DNA of the denisovans can be found in the genomes of modern people of Asia, Australia and Melanesia.
The first inhabitants of Tibet were not the ancestors of modern Chinese, Nepalese or current residents of the plateau, and the ancient humans-the denisovans, who lived there more than 160 thousand years. Write about the geneticists and paleontologists, published an article in the journal Nature.
“The DNA of denisovans can be found in the genomes of modern people of Asia, Australia and Melanesia, indicating that their extremely widespread. However, to date, their bones were found only in the Russian Denisova cave,” says Jean-Jacques Hublin (Jean-Jacques Hublin) of the Institute of evolutionary anthropology in Leipzig (Germany).
In December 2010 the famous paleogenetic Svante Paabo announced the opening of the “third” kind of people whose remains one knuckle of a finger was found in the Russian Denisova cave in the Altai. This discovery was made thanks to the “resurrection” of fragments of the genome preserved in three fragments of bone of an ancient man – phalangeal finger bone and two teeth found in the cave.
Initially, scientists believed they found the “denisovans” (Homo altaiensis) was a cousin of the Neanderthals, who lived in a cave for about 50 thousand years ago. It was later revealed that they arose much earlier than scientists expected, and was a separate subspecies of humans. Traces of their DNA remains in the genomes of modern Polynesians, Indians of South America and several Nations of Southeast Asia.
Hublin and his colleagues opened the first “real” traces of the denisovans outside of Altai, studying the fragments of the jaw of ancient man which were found in 1980 by a Tibetan monk in the cave Baisha, located in the South of the County Xiahe in the Gansu province of China.
Long these remains have lain in the Treasury of one of the local incarnations of the Buddha. At the turn of the century he gave them to the scientists from Lanzhou University. They were interested in this discovery and organized a series of expeditions to the cave Baishya in the hope of discovering more remains of its owner, presumably a Neanderthal.
Three years ago, these excavations had joined the European geneticists, anthropologists and chemists. Scientists have not been able to find new bones of ancient people, but they found there a large number of tools, cut up animal bones and other artifacts. Their age was approximately 165 thousand years, spoke in favor of the very ancient origin of their owners.
The bones of an ancient “Neanderthal”, unfortunately genetics is not preserved important fragments of DNA that did not allow Oblio and his colleagues to reconstruct the genome of the occupant of Bisli. On the other hand, chemists have discovered in the teeth of this ancient people, a large number of proteins and other organic molecules, to reveal its origin.
It turned out that his teeth contained a unique set of proteins on a similar mix of Neanderthals nor CRO-magnon, nor modern apes. Part of these molecules, as noted by scholars, was similar in structure to the enzymes of the denisovans. This suggests that the cave dwellers or were pure Denisova, or a descendant of any mixed marriages between Homo neanderthalensis and Homo altaensis.
This discovery was a great gift for Oblina and his colleagues, as in the past, scientists managed to find only the teeth of Homo altaiensis and had no idea what they looked like. Now anthropologists can say that the denisovans differed in appearance from modern humans and from Neanderthals, and was similar in shape of jaws erectus people Homo erectus.
In addition, this discovery reveals the secret of how modern Tibetans have become owners of unusual and unique to them version of the EPAS1 gene that protects them from chronic lack of oxygen. Initially, biologists believed that it just quickly evolved, however, in 2014, they found that the Tibetans were “borrowed” it from the denisovans, with whom they interbred approximately 40-50 thousand years ago.
Such a hypothesis did not provide an answer as to where it happened this exchange. The discovery of the remains of denisovans to Tibet says that it “natives” and newcomers CRO-magnons could be a long time to live next to each other and in constant contact with each other, while the denisovans did not “blend” in a new population or disappeared, leaving them the gift of “mountain” version of EPAS1, the scientists conclude.
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