Wednesday , March 3 2021

Scientists have obtained the oldest DNA in the world. From the tusks of a mammoth that lived more than a million years ago



The researchers analyzed three tusks of permafrost mammoth in Siberia. They found that they were 1.2 million years ago, about 1.1 million years ago, and 700,000 years ago. And it is the oldest specimen that comes from a mammoth, which received the nickname Krestovka after the river of the same name in this area of ​​Russia, wrote National Geographic magazine.

According to paleontologists, the Krestovka mammoth was different from the other Siberian mammoths that inhabited our planet more than two million years ago. The researchers gained knowledge about the evolution and migration of mammoths by comparing them to the DNA of furry mammoths, the last living members of this species of octopus.

The last mammoths finally disappeared about 4,000 years ago, Reuters recalls.

Remains discovered in the 70s

In any case, the scientists announced Wednesday, Feb. 17, that they had obtained and sequenced DNA from the remains of three mammoths, the “cousins” of today’s elephants. Mammoths were one of the great mammals that dominated glacial-era landscapes. Their specimens remained buried in permafrost conditions, which led to the preservation of prehistoric genetic material.

But while these mammoth remains were discovered in Siberia in the early 1970s, new scientific methods were needed to extract the DNA. The oldest of the three, discovered near the Krestovka River, was about 1.2 million years old. Another, near the Adyč River, was between one and 1.2 million years old. The third mammoth of the Chukochya River lived about 700,000 years ago.

“The DNA in question is incredibly ancient. It is a thousand times older than the Vikings and still far precedes the existence of modern humans and Neanderthals,” said evolutionary geneticist Love Dalén of the Swedish Center for Paleogenetics. research now published in the journal Nature.

The first mammoths to leave for North America

The oldest of the three specimens, the Krestovka mammoth, belonged to a hitherto unknown genetic line that more than two million years ago separated from the line leading to the well-known furry mammoth, which humans knew well.

One of the authors of the new study, geneticist Tom van der Valk of the Swedish laboratory SciLifeLab, claimed that members of the “Krestovka line” were the first mammoths to migrate from Siberia to North America via a land bridge. already extinct about 1.5 million years ago. The hairy mammoth later migrated, about 400 to 500,000 years ago.

Illustration of a hairy mammoth (Mammuthus primigenius)

Photo: Profimedia.cz

Experts also revealed that the mammoth line “Adyč” was the ancestral ancestor of the furry mammoth, and that the individual “Čukočja” is once again one of the oldest remains of the furry mammoth.

The oldest DNA revealed to date, a self-replicating material that carried genetic information in living organisms, came from a horse that lived in the Canadian Yukon about 700,000 years ago. In comparison, the human species Homo sapiens first appeared about 300,000 years ago.

“This is the first time someone has obtained DNA from samples from more than a million years old, which has been a challenge. It took us several years to obtain the data and analyze it,” Dalén added. Reuters.

Most of the knowledge about prehistoric creatures comes from the study of fossils in their bones, however, this research reaches certain limits. Old DNA can help fill in the gaps, but it is perishable very quickly. New sophisticated research techniques allow experts to retrieve increasingly old genetic information.


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