A Greenland shark can live up to 500 years—longer than any other shark species. “Some Greenland sharks could have been around since before the formation of the United States,” says Ewan Camplisson, a biologist at the University of Manchester in England. “We wanted to understand what adaptation allows them to live so long.” Camplisson’s team decided to investigate the Greenland shark’s metabolism—the chemical processes in an organism’s body that generate energy to sustain life.
Normally, when animals age, their metabolism slows down and gets worse at generating energy. Without this energy, the body starts to lose strength and speed, and can’t recover as easily from injury or disease. After analyzing tissue samples from Greenland sharks at different ages, Camplisson’s group discovered that the sharks’ metabolism didn’t slow down over time. This unchanging metabolism could be the key to the animals’ incredibly long lives.