Scientists say DNA belonging to the ancient human ancestor Denisovans, found in a Tibetan cave, may be 45,000 years old.
Ancient Denisovan mitochondrial DNA was recovered from the sediment from the limestone cave Paishia Karst Cave on the northeastern edge of the Tibetan Plateau at 3,280 meters above sea level.
Models The Denisovans occupied a high cave about 100,000 to 60,000 years ago, and most recently may have been 45,000 years ago.
If the DNA were actually only 45,000 years old, this species would have lived with modern humans in Northeast Asia.
Baishia Karst Cave, Tibetan Buddhist Sanctuary and the tallest paleontrological site for researchers
The Denisovans, a group of extinct hominins that left the Neanderthals about 400,000 years ago, may have lived more widely in Northeast Central Asia than scientists previously thought.
Sediment samples were analyzed by an international team including Charles Perrault at Arizona State University.
“When we started developing this project about 10 years ago, none of us expected the Baishya Cave to be such a fertile site,” he said.
‘We rarely scratched the surface – three small excavation units have yielded hundreds of stone tools, fauna and ancient DNA. There is still a lot to do. ‘
‘Future work in the Pyshia Cave may give us a truly unique approach to Denisov’s behavior, and confirms the emerging image, which means that like the Neanderthals, the Denisovans are not just parts of the human family tree.
“They were part of a web of extinct populations that contributed to the current human genetic pool and shaped the ways in which we began to understand the evolution of our species.”
Researchers have identified ancient mitochondrial DNA from the Denisovans, dating to 45,000 years ago, by examining the sediment of the Pyshia Karst Cave, located on a high plateau in Tibet.
A mandible fossil (‘Xiao mandible’) from the same cave dated 160,000 was previously identified as Denisovan based on an amino acid state.
This new study of DNA suggests that there is no doubt that the Denisovans have occupied the cave.
Evidence of the most ancient hominins above sea level is unusual due to the severity of conditions at high altitudes.
The life of the plateau is harsh due to its thin air, and humans can develop the disease anywhere above 2,500 meters above sea level.
The existence of DNA suggests that the Denisovans, like modern Tibetans, may have made adaptations to greater heights.
Dates of sediments with mitochondrial DNA, along with the 160,000-year-old Xiahoe mantle, claim that the Denizovans have been on the plateau continuously for thousands of years.
Picture, the Xiahoe mantle remains. The Denisovan jaw bone was first discovered in 1980 by a local monk
It would have been a long time before genetic adaptations emerged in the Denisovans, which would have helped to sustain the ill effects of high altitude.
This is the first time that the discovery of Denisovan DNA has been recovered from outside the Denisova Cave in Siberia, Russia.
This Siberian cave was formerly the only site in the world where a few DNA-bearing Denisovan fossils have been found.
In 2010, a finger bone belonging to a previously unknown genus of hominin was discovered buried in the Denisova cave in the Russian Altai Mountains.
Evidence of this new species forced anthropologists to modify the pattern of human evolution outside of Africa.
Scientists thought that modern humans left Africa about 60,000 years ago, and that when Western Eurasia was colonized, the world would be empty of any other ancient Homin species.
But this assumption stems from the fact that the prehistoric period of Asia was less known compared to Africa and Europe.
Researchers suspect that Denisovans are widespread in Asia based on the widespread Denisovan gene signal among Asians today.
The new study has been published in the journal Science.
The shared ancestors of the Denisovans and Neanderthals, unknown in the fossil record, are thought to have separated from the ancestors of modern humans about 800,000 years ago.
Who are the Denisovans?
The Denisovans are an extinct human species that seems to have lived in Siberia and even Southeast Asia.
Although the remains of these mysterious early humans were found only at one site in the Denisova cave in the Altai Mountains of Siberia, DNA analysis shows that they were widespread.
DNA from these early humans has been found in the genes of modern humans over a wide area of Asia, claiming to cover a wide range at one time.
DNA analysis of a portion of the pink finger bone in 2010 revealed that the Denisovans were related to Neanderthals but belonged to a different species.
They are considered to be the sister species of Neanderthals who lived simultaneously in West Asia and Europe.
Both species appear to have separated from a common ancestor about 200,000 years ago, while they separated from the modern human Homo sapiens lineage about 600,000 years ago.
The bone and ivory beads found in the Denisova cave were found in the same sedimentary layers as the Denisova fossils, which led to suggestions that they contained sophisticated tools and jewelry.
In 2010 DNA analysis of a portion of the fifth digit finger bone, which belonged to a young woman, revealed that they were related to Neanderthals but were different.
Later genetic studies suggested that the ancient human species separated from the Neanderthals 470,000 to 190,000 years ago.
Anthropologists are puzzled as to whether the cave was a temporary refuge for a group of these Denisovans or whether it created a more permanent settlement.
DNA from molar teeth belonging to two other individuals, an adult male and a young female, showed they died in a cave at least 65,000 years ago.
Other tests have suggested that the young woman’s tooth may be 170,000 years old.
The third molar pink discovery is thought to have belonged to an adult male who died 7,500 years ago.