It is the only vertebrate that lives more than 500 years. And yet it lives 20 times less than any other animal

Sharks are often called living fossils. And that’s not strange. Plants first appeared on Earth about 470 million years ago, trees came about 390 million years ago. Sharks, on the other hand, emerged 450 million years ago, which means Before there were trees on our planet there were sharksas Emma Barnard of the Natural History Museum in London explains. It’s not surprising that they had so much time to evolve to become the longest-living vertebrates. But There’s one species in particular that stands out,

Scientists had long suspected that Greenland sharks were very long-lived, but there was no way to determine just how long they lived. Other shark species may have longer lifespans Estimate by counting the growth bands on the fin spines or their vertebraesomething like the rings of a tree. However, Greenland sharks have no fin spines or hard body tissue. Their vertebrae are too soft to form the growth bands seen in other sharks. Scientists could only assume that the sharks lived a long time based on what they knew: sharks They grow very slowly (less than 1 cm per year) And their size can be more than 6 meters. Thus, the figures indicate about 600 years.

But according to a study published in Science, recent advances have allowed scientists to use carbon dating to estimate the age of Greenland sharks. Inside sharks’ eyes are proteins that form before birth and do not degrade with age, like fossils preserved in amber. The authors, led by Julius Nielsen, found they could determine the sharks’ ages by carbon dating these proteins. The largest shark they analyzed, According to their estimates, a 5 meter woman will reach 512 years. The problem is that carbon dating can only provide estimates, not exact ages, but even if the estimates are based on the most limited data (just under 300 years), this animal would still be the oldest vertebrate on the planet.

One theory to explain this long life is that Greenland sharks have a very slow metabolism, adapted to living in cold, deep waters. A NOAA (National Oceanic and Atmospheric Administration) remotely operated vehicle diving off New England found With Greenland sharks at a depth of 783 metersbut it is known that these are sharks They dive to a depth of up to 2200 meters. It is the only shark that can withstand the cold waters of the Arctic Ocean all year round.

A slow metabolism may explain sharks’ slow growth, slow aging, and slow movements: Its maximum speed is less than 2.9 km/h. Because the sharks grow so slowly, they are not thought to reach sexual maturity until they are more than a century old. This means that removing mature Greenland sharks from the ocean impacts the species and the ecosystem for many decades.

Thus, the sharks analyzed to date must have been born at some point Between the years 1504 and 1755According to science, that would make him an example of someone who lived before Isaac Newton and who lived even before that They may have accompanied Columbus on his last voyages. Despite this, it is not the longest living animal.

That honor belongs to the hexactinellids, popularly known as glassy sponges. Although these organisms live a long time, it is difficult to calculate their exact age. one discovery published in Current Biology and based on the models, the estimated age of a specimen can be given. Scolymastra joubini In 23,000 years, with variations that can range from 13,000 to 40,000 years. Currently, glass sponges live in the East China Sea and the Southern Ocean They are over 10,000 years old.which makes them the longest-living animal on the planet.

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