The world’s first fully warm-blooded fish has been found, according to anew study published in the journal Science.
The opah fish are incredibly quick, have excellent vision and amazing stamina, making it one of the most deadly predators in the sea.
“Before this discovery I was under the impression this was a slow moving fish, like most other fish in cold environments,” said study author Nicholas Wegner, fisheries biologist at the NOAA Fisheries’ Southwest Fisheries Science Center in La Jolla, in a statement.
“But because it can warm its body, it turns out to be a very active predator that chases down agile prey like squid and can migrate long distances.”
Wegner said that he first noticed blood vessels in the fish’s gills, which then returned cold blood full of oxygen back to the fish’s core.
The warm blood heats the cold blood making the fish 41 degrees Fahrenheit warmer than the water in which it swims.
It’s constantly flapping of its gills making it quick, which also keeps the fish warm in deep, dark waters. While sharks and tuna have semi-warm blood that allows them to move quickly in cold water, the opah is apparently one-of-a-kind.
“There has never been anything like this seen in a fish’s gills before,” Wegner said in the statement.
“This is a cool innovation by these animals that gives them a competitive edge. The concept of counter-current heat exchange was invented in fish long before we thought of it.”
These fish are primarily caught off the coast of Hawaii.
By ALEXANDER BESANT | ryot.org