Neanderthals Mated with Denisovans, Exceeded Modern Human Diversity

Neanderthals and Denisovans were prehistoric humans who interbred to some extent also with members of the human lineage that led to modern humans. In this context, an international research team – Diyendo Massilani and colleagues – has now published the entire genome extracted from DNA isolated from a Neanderthal fossil that lived about 110,000 years ago. This is the first male genome determined from this species.

The Neanderthal man in question had died in Denisova Cave in the Altai Mountains, the same location where Denisovans also lived at times. According to the research group’s results, the man belonged to a human group that was more closely related to another Neanderthal found in the same cave, who had lived about 10,000 years earlier, than to his counterparts in Europe or to a Neanderthal from another cave in the Altai Mountains who lived about 80,000 years ago.

The genomes of both Neanderthals from Denisova Cave that have now been sequenced contained genes originating from Denisovans, indicating that the species interbred with each other at least in the Altai region more than 100,000 years ago. This was surprising, because later Neanderthals from the Altai region or from Western Europe show no evidence of such interbreeding.

Based on DNA – specifically the extent of homozygous chromosomal regions – it was also possible to conclude that Neanderthals living in the Altai region 120,000–80,000 years ago lived in smaller and more isolated groups than later European Neanderthals (54,000–40,000 years ago). In addition, the researchers observed that the genome sequences of Neanderthals belonging to these populations differed from each other more than the genomes of the most genetically distant modern human populations (the Mbuti of Central Africa and the Highland Papuans of New Guinea).

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The study I have briefly described above is unlikely to be directly applicable for commercial purposes. Instead, it satisfies our curiosity and fulfills our need for knowledge: the opening up of the ancient world is undeniably fascinating.

Perhaps even more important than curiosity and the desire for knowledge, however, is that as science advances, humanity’s awareness of itself and of the world increases. And over time, this influences the way we see ourselves and the world we live in.

It is, of course, true that this perspective does not affect all people in the world equally: there is a significant difference, for example, in how the Taliban in Afghanistan and secularized Europeans perceive the world. Whereas the former are guided by the writings of a prophet and war leader who lived in the 7th century, the latter make their everyday decisions based on modern scientific knowledge—though usually without explicitly realizing it.

The contribution of paleogenomics—the field represented by the study described above—may not be decisive in this broader picture, but it is not negligible either. Awareness of the lives of our ancient relatives in small, isolated populations, their interbreeding with each other—and with our ancestors—and the extinction of those lineages provides important context for understanding present-day humanity and its peoples.

Previous thoughts on the same topic:
The Surprising Story of Europe’s Hippos
The Historical Merging of Human Groups
American black population more vulnerable to the Omicron variant of SARS-CoV-2