Scientists have now found a female Greenland shark that is older than the United States.
Researchers from the University of Copenhagen used radiocarbon dating to determine the ages of 28 of the sharks and estimated one female was about 400 years old, making it the longest living vertebrate in the world.
That would mean that particular shark was born 159 years BEFORE the American revolutionary war. Talk about a senior citizen discount.
The Greenland shark now boasts a longer life-span than a bowhead whale, the former record holder, which was estimated to be 211 years old.
The researchers found that the sharks grow just 1 cm a year and don't reach sexual maturity for about 150 years.
Greenland sharks are the largest fish in the Arctic seas. Adults typically measure between 13 and 16 feet long. Female Greenland sharks usually outgrow the males.
They swim slowly, presumably to conserve energy, in the deep waters of the North Atlantic.
Julian Nielsen, the lead author of the study told the BBC, "We had our expectations that we were dealing with an unusual animal, but I think everyone doing this research was very surprised to learn the sharks were as old as they were."
Researchers examined the eye lenses of the sharks that had been caught in scientific surveys to determine their age.
Deepwater sharks, also called "sleeper sharks," are extremely hard to study and scientists have had little success determining their age until now.
But the Greenland shark is still not the oldest animal. When invertebrates are brought into the competition, a 507-year-old clam called Ming hold the title of oldest animal.
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