There are also Greenland sharks that are older than the United States.
The lifespan of these deep-sea sharks is estimated to be at least 270 years. Some have even lived for over 500 years. Biologists have identified a key reason for this shark’s incredible longevity: Arctic sharks, which live thousands of feet deep in the ocean, don’t age like other animals. As they get older, their metabolism slows down and cellular changes occur. However, when researchers analyzed Greenland sharks of different ages, they found that their metabolism doesn’t slow down. This shark is biologically fascinating.
“Every detail about this animal is fascinating, and the more we learn, the more motivated we are to continue researching it,” Euan Camplison, a PhD candidate biologist at the University of Manchester, told Mashable.
A dominant shark lurks in the deep, dark ocean. Meet the river thrush.
Camplison presented the new research at the Society for Experimental Biology’s annual meeting in July.
Sharks don’t just live a long time; they’re also the only shark species that can survive all year in the frigid Arctic. And that’s not all: “considering their body size, they are one of the slowest swimmers of any fish, females only become sexually reproductive at about 150 years of age, they have small brains that seem to enable them to hunt and travel long distances, a large portion of the population spends most of their lives with eye parasites, and their flesh is full of toxins such as TMAO and urea that make it toxic for humans to eat,” marveled Camplisson.
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Scientists suspect that the shark’s extremely slow movements and cold climate may contribute to the species’ unusual longevity, and these are likely important factors. But Camplisson has noticed that other Arctic fish species, such as the Arctic wolffish, also live in cold waters, are predatory, and are relatively sedentary; however, this fish only lives for around 20 years. Another deep-sea species, the dominant filefish, is predatory, slow-moving, and lives in cold, deep waters (it is found in oceans around the world), but it can live for as long as 80 years. Centuries.
“So we thought there must be other factors at play in this shark’s lifespan,” Camplison said.
A Greenland shark was discovered more than 2,500 feet below the surface off the northeastern coast of the United States.
Credit: NOAA Office of Ocean Exploration and Research
A graph showing how researchers measured metabolic activity in Greenland shark tissues.
Credit: Ewan Camprisson
So Camplison and his team looked at shark metabolism. They used preserved red muscle from 23 Greenland sharks of different ages to see how their metabolic enzymes responded when they were activated. The sharks ranged in age from about 60 to 200 years old. As seen above, the muscle samples were suspended in a liquid that reacted to changes in the enzymes: the more active they were, the greater the color change. They measured these changes with a machine called a spectrophotometer, which evaluates changes in the intensity of light. And as mentioned before, the sharks of all ages showed no signs of metabolic slowdown.
It’s clear that these Arctic sharks are long-lived, but the reasons for this are unclear: perhaps gradual growth and maturation over a century or more simply prepares them for success as adults.
“My guess is that the deep Arctic ocean may be a harsh environment to live in, where animals like pythons may not have constant access to enough food and may not come into frequent contact with other pythons,” Camplison explained, noting that pythons swim slowly in a vast ocean environment. And, importantly, pythons have few predators. There is little to stop them from thriving in the deep sea. “So, as a species with low natural mortality, their optimal life strategy is to grow slowly and store energy so that when they come into contact with the opposite sex, they are in good condition to reproduce,” he said.
Scientists take tissue samples from a Greenland shark.
Credit: Ewan Camprisson
With these fascinating findings, Camplison plans to further analyze these sharks’ tissues and anti-aging metabolism, and not just to satisfy his curiosity about deep-sea biology.
“If we can understand why Greenland sharks live so long and why they are so resistant to age-related diseases (such as heart disease), I think we may be able to improve the quality of life for older people,” he said.
