The Greenland Shark's Secret and a Leopard That Hunted People

The Greenland shark can live for nearly 500 years, and scientists finally know why. A recent study found that these sharks show no change in enzyme activity between the ages of 60 and 200 years—their metabolism simply stays in equilibrium for over a century. While other animals experience metabolic slowdown as they age, the Greenland shark's enzymes remain constant, meaning its body processes nutrients the same way at 60 as it does at 200. This discovery explains the mechanism behind what researchers already suspected: cold environments, slow movement, and low energy expenditure correlate with extreme longevity.

Why the Shark Lives So Long

The Greenland shark's metabolic stability is directly tied to its environment and lifestyle. Living in frigid Arctic waters and moving at an extremely slow pace, the shark doesn't burn through energy the way warm-blooded animals do. The study revealed that the shark's body essentially enters a state of stasis—it doesn't shed and regenerate cells rapidly like humans do. Humans replace skin cells every seven years or so; Greenland sharks barely change at all.