The longest lived vertebrate takes the title by at least a century

Imagine having to wait a century to have sex. Such is the life of the Greenland shark—a 5-meter-long predator that may live more than 400 years, according to a new study, making it the longest lived vertebrate by at least a century. So it should come as no surprise that the females are not ready to reproduce until after they hit their 156th birthday.

The longevity of these sharks is “astonishing,” says Michael Oellermann, a cold-water physiologist at Loligo Systems in Viborg, Denmark, who was not involved with the work. That’s particularly true because oceans are quite dangerous places, he notes, where predators, food scarcity, and disease can strike at any time.

Greenland sharks (Somniosus microcephalus) had been rumored to be long-lived. In the 1930s, a fisheries biologist in Greenland tagged more than 400, only to discover that the sharks grow only about 1 centimeter a year—a sure sign that they’re in it for the long haul given how large they get. Yet scientists had been unable to figure out just how many years the sharks last.

Intrigued, marine biologist John Steffensen at the University of Copenhagen collected a piece of backbone from a  Greenland shark captured in the North Atlantic, hoping it would have growth rings he could count to age the animal. He found none, so he consulted Jan Heinemeier, an expert in radiocarbon dating at Aarhus University in Denmark. Heinemeier suggested using the shark’s eye lenses instead. His aim was not to count growth rings, but instead to measure the various forms of carbon in the lenses, which can give clues to an animal’s age.

Then came the hard part.

READ MORE

By Elizabeth Pennisi