OPAH IS THE FIRST FISH FOUND WITH A WHOLE-BODY ENDOTHERMY
Of all the fish in the world, only a few have the ability to keep warm in certain parts of their bodies. But new research reveals that opah (Lampris guttatus) have the ability, unprecedented, of circulate warm-blood throughout the body, so it is the only known fish that has warm-blood.
The ability to generate heat internally is what distinguishes birds from mammals and fish. So far, only some predators, such as tuna, have demonstrated the ability to heat certain muscles and organs while chasing their prey, but they have to return to the surface to increase the temperature of the rest of its body.
According to researchers Lampris guttatus mainly increases its body temperature through constant flapping of its pectoral fins
Werner, who leads the study adds that opah has specialized blood vessels in their gills, forming countercurrent heat exchangers to minimize this loss of heat to the water when the fish breathe .
An advantage of constant heating of the fish is seen in improved performance. “A hot cranial region allows opah to increase reaction rates and visual resolution. This is important when these fish look for food in the cold, deep waters, where they spend most of their time, "remarks Wegner.
Reference: Wegner et al. 2015 “Whole body endothermy in a mesopelagic fish, the opah, Lampris guttatus” Science
Photo: NOAA Fisheries/Southwest Fisheries Science Center











