Heatwaves cause clownfish to shrink, study reveals

Researchers have discovered that clownfish shrink in size during marine heatwaves. The study, published in Science Advances, observed 134 clownfish in Papua New Guinea. During a heatwave, 100 of these fish exhibited significant shrinkage, likely as a survival mechanism. The phenomenon is linked to both temperature stress and social hierarchy within clownfish groups.

Female clownfish, which dominate their groups, were less likely to shrink if they were only slightly larger than their male counterparts. The study suggests that shrinking may reduce food and oxygen needs, improving survival rates in warmer waters.