WildTibet | 190,000 years ago, Denisovans were on the Qinghai-Tibet Plateau
< strong>”Nineteen thousand years ago, the Denisovans were on the Qinghai-Tibet Plateau”
“Who am I?””Where do I come from?” While philosophers are meditating metaphysically, scientists are busy searching for evidence in the real world.
The Denisovans are a newly discovered group of ancient humans, and Neanderthals who were once widely distributed in Europe are sister groups, and have genetic contributions to the indigenous populations of modern Oceania, East Asia, South Asia and America, and are a research hotspot of widespread international concern.
On October 30, at the”Archaeological China” major project important progress meeting held by the State Administration of Cultural Heritage, Zhang Dongju, a professor at the School of Resources and Environment of Lanzhou University, introduced the Baishiya Karst Cave Ruins Project in Xiahe, Gansu. The latest developments in the study of Denisovans.
“With the help of a variety of scientific and technological means, the project team established a reliable chronological framework for the site about 190,000 to 30,000 years ago, using emerging sediments DNA analysis technology successfully obtained a large amount of mitochondrial DNA of Denisovans, revealing that Denisovans were widely distributed on the eastern side of Eurasia during the Late Pleistocene and lived on the Qinghai-Tibet Plateau for a long time.” Zhang Dongju introduced the research in Beijing. It will be published online in the Science Journal on October 30th.
Time to occupy the Qinghai-Tibet Plateau As early as 190,000 years ago
The Qinghai-Tibet Plateau is known as the”Third Pole” and”Roof of the World”. Since when humans came to live in this alpine region has always been a mystery.
Previously, the team of Gao Xing, a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, went on the Qinghai-Tibet Plateau and discovered a Paleolithic site with native strata on the Qiangtang Plateau in northern Tibet— -Niadi (Nwya Devu).
The excavation and research of the Niadi site by Gao Xing et al. showed that humans tried to conquer the extreme high-altitude environment of the Qinghai-Tibet Plateau about 40,000 to 30,000 years ago.
“Our research on the Baishiya Karst cave site promote the earliest time of human occupation of the Qinghai-Tibet Plateau from 40,000 years ago to 190,000 years ago, and proves It was discovered that the Denisovans first occupied the Qinghai-Tibet Plateau. This is a major breakthrough in the study of the history of human activities on the Qinghai-Tibet Plateau.” Zhang Dongju pointed out.
The Baishiya cave site is located in Ganjia Township, Xiahe County, Gannan Tibetan Autonomous Prefecture, Gansu Province. An ancient human mandibular fossil was unearthed at the site in the early years. After physical anthropology, ancient protein and uranium dating techniques, it was confirmed as a Denisovan fossil about 160,000 years ago.
During excavations from 2018 to 2019, Lanzhou University, the Institute of Tibetan Plateau Research, Chinese Academy of Sciences, and the Institute of Vertebrate Paleontology and Paleoanthropology, etc. Four-dating and single-particle optical luminescence dating techniques have established a reliable chronological framework for the site about 190,000 to 30,000 years ago.
“In the site, according to the different sediment characteristics, we divided 10 strata, and collected a total of 10 strata from these strata 1310 stone products and 579 animal bone fragments. After carbon fourteen and optical luminescence dating of the collected samples, we found that ancient humans lived at the site for about 190,000 to 30,000 years ago.” The first author and corresponding author Zhang Dongju introduced.
The first extraction from sediments in China To ancient human DNA
Using sediment DNA analysis technology to successfully obtain a large amount of Denisovan mitochondrial DNA, yes A highlight of the archaeological research work at the Baishiya cave site. “This is also the first time that ancient human DNA has been successfully extracted from soil sediments in China, and it is also the first Denisovan DNA sequence obtained outside of Denisovan Cave in Siberia”, the last corresponding author of the paper, Chinese Academy of Sciences Introduction by Fu Qiaomei, researcher at the Institute of Vertebrate Paleontology and Paleoanthropology
Sediment DNA analysis is an emerging ancient DNA analysis technology, and the sediments on the archaeological site can be traced and related The DNA preservation status of the site and the possible existence of ancient humans have made up for the shortcomings of human fossils which are generally encountered but not desired. For the study of paleolithic archaeology The evolution of the population at the site opened a new window.
Before the excavation of the site, Zhang Dongju and Fu Qiaomei worked out a sampling plan for ancient DNA analysis of sediment samples to ensure that the samples were collected and transported without being contaminated by modern humans. In order to identify and isolate the target DNA from the DNA of massive environmental microorganisms, Fu Qiaomei’s team used efficient ancient DNA capture technology to fish out 242 mammalian and human mitochondrial DNA from 35 sediment samples. Enrich the DNA of ancient humans.
These ancient DNAs are like a key, opening the door to the world tens of thousands of years ago. Analysis shows that the Denisovan DNA found at the site mainly appeared in 100,000 years ago and 60,000 years ago, among which the Denisovan DNA about 60,000 years ago and Southern Siberia The late Denisovans of Denisovan Cave have the closest genetic connection. The DNA of Denisovans about 100,000 years ago separated from the late Denisovans earlier, revealing that Dan Nisovans were widely distributed on the east side of Eurasia during the late Pleistocene and lived on the Qinghai-Tibet Plateau for a long time.
The significance of clarifying the origin of modern people Significant
In the past 30 years, the issue of the origin of modern humans has become a hot focus in the academic circle, centering on”out of Africa” and”multi-regional evolution”.”The hypothesis forms a diametrically opposed academic camp between the two schools, and they are engaged in fierce academic debates.
“From Africa” believes that modern humans originated in Africa about 200 to 100,000 years ago; Africa is the only place of origin of modern humans, and modern humans in other regions originated from Africa The result of post-migration proliferation, and this proliferation is a complete replacement process.
The”multi-regional evolution theory” believes that the early Homo sapiens even the late Homo erectus Human beings are a biological population, and no new differentiation has occurred. The evolution of East Asia since Homo erectus has been continuous, there is no interruption in the evolution chain, and no large-scale immigration replacement events have occurred during this period.
“”From Africa” believes that during the coldest time of the last ice age, ancient humans all over the world were basically extinct, and only a small part of Africa where ancient humans survived and then spread to all parts of the world Research on the Baishiya cave site shows that there were Denisovans in the Qinghai-Tibet area around the last glacial period. Therefore, it is believed that the extinction of ancient humans in other regions except Africa during the last glacial period is worthy of reconsideration.” Wang Youping, a professor at the School of Archaeology, Arts and Sciences, Peking University pointed out .
In Wang Youping’s view, the discovery of the Denisovan in Baishiya cave filled the gap in the identification of specific species of ancient populations between Homo erectus and modern people in East Asia. The species identification of ancient human fossils during the same period provided key comparative materials, which are of great significance to clarify the evolutionary history of ancient humans in East Asia and the origin of modern humans. It is a major breakthrough in Paleolithic archaeology in recent years.
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