrate into established social groups.

Read at www.npr.org