Ancient DNA Links Humans Living 40,000 Years Ago to Many Asians & Native Americans
An international team of researchers sequenced nuclear and mitochondrial DNA that had been extracted from the leg of an early modern human found in Tanyuan Cave near Beijing, China. Analyses of the DNA showed that the Tianyuan human shared a common origin with the ancestors of many present-day Asians and Native Americans.
Researchers, who included Svante Pääbo and Qiaomei Fu of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, also found that the proportion of Neanderthal and Denisovan DNA is not higher than people who live in the region currently.
Humans with morphology that is similar to present-day humans appear in the fossil record across Eurasia between 40,000 and 50,000 years ago. Genetic relationships between the early modern humans and present-day human populations hadn't been established.
Researchers extract the nuclear and mitochondrial DNA from a 40,000 year old leg bone that was found in 2003 at the Tianyuan Cave site. Researchers used new techniques that can identify ancient genetic material from an archeological find even when large quantities of DNA from soil bacteria are present.
Next, the researchers reconstructed a genetic profile of the leg's owner. Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology, who led the study, said:
"This individual lived during an important evolutionary transition when early modern humans, who shared certain features with earlier forms such as Neanderthals, were replacing Neanderthals and Denisovans, who later became extinct."
This early human's genetic profile revealed that it was related to the ancestors of many present-day Asians and Native Americans, but had already diverged genetically from the ancestors of present-day Europeans.
The scientists also found that the Tianyuan human did not carry a larger proportion of Neaderthal or Denisovan DNA than present day people in the region. Pääbo added"
"More analyses of additional early modern humans across Eurasia will further refine our understanding of when and how modern humans spread across Europe and Asia."