A new study has concluded that Denisovans may have lived on the Tibetan Plateau tens of thousands of years before modern humans, leaving behind Denisovan DNA that helped Tibetans to adapt remarkably well to life at high altitudes.
After discovering Denisovan DNA in the genomes of residents now living in Tibet, scientists have suggested that these human ancestors of ours were happily living in Tibet 40,000 years before modern humans arrived on the scene.
According to the Daily Mail, scientists now believe that Denisovans were living on the Tibetan Plateau tens of thousands of years before they were first thought to arrive in this area. It has also been suggested that it may actually be through the help of Denisovan DNA that modern residents of Tibet have been able to adapt so well to life at perilously high altitudes, with the plateau of Tibet 12,000 feet above sea level.
Research conducted in the past originally tried to demonstrate that there were no humans in Tibet until around 3,600 years ago, but now new work conducted at the site of Nwya Devu disputes this, as Dr. John Olsen from the University of Arizona at Tucson recently explained.
“What we know is that the Denisovans left their homeland in the Altai Mountains of southern Siberia and eventually trekked all the way to Melanesia [the islands northeast of Australia], taking with them their signature genome. One logical route for such a migration may have included passage up and over the Tibetan Plateau.”
The archaeological site of Nwya Devu has been a hot spot for scientists for quite some time and stone tools that have been excavated here have been found to date back between 30,000 and 40,000 years. And there is also the crucial finding in Tibetan DNA which reveals that modern Tibetans may be the product of interbreeding which occurred between Homo sapiens and Denisovans. In fact, it is this small segment of DNA which scientists believe allows Tibetans today to survive with so little oxygen.
Because humans today contain traces of Neanderthal and Denisovan DNA, scientists like Dr. Adam Rutherford have written that we are all part of their very long genetic heritage, which begs the question of whether these two hominids were actually a different species after all. If this were the case, it would only make sense that the offspring of these separate species would be sterile, yet this is clearly not the case.
“Neanderthal DNA is slowly being purged from our genomes for reasons that are not fully understood, humans today bear their living genetic heritage, as we do the genes of another type of human, the Denisovans, further to the east.”
The new study which reveals that Denisovans may have lived in Tibet 40,000 years before modern humans has been published in Science.
Source: Read Full Article