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Are all fish cold-blooded?

26 January 2017, 2:42 pm

Fisheries biologist Nicholas Wegner of NOAA Fisheries' Southwest Fisheries Science Center in La Jolla, Calif., lead author of the a 2015 research paper that discovered the unique warm-blooded characteristics of the opah (shown here).

Not all fish are cold-blooded. In 2015, researchers with the NOAA Southwest Fisheries Science Center revealed the opah, or moonfish, as the first fully warm-blooded fish. Although not as warm as mammals and birds, the opah circulates heated blood throughout its body, giving it a competitive advantage in the cold ocean depths from 150 to 1,300 feet below the surface.

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Original article: Are all fish cold-blooded?