‘Nuclear bomb’ carbon dating shows Greenland shark can live for 400yrs (PHOTO)

©  Julius Nielsen / University of Copenhagen
Greenland sharks are living life to the max, with a study of the subarctic swimmers’ eyes indicating they can scour the oceans for nearly 400 years.

To put that in context, the estimate places the shark as the longest-living vertebrate, with a life-span dating back to the time of Shakespeare.

The creature previously holding that longevity record was the bowhead whale, but now one particular Greenland Shark appears to have blown that competitor out of the water... by almost 200 years. Also known as the ‘Gurry shark’, the Greenland predator can grow to 5 meters (16.4ft) in length, weighing somewhere in the region of 2,200lb.

The biology of the lethargic mover, which averages a speed of around a mile an hour, has remained something of a mystery. However, in a study of 28 female Greenland sharks, scientists from Denmark figured out a way to use dating techniques normally reserved for archaeological finds to estimate the shark’s life expectancy.

By combining carbon dating of shark eye lenses with the animal’s yearly growth rate, researchers from the University of Copenhagen were able to estimate a life span of at least 272 years. The study was led by PhD student Julius Nielsen and has been published in Science journal.

One of the animals featured in the research was 502cm in length, giving it an age of 392 years. It means the recently-deceased creature may have swam the oceans pre-1620.

However, the study does reveal a margin of error, give or take, 120 years. Even going by the lower end of the scale, though, the Greenland shark still beats other backbone animals in the age stakes.

Interestingly, researchers also examined two sharks which displayed “extra carbon,” that turned out to be the result of a “heavy isotope” entering the water via nuclear bomb testing, reports Science.

Nielsen and his colleagues also discovered that the shark doesn’t reach sexual maturity until the age of 150.

“Our lifespan study is based on the carbon-14 dating of Greenland shark eye lenses,”Nielsen explains. “As with other vertebrates, the lenses consist of a unique type of metabolically inactive tissue. Because the center of the lens does not change from the time of a shark’s birth, it allows the tissue’s chemical composition to reveal a shark’s age.”

“We use well-established radiocarbon methods, but combine them in a new way. This approach, along with the extraordinary ages for these sharks makes this study highly unusual.”