The first warm-blooded fish has been identified in the Pacific Ocean by researchers from the National Oceanic and Atmospheric Administration.
Traditionally, fish and reptiles are not known to create their own body heat. Instead, they draw heat from their surrounding environment — this is why we call these animals “cold-blooded”.
Though some fish can temporarily warm their bodies, up until now full-body endothermy (ie. temperature control) was thought to be exclusive to mammals and birds.
But this is no longer the case. According to Popular Science…
“Unlike their cold-blooded friends, opah generate heat as they swim, distributing the warmth throughout their bodies via special blood vessels. Their unique gills minimize heat loss, allowing them to stay warm even 250 feet below the surface.”
The discovery was published in Science Magazine’s May issue. In their report, the team describes the unique attributes that allow the opah fish (Lampris guttatus) to create its own heat. According to the researchers, the fish mainly generates heat through the flapping of its fins, and maintains this heat using specialized insulating gills.
Check out the video below from CNN to learn more about the First Warm-Blooded Fish…