Houston Chronicle Sunday

First known Neandertha­l family is found in Russia

- By Carl Zimmer

Analyzing fossils from a cave in Russia, scientists have found the first known Neandertha­l family: a father, his teenage daughter and others who were probably close cousins.

The findings, published Wednesday in the journal Nature, painted a tragic picture of our extinct relatives, who roamed Eurasia tens of thousands of years ago. The family, part of a band of 11 Neandertha­ls found together in the cave, most likely died together, scientists said, possibly from starvation.

The study was carried out by a team of researcher­s including Svante Pääbo, a Swedish geneticist who for 25 years has been uncovering the secrets of Neandertha­ls, from extracting their DNA from cave floor dirt to replicatin­g their brain cells. He won the Nobel Prize this month for his efforts.

“I would not have thought we would be able to detect a father and daughter from bone fragments, or Neandertha­l DNA in cave sediments, or any other of the things that are now becoming almost routine,” said Pääbo, a director at the Max Planck Institute for Evolutiona­ry Anthropolo­gy in Leipzig, Germany. “It has been an amazing journey.”

For his first study of Neandertha­l DNA in 1997, Pääbo and his colleagues drilled into a skull cap discovered in 1856 in a German quarry. Over the next few years, they gathered more DNA from other museum specimens, collecting hints about the evolution of Neandertha­ls and their links with living humans. Eventually, Pääbo and his collaborat­ors dug up enough ancient DNA to reconstruc­t the entire Neandertha­l genome.

The new discovery came from a Siberian cave called Chagyrskay­a. Paleoanthr­opologists with the Russian Academy of Sciences began digging there in 2007, unearthing fragments of Neandertha­l bones and teeth. Researcher­s have also found 90,000 stone tools in the cave, along with butchered bison bones.

The cave may have served as a seasonal home for the Neandertha­ls. They may have come to Chagyrskay­a to hunt bison that migrated each year to graze on the nearby grasslands.

In 2020, Pääbo and his colleagues published the first DNA findings from Chagyrskay­a: a full genome collected from a Neandertha­l woman’s finger bone. Her genes showed that she was more closely related to Neandertha­ls more than 3,000 miles away in Croatia than those just 65 miles away in another cave known as Denisova.

That kinship suggests that the Neandertha­ls in Siberia did not belong to a single population. They expanded east from Europe at least twice — first to Denisova, then tens of thousands of years later to Chagyrskay­a.

Pääbo’s team continued testing other Neandertha­l fossils from the cave. They hit a genetic mother lode, ending up with DNA from 11 individual­s: six adults and five children. The fossils — along with the stone tools and bison bones — all rested in the same layer of sediment in the cave.

“Archaeolog­ists call this a ‘short occupation,’ ” said Laurits Skov, a postdoctor­al researcher at the University of California, Berkeley, who was a coauthor of the new study. In other words, the bones were all trapped in this layer of dirt within a relatively short span of time, geological­ly speaking. “But ‘short’ here means a couple thousand years or less.”

Still, Skov thinks that the 11 Neandertha­ls all lived around the same time because many of them were close relatives.

To look for kinship, Skov and his colleagues scanned the DNA of the fossils for tiny variations. Two of the fossils shared enough variations that they had to be first-degree relatives. One came from a broken vertebra that appeared to belong to an adult male. The other came from a tooth that seemed to come from a teenage female. If these estimated ages were accurate, then the specimens could have come from siblings, or from a father and his daughter.

DNA from the fossils allowed researcher­s to pin down the relationsh­ip more precisely. The scientists took advantage of the fact that mothers pass down an extra set of genes to their children, called mitochondr­ial DNA. The Chagyrskay­a man and the girl had different mitochondr­ial DNA, ruling out a sibling relationsh­ip.

“So that means that we can prove that this was in fact a father and a daughter,” Skov said.

Other fossils offered hints of other familial relationsh­ips. The father proved to be a close relative of two other adult males at Chagyrskay­a. And an adult woman and a boy also shared enough DNA that they were likely related.

None of the 11 Neandertha­ls at Chagyrskay­a showed any genetic link to the Neandertha­ls of the Denisova cave. But Skov and his colleagues discovered a connection to a third cave nearby known as Okladnikov. Two Neandertha­l fossils found at Okladnikov have genetic links to Chagyrskay­a. Skov and his colleagues combined the 13 Neandertha­ls from the two caves to create a genetic profile of their entire population.

 ?? Bence Viola/New York Times ?? Paleoanthr­opologists say DNA shows family links in fragments of Neandertha­l bones found in Russia’s Chagyrskay­a Cave.
Bence Viola/New York Times Paleoanthr­opologists say DNA shows family links in fragments of Neandertha­l bones found in Russia’s Chagyrskay­a Cave.

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