Meet the world's first fully warm-blooded fish


It's called an opah, and scientists in the journal Science say it maintains a warm temperature throughout its entire body by "continually flapping [its] wing-like pectoral fins," according to Newsweek.
It also looks like giant goldfish:
National Geographic points out that other big fish, like tuna and sharks, can warm some parts of their body when they swim vigorously. But they can't compare to the opah, whose warm-bloodedness enables it to move faster than its competitors.
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Ryu Spaeth is deputy editor at TheWeek.com. Follow him on Twitter.
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