Dingo the Dissident

THE BLOG OF DISQUIET : Qweir Notions, an uncommonplace-book from the Armpit of Diogenes, binge-thinker jottings since 2008 .

Monday, 18 September 2017

Long live sharks!


These Ridiculously Long-Lived Sharks Are Older Than the United States, and Still Living It Up


In an evolutionary sense, sharks are among Earth’s oldest survivors; they’ve been roaming the oceans for more than 400 million years. But some individual sharks boast lifespans that are equally jaw-dropping. Incredibly, deepwater sharks off the coast of Greenland appear to have been alive and swimming back in Shakespeare’s day 400-plus years ago—making them the longest-lived of all known vertebrates.

Bristlecone pines can live to be 5,000 years old. Sea sponges can live for thousands of years. One quahog, a hard-shelled ocean clam, died in 2006 at the age of 507. But among vertebrates, the long-lived skew much younger. Bowhead whales and rougheye rockfish can live for up to 200 years, and a few giant tortoises may also approach the two century mark.
Now it seems that Greenland sharks more than double even these remarkable lifespans, scientists report today in Science.
The reason for the sharks’ unfathomably long lives has to do with their lifestyles. Cold-blooded animals that live in cold environments often have slow metabolic rates, which are correlated with longevity. “The general rule is that deep and cold equals old, so I think a lot of people expected species like Greenland sharks to be long-lived,” says Chris Lowe, a shark biologist at the California State University at Long Beach. “But holy cow, this takes it to an entirely different level…”
(read more: Smithsonian Magazine)
photograph via: NOAA Okeanos Explorer Program

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