This 512-Year-Old Shark May Be the Oldest-Living Vertebrate Ever

Thursday, 14 December 2017 - 11:29AM
Weird Science
Earth
Thursday, 14 December 2017 - 11:29AM
This 512-Year-Old Shark May Be the Oldest-Living Vertebrate Ever
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A shark discovered in the North Atlantic off the coast of Greenland has stunned scientists. Researchers believe it may be 512 years old, making it the oldest-living vertebrate ever found. 

Researchers using a standby form of dating have revealed evidence proving the shark is one of, if not the, longest-living creatures on Earth.
 
Researchers determined the shark's age by using radiocarbon dating, which in this case turned up a startling point, chronicled by lead author and marine researcher Julius Nielsen, that "Radiocarbon dating of eye lens nuclei from 28 female Greenland shark (81-502 cm in total length) revealed a lifespan of at least 272 years." However, based on further research, many scientists believe the animal could be even older-
 
The Greenland shark is found across the North Atlantic Ocean, and at a typical length of over 14 feet, is the largest fish native to arctic waters that also hunts for nourishment there. 

The shark grows less than a centimeter a year, which they consider another hallmark of a long-lived creature—which would make sense for such a slow-grower to reach its expected length.

Researchers admit that "the biology of Greenland shark is poorly understood, and age at first reproduction and longevity is completely unknown." 
 
In what is probably not the prettiest discovery made about the Greenland shark, digested meals of polar bear carcasses have been found in the bellies of caught specimens. It's known to be a pretty open-minded eater, and will swallow pretty much anything that it can get into its mouth.
 
The animal has confounded researchers who have tried to work out the shark's aging potential, as it lacks calcified bones, in which the accumulation of calcium salts in a body tissue creates countable rings not entirely unlike rings found in tree stumps that can be used to determine age.

Nonetheless, it is a vertebrate, and one feature it does share with fellow spine-having animals is that the nucleus of its eye lens is made of metabolically inert crystalline proteins.

Their results "allow us to conclude that the crystalline formation in the lens nucleus almost entirely takes place around the time of birth, with a very small, and decreasing, continuous formation throughout life," wrote researchers, adding that the model they created enables them "to calculate the year of birth."
 
Knowing this, the Greenland shark researchers used radiocarbon datingthe dating of organic materials by measuring the content of carbon-14 present—and when integrated into a bevy of variables and physical attributes determined that "these findings seem to corroborate an estimated lifespan of at least 272 years for Greenland shark attaining more than 500 cm in length."
 
If this theory holds true, it could also mean that a shark found at longer lengths could be conceivably much greater in age, with some speculating that the specimen could be 512 years old. 

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This 512-Year-Old Shark May Be the Oldest-Living Vertebrate Ever
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