Bone shard sheds light on ancient human interbreeding

A small piece of bone uncovered from a cave in Siberia came from a child whose mother was Neanderthal and whose father was a Denisovan, shedding new light on human ancestor relationships.

Researchers from the Max Planck Institute for Evolutionary Anthropology first came across the bone. After extracting DNA from the sample, they found it had chromosomes from a Neanderthal female and a Denisovan male.

That is the first example of that coupling on record.

“If you had asked me beforehand, I would have said we will never find this, it is like finding a needle in a haystack,” said study co-author Svante Pääbo, director of the Max Planck Institute for Evolutionary Anthropology, according to The Guardian. “And then we stumbled across it. I was very surprised.”

Roughly 40,000 years ago Eurasia hosted the Neanderthals in the west and Denisovans in the east. While the groups broke off from each other about 390,000 years ago, they did cross paths in certain regions from time to time.

One such area was the Denisova cave in the Altai mountains in southern Siberia. That is where the new bone fragment comes from, and it shows the two species did intermingle.

Analysis on the bone showed it belonged to a girl at least 13 years of age who lived 50,000 years ago. Though she inherited Neanderthal genes from her mother, she also got Denisovan DNA from her father.

Such information is significant because it shows that there are still many mysteries about ancient people that scientists do not yet know. The team next plans to analyze dust from the cave to see what else they can uncover about ancient populations.

“An interesting aspect of this genome is that it allows us to learn things about two populations – the Neandertals from the mother’s side, and the Denisovans from the father’s side,” explained Fabrizio Mafessoni, a researcher at Max Planck Institute for Evolutionary Anthropology, in a statement.

The research is published in the journal Nature.