- Greenland sharks can live up to 400 years, making them the longest-lived fish.
- Researchers are studying these sharks to uncover the secrets of their long lives.
- Understanding the longevity of bowhead sharks could improve human health and the study of aging.
Abigail Adams, wife of the second president of the United States, was born in 1744. It is entirely possible that there are Greenland sharks still alive today that were swimming in the North Atlantic at that time.
There is no doubt that these large carnivorous sharks can live for hundreds of years. In 2016, researchers found that they can survive for at least 272 years, but may reach 400 years.
But why these sharks have this kind of longevity is more of a mystery. Some theories include the shark’s slow growth rate and low metabolic rate, but research continues.
Scientists hope that unlocking the secrets of how these fish age could help people live longer and healthier lives. We probably won’t reach 400 years, but even extending the average human lifespan by an extra decade would be a breakthrough.
One scientist on the hunt is Ewan Camplison. He studies the metabolism of sharks for clues to the aging process.
“Better understanding the anatomy and adaptations of a long-lived species like the Greenland shark could allow us to improve human health,” Camlison, a PhD student at the University of Manchester, told Business Insider.
Slow metabolism throughout life
Found primarily in the Arctic and North Atlantic oceans, bowhead sharks are leisurely swimmers that can reach between 8 and 23 feet in length and weigh up to 1.5 tons, according to National Geographic.
Predators feed on salmon, eels, seals and even polar bears if they get the chance. However, they can probably go long periods between meals. According to a 2022 study, a 493-pound fish can do well on between 2 and 6 ounces of food per day.
Camplisson’s new research, which he presented at the Society for Experimental Biology’s annual conference earlier this month, showed that sharks’ metabolic rates may not slow as they age, which could help explain why sharks live so long.
The same is not true of most animals, including humans. For example, human metabolism tends to slow down in later years, which can contribute to unhealthy weight gain.
Camplisson examined the activity of five metabolic enzymes in preserved Greenland shark muscle tissue. “In most species, you would expect as the animal ages that the activity of these enzymes varies,” he said.
“Some of these will show a decrease over time as they may start to fail or break down, while others will then compensate and increase their activity to make sure the animal is still producing enough energy.” , he added.
In the Greenland sharks he examined, which were estimated to be between 60 and 200 years old, he found no significant changes in enzyme activity. Of course, a Greenland shark may only have an average age of 200 years, so the same may not be true when they reach their third or fourth century of life.
Camplisson plans to look at more enzymes to see if and how they change as sharks age.
Aging is complicated
There is still a lot of work to be done before this kind of research can be applied to humans.
“Aging is an incredibly complex system, and we still don’t have a definitive answer to exactly how it works,” Camclison said.
For example, changes in metabolism are only one part of aging in humans. Genetic errors, protein instability, and several other processes are among what are known as the “hallmarks of aging.” Camclison believes that sharks have a lot to teach us in these areas.
“We want to take a closer look at some of these hallmarks to determine if the Greenland shark is showing any signs of traditional aging,” he said.
Although the remarkable aging process of bowhead sharks has allowed them to survive for centuries, it can also be a double-edged sword as their environment changes rapidly.
The species, considered “near threatened” by the World Conservation Union, may be too slow to adapt to climate change, marine pollution and other stressors, Camclison said.
