Individual clown anemonefish shrink to survive heat stress and social conflict.

Vertebrate growth is generally considered to be unidirectional, but challenging environmental conditions, such as heatwaves, may disrupt normal growth patterns and affect individual survival. Here, we investigate the growth of individual clown anemonefish, , during a marine heatwave. We measured the length of 134 wild clown anemonefish every month and monitored temperature at the scale of their anemone for five lunar months.