The crossing of modern humans and Neanderthals 35,000 years ahead – Parole

Sync Agency | 12:58 // 18 February 2016

The ancestors of Neanderthals in the Siberian Altai Mountains, located near the border between Russia and Mongolia, and modern humans were able to match and mate much sooner than was estimated in these groups, according to a study published in the journal Nature.

“We have the first genetic evidence that modern humans have migrated and Africa 100,000 years ago. It also tells us that modern humans and Neanderthals interbred multiple times over many thousands of years, “ Sync declares Sergi Castilian, researcher at the Max Planck Institute (Germany) and co-director of the work.

“This is the first genetic evidence that modern humans have migrated from Africa and 100,000 years ago,” Sync declares Sergi Castilian

the results They imply that some modern humans left Africa early and were mixed with Neanderthals. These individuals later become extinct and, therefore, are not ancestors of those who left Africa about 65,000 years ago, around the time that modern human populations spread across Eurasia.

According to the scientific, modern humans that are genetically mixed with the Neanderthal individual must have come from a population that left Africa before the migration of the ancestors of today’s European and Asian ancestry.

so probably there was a long delay between the time when this group branched into the pedigree of modern humans-about 200,000 years ago and when they left their genetic mark on the Neanderthal about 100,000 years ago-Altai .

the team analyzed the genomes of a Neanderthal and Denisova hominid (which remains of a finger and a tooth is lost) in the Altai mountains, and two human genomes today. Altai Neanderthals are the only representative of this group in Asia known scientists. “It was a very small population,” adds the researcher

They also studied data from the sequence of chromosome 21 two Neanderthals. One from Spain and one from Croatia. “Spanish is Sidrón cave in Asturias, since we have a bone with little contamination from modern DNA,” explains Castilian.

Neanderthals separated from their European cousins ​​

genetic evidence shows that a number of modern humans out of Africa together with the ancestors of Neanderthals Altai about 100,000 years ago. However, they did not detect any genetic contribution in the Denisova hominid or European Neanderthals.

Genetic testing a number of modern humans out of Africa together with the ancestors of Neanderthals Altai

“this suggests that Neanderthals occurred while Europe migrated eastward. Quite possibly Denisovans find other populations of modern humans in Asia, since Asians have Denisovan DNA, “ says scientist at the Max Planck Institute.

That does not mean that modern humans never mate with Denisovans or European Neanderthals. Adam Siepel, co-author and president of the Center for Quantitative Biology CSHL Simons (USA) said:

“The signal we’re seeing in the Neanderthal Altai probably comes from an event of interbreeding occurred after this Neanderthal lineage split from their European cousins, some 100,000 years ago. “

so, modern human DNA sequences in Neanderthal Altai seem to derive from a modern human group that broke away early form of others.

Martin Kuhlwilm, who participated in the study and is currently a researcher at the Institute of Biology evolutionary (CSIC – UPF), which is also co-author of the study, identified the regions of the Neanderthal that comes from Altia modern human genome. I was looking for sequences in the genome of Siberian Neanderthal were similar to sequences of the human genome.

We know that contemporary human DNA contains no remains of Neanderthals Africans, so it was not useful to us. Therefore contemporary use genomes African individuals to identify mutations that most had in common. Some of these mutations also appeared in regions of the Neanderthal Altai, crossing a test genome, “he says.

” This discovery represents another step in the demolition of the old paradigm of human evolution. Now we know that there have been multiple crosses between modern humans and archaic hominids that have helped to accelerate the adaptation of these populations, “says Carles Lalueza-Fox, head of the Laboratory of Paleogenomics the Institute of Evolutionary Biology, further believes that this must have happened also in the remote past of our lineage, millions of years ago.

the authors speculate that the modern human population could have interbred with Neanderthals in southwest Asia, where it is believed that both were present 120,000 years ago. Alternatively, in southern Arabia and the area around the Persian Gulf, which also could have been settled early.