A detail of the skeleton of an adult woman found at the “Sa” point of the Horinouchi Shell Mound archaeological site, late Jomon period.
The ancient Jomon of Japan may have avoided reproducing with this extinct human species.
Pleistocene humans didn’t hold back and Denisovans, which is why most of us now carry them extinct.
However, there is a group of prehistoric humans, who lived in what is currently Japan, who seem to have been excluded from all this inter-homid promiscuitygiving rise to an ancient community with strangely low levels of Denisovan ancestry.
Unlike Neanderthal DNA, which is uniformly distributed throughout modern non-African populations, Denisovan ancestry it’s something irregular.
The inhabitants of Oceania and island Southeast Asia inherited around 4% of their genomes from this ancient lineage, while other Eurasian and Native American communities have about 0.2% of Denisovan DNA.
This suggests that the crossing between A wise man e Denisovans may have occurred multiple times in different geographic regionsresulting in a complex distribution of introduced genes.
To better understand this process, the authors of a new study sought Denisovan DNA in 115 genomes of early modern humanswhich they then compared with 279 current individuals.
Surprisingly, they discovered that the Jomon, a group of hunter-gatherers who occupied Japan about 16,000 to 3,000 years agothey had a lot less Denisovan ancestry than all other East Asians.
The results of the , conducted by a team of researchers from the Max-Planck-Institute for Evolutionary Anthropology, in Germany, were published on Monday in the journal Current Biology.
This discovery becomes even more peculiar due to a series of recent discoveries that suggest the Denisovans were widely distributed throughout eastern Asia, highlights the .
However, although the Jomon have trace amounts of Denisovan DNA, their unusually low levels of genetic admixture suggest that they may have descended from a population that did not reproduce with our extinct sister lineage.
It’s unclear exactly how this group could have remained genetically isolated, although researchers propose two possible scenarios.
In the first of these scenarios, the Jomon may descend from a group that simply never got in touch with the Denisovans and later received very small amounts of Denisovan DNA by breeding with other modern humans who carried some of these archaic genes.
The second scenario, in turn, states that the ancestors of the Jomon were part of a initial crossover wave which resulted in only a tiny amount of Denisovan DNA being introduced into the modern human genome, but they were excluded from a subsequent round of contact which produced higher levels of gene flow.
And while it’s impossible to say which of these explanations is closer to the truth, the study authors maintain that their results support the existence of an ancient modern human lineage deep in East Asia with limited Denisovan ancestry—or none at all.
Thus, say the study authors, at least one Asian lineage Early Eastern Europe was not in contact, or was in limited contact, with the Denisovans.
