The genome of a finger than 30,000 years old discovered in Siberia confirms the existence of a new relative of the human: "denisovanos." The international team of researchers conducted genetic analysis of the fossil found in Denisova Cave, in southern Siberia, says that it belonged to a girl who was not Neanderthal and modern human.
This, say the scientists in the journal Nature, a group of hitherto unknown human who lived in much of Asia during the Pleistocene epoch.
The small bone fragment of a little finger was found in 2008 during archaeological excavations in Denisova Cave in the Altai Mountains.
Details of the find, which initially was called "Madame X" were published last March in Nature.
But now, after sequencing the genome of the fossil and comparing it with the genomes of Neanderthals and modern humans, scientists conclude that it does not belong to either. Family
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The researchers have dubbed "denisovanos" in honor of the cave where it was discovered the fossil.
According to scientists, denisovanos hominins were a group close to the Neanderthals, who descended from the same ancestral population but subsequently split from the ancestors of modern humans.
Unlike the Neanderthals, the authors say, the denisovanos not share genes with the current Eurasian.
But they have a large number of similarities between genetic variants in modern populations of Papua New Guinea.
This suggests, say scientists who were a cross between denisovanos and the ancestors of the Melanesians.
It was thought that Neanderthals and humans were the only modern hominids that lived in Europe and Asia during the late Pelistoceno.
But now, the discovery of the denisovianos, which the scientists shared the same areas that humans and Neanderthals, shows that in regard to human evolution things are not so simple.
"The story is complicated now," said Professor Richard Green, University of California, Santa Cruz, who participated in the investigation.
"Instead of the clear history that we used to explain the migration from Africa of modern humans and the replacement of Neanderthals, we now have these lines crossed with more participants and more interactions than previously knew, "adds the scientist.
Investigators believe a group of ancestors probably went first Africa between 300,000 and 400,000 years and spread rapidly.
One branch became Neanderthals, that spread through Europe and the other branch migrated eastward and became the denisovanos.
When modern humans left Africa between 70,000 and 80,000 years, first encountered the Neanderthals and then contacted with denisovanos.
More characters?
Scientists do not know why until now the fossil evidence did not disclose the existence of this group of human relations.
But according to Professor Green, at first it was thought that the finger of Denisova pertencecía a modern human.
"Maybe other samples have been wrongly classified," says the scientist.
"But now, with DNA analysis techniques, we can say with more certainty of what they are."
Researchers believe that in the coming years there could be new discoveries that further complicate the theory of human evolution.
"This study clarifies some details, but we want to know much more about the denisovanos and its interaction with modern human populations, "says the researcher.
" And we must ask whether there are other people who have not yet been discovered. Will there be a fourth character in this story? ".
The research involved scientists from Germany, Spain, China, Russia, Canada and the United States. (BBC)
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