| Online: | |
| Visits: | |
| Stories: |
First warm-blooded fish discovered off California
Shayne Jacopian for redOrbit.com – @ShayneJacopian
NOAA Fisheries biologist Nick Wegner holds an opah caught during a research survey off the California Coast. (Credit: NOAA Fisheries/Southwest Fisheries Science Center)
While conducting research off the coast of California recently, NOAA Fisheries scientists discovered that the opah, or moonfish, is the first fully warm-blooded fish. Capable of circulating heated blood throughout its body like mammals and birds, it has a distinct advantage as a predator living in the coldest, deepest waters.
Other fish inhabiting these chilly ocean depths are often slow and sluggish, preferring to ambush rather than chase their prey, with the exception of some much larger predatory fish, like tuna, which can temporarily warm some muscles and organs during pursuit. The moonfish, however, can generate heat by flapping its pectoral fins. This flapping does more than just heat the surrounding muscles, though; it heats a “retia mirabilia”, best described as a net of densely packed blood vessels. In turn, it heats the blood that gets distributed to the rest of the fish’s body.
Nicolas Wegner, lead author of the research, first noticed something different about the moonfish when a coauthor of the study, Owyn Snodgrass, collected a sample of gill tissue. In the gill tissue were blood vessels that carried warm blood into the gills, intertwined with vessels carrying cold blood back to the body, where it’d been heated by the ever-flapping peck fins and distributed throughout the fish’s body.
As a result of having a warmer heart and brain—about five degrees Celsius higher than ambient temperatures—the opah swims faster and with more agility, reacts more quickly, and has better vision than most other predatory fish inhabiting frigid waters. This gives it a distinctive competitive edge over other predators, which can often be far larger than the opah, which is about as large as a car tire.
“Nature has a way of surprising us with clever strategies where you least expect them,” Wegner said. “It’s hard to stay warm when you’re surrounded by cold water but the opah has figured it out.”
And with that, we’ll let it ride out:
—–
Follow redOrbit on Twitter, Facebook, Google+, Instagram and Pinterest.
redOrbit.com
offers Science, Space, Technology, Health news, videos, images and
reference information. For the latest science news, space news,
technology news, health news visit redOrbit.com frequently. Learn
something new every day.”
Source: http://www.redorbit.com/news/science/1113391632/first-warm-blooded-fish-discovered-off-california-051515/
