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Tianyuan Man Genome Reveals The Nuances of Asian Prehistory

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A new study in Current Biology analyzed the entire genome of the Tianyuan man who was found near Beijing, China and lived around 40,000 years ago. The Tianyuan man’s genome marks the earliest ancient DNA from East Asia, but this is not the first time we have studied Tianyuan’s genes.

The Tianyuan skeleton was unearthed near the Zhoukoudian site, about 50 km southwest of Beijing.

The Tianyuan skeleton was unearthed near the Zhoukoudian site, about 50 km southwest of Beijing.

In 2013 paper in PNAS, the same group that published the Current Biology paper showed there is a closer relationship of Tianyuan to present-day Asians, based off his genes, than to present-day Europeans. At that time it was suggested that present-day Asian history has a deep lineage as far back as 40,000 years ago.

In the last 4 years, we have had more data showing that modern Europeans derive from more prehistoric populations which separated early from other early non-African populations soon after the migration out of Africa. This hasn’t changed our understanding of East Asian ancestry however, showing that Tianyuan’s genetic similarity to Asians remained in comparisons including ancient Europeans without mixed ancestry…

But, most interestingly it was surprising that when they compared Tianyuan to the 35,000-year-old individual from Belgium, GoyetQ116-1, who in other ways reflected an ancient European, he shared some genetic similarity to the Tianyuan individual that no other ancient Europeans shared. This suggests that the two populations represented by the Tianyuan and GoyetQ116-1 individuals derived some of their ancestry from a sub-population prior to the European-Asian separation. The genetic relationship observed between these two ancient individuals is direct evidence that European and Asian populations have a complex history.

Another unexpected result sheds light on the Peopling of the America’s theory. In 2015, a study comparing present-day populations in Asia to those in the Pacific and the Americas, showed that some Native American populations from South America had an unusual connection to some populations south of mainland Asia, most notably the Melanesian Papuan and the Andamanese Onge. They proposed that they could not have come from a single unit, but rather more than one group crossed and had additional ties to an Asian population that also contributed to the present-day Papuan and Onge.

f3(Tianyuan, X; Mbuti) for All Sites Where X Is a Present-Day Human Population or an Ancient Individual  The f3 statistic ranges from 0.04 to 0.25. A higher value (red) indicates higher shared genetic drift between the Tianyuan individual and the (A) present-day population or (B) ancient individual. The intersection of the dotted lines indicates where the Tianyuan Cave is located. See also Table S2A.

f3(Tianyuan, X; Mbuti) for All Sites Where X Is a Present-Day Human Population or an Ancient Individual The f3 statistic ranges from 0.04 to 0.25. A higher value (red) indicates higher shared genetic drift between the Tianyuan individual and the (A) present-day population or (B) ancient individual. The intersection of the dotted lines indicates where the Tianyuan Cave is located. See also Table S2A.

There are no trace of this connection in present-day East Asians and Siberians, but the Tianyuan man possesses genetic similarities to the same South Americans, in a pattern similar to that found for the Pacific groups. So this new study confirms that the multiple ancestries represented in Native Americans were all from populations in mainland Asia… What is intriguing, however, is that the migration to the Americas occurred approximately 20,000 years ago, but the Tianyuan individual is twice that age. Thus, the population diversity represented in the Americas must have persisted in mainland Asia in two or more distinct populations since 40,000 years ago.

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