Story highlights Researchers estimate Greenland sharks live at least as long as 400 years

These Arctic sharks reach sexual maturity around the age of 150, according to a study

(CNN) Swim aside, bowhead whales: Greenland sharks have stolen the crown as longest-living vertebrate on Earth. University of Copenhagen researchers estimated that these sharks live at least 400 years, nearly two centuries longer than the whales.

A student job with the Greenland Institute of Natural Resources inspired Julius Nielsen, lead author of the new study, to research the Greenland shark, which roams the chill waters of the North Atlantic. "I encountered the sharks here for the first time, and I was fascinated that so little were known about such large sharks," Nielsen said.

They are the largest fish native to Arctic seas, with adults typically measuring between 13 and 16 feet and females consistently outgrowing the males.

Still, their biology was mostly a mystery, explained Nielsen. "For example, their age was unknown but expected to be great," he said, based on studies from more than 50 years ago. The extremely slow growth rates of these sharks -- less than a centimeter per year -- suggested they must live for many years."

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So how do you discover the age of a mute primordial shark? Nielsen and his colleagues turned to radiocarbon dating.

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