The ancient DNA of two 7700-year-old women from a mountainous cave in far east Russia suggests they were closely related to the people who live in this remote and frigid corner of Asia today. The new discovery also suggests that in this region, farming spread through gradual cultural changes, rather than by an influx of farming people.
“The main significance is this finding of continuity over about 7000 years,” says Mark Stoneking of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who wasn’t involved with the work. This contrasts with many archaeological sites in Russia, Europe, and the Americas where ancient humans are rarely directly related to living people nearby, thanks to wholesale migration and mixing since the invention of agriculture about 12,000 years ago.
The ancient women were discovered in Chertovy Vorota Cave, known as Devil’s Gate Cave in English. The site was of particular interest to population geneticist Andrea Manica of the University of Cambridge in the United Kingdom because the skeletons of five humans were found with pottery, harpoons, and the remnants of nets and mats woven from twisted blades of wild sedge grass—which some (but not all) researchers consider a rudimentary form of early agriculture.
DNA was extracted from the teeth, inner ear bones, and other skull bones from two of the skeletons from Devil’s Cave, and Hungarian graduate student Veronika Siska was able to sequence enough of the nuclear genome to compare it to hundreds of genomes of modern Europeans and Asians. The team found that the two Devil’s Gate Cave women were most closely related to the Ulchi, indigenous people who today live a few hundred kilometers north of the cave in the Amur Basin where they have long fished, hunted, and grown some of their food. The ancient women also were related to other people who speak the remaining and endangered 75 or so Tungusic languages spoken by dwindling numbers of ethnic people in eastern Siberia and China. They were also related to a lesser extent to modern Koreans and Japanese.
The women also looked like people in the Amur Basin today—they had genes that suggest they had brown eyes; straight, thick hair; skin color similar to the Asian people; and shovel-shaped incisors, similar to Asians. They also were lactose intolerant, which meant they could not digest the sugars in milk—and probably did not herd animals that could be milked.
The Ulchi and other Amur groups show no evidence of inheriting a significant amount of DNA from any other, later group of people, the team reports today in Science Advances. This suggests that they were part of one continuous population that evolved in the region for at least 7700 years. If so, farming was not introduced to this remote and frigid corner of Asia by a major influx of migrants, but adopted instead by local hunter-gatherers who progressively added food-producing practices to their original lifestyle, Manica says.
Several paleogeneticists agree that the study has shown remarkable continuity between the ancient cave women and the Ulchi. Researchers disagree, though, whether the research shows that farming spread by diffusion of ideas in this part of Asia rather than being introduced by a major wave of farmers, as in Europe. There, Anatolian farmers from the Near East swept into Europe with a package of artifacts including tools, seeds, and domesticated animals, and replaced or interbred with the local hunter-gatherers 12,000 to 8000 years ago. “The two Devil’s Gate Cave samples are hunter-gatherers and thus the results say little about the spread of the [fully developed] agricultural package,” says paleogeneticist David Reich of Harvard University.
Archaeologist Francesco d’Errico of the University of Bordeaux in France, however, thinks that both the archaeology and genetics in Europe and now, in Eastern Asia, demonstrate that agriculture spread in different ways in different places. It “is a complex process in which in some cases people moved with their ideas and technology; in other cases, only the technology moved,” says d’Errico, not an author of the study. The best way to test this, says Stoneking, would be to get ancient DNA from the earliest farmers in the region.