Marine biologists at the National Oceanic and Atmospheric Administration in San Diego, California have recently made a stunning discovery. Nicholas Wegner, a fish physiologist, has proved that the Opah (or Moonfish) generates heat from its massive pectoral muscles and conserves it thanks to body fat and the special structure of blood vessels in its gills despite living in deep, cold water. This makes the Opah the first ever warm-bodied fish discovered in our oceans.
The higher body temperature provides the Opah with several advantages over his cold-blooded fellow fish, including more powerful swimming and better endurance, thanks to the warm heart.