Deep in the cold waters of the North Atlantic, the Greenland shark has been silently swimming for centuries. The Greenland shark is now known as the longest-living vertebrate on Earth. Recent scientific discoveries have revealed that these sharks can live for up to 400 years, making them one of nature’s most fascinating survivors. The study is published in the journal Science.
Scientists recently studied a female Greenland shark that measured 5 meters long and was likely born between the years 1501 and 1744. Using a special radiocarbon dating method on proteins in the shark’s eye lens, which remain unchanged from birth, researchers were able to estimate her incredible age.
“This shark could have been alive when Galileo was looking at the stars and when Shakespeare was writing his plays,” said Julius Nielsen, a marine biologist who led the study. “It’s hard to believe a living animal has seen so much history while quietly swimming in the depths of the ocean.”
The Greenland shark’s secret to longevity lies in its slow pace of life. These sharks grow at a rate of just about one centimeter per year and don’t even reach sexual maturity until they are around 150 years old. Living in the freezing waters of the Arctic and North Atlantic helps slow their metabolism, reducing cell damage and aging. This adaptation allows them to live for centuries in one of the harshest environments on the planet.
“They have a heartbeat of only about 10 beats per minute,” Nielsen explained. “Their blood moves slowly but efficiently, keeping them alive and healthy even in extreme conditions. Their bodies are built for patience and endurance.”
Despite their incredible resilience, Greenland sharks are facing serious threats. For centuries, they were hunted for their oil-rich livers, which were used in lamps and other products. This heavy hunting, especially before World War II, left their population struggling to recover. Today, most Greenland sharks swimming in the wild are still “teenagers” in shark years, not yet fully mature.
Marine conservationist Amanda Costello warned about the risks they face. “These sharks take such a long time to grow and reproduce. Any loss from fishing or accidental capture could take hundreds of years to fix. We have to protect them now if we want them to survive into the next centuries.”
The research on Greenland sharks has also uncovered details about their biology. Scientists discovered that their eye lens proteins are like time capsules, holding clues to the sharks’ birth dates. This technique allowed them to estimate that the oldest shark studied was likely about 400 years old, and possibly even older.
Some experts believe Greenland sharks could live even longer. One large female, measuring over 5 meters, could have been swimming in the icy waters when European settlers first arrived in North America. “We are only beginning to understand these sharks,” Nielsen said. “Their slow lives and long lifespans are unlike anything we’ve seen before in the animal kingdom.”
Greenland sharks are not just ancient; they are also apex predators. They feed on fish, squid, and even seals. However, their meat is toxic to humans because it contains a chemical that can cause serious illness if eaten raw. In Iceland, the meat is fermented for months to make it safe, creating a traditional dish called hákarl.
The sharks are also known for their mysterious habits. No one has ever seen them mate or give birth in the wild. Scientists believe they may carry up to 10 pups at a time and could have pregnancies lasting several years. But much about their reproduction remains unknown, making it difficult to predict how their population might recover.
Around 3,500 Greenland sharks are accidentally caught by deep-sea fishing vessels each year. Experts suggest using LED lights on fishing nets and banning deep gillnets in critical areas. These changes could save many sharks without hurting the fishing industry.
“Protecting Greenland sharks means thinking far into the future,” Costello added. “This is not about the next five or ten years. It’s about saving a species that might still be here in 2425.”
“They are like time travelers from the past,” Nielsen said softly. “If we lose them, we lose a living connection to our planet’s ancient history. We still have time to protect them, but we must act wisely.”
