Science has long known that people living in what is now Siberia walked (and later rowed) Crossing the Bering Strait into North America. But now new evidence suggests that these early migrations were not one-way trips: Published Thursday in current biologyResearchers say they have found traces of Native American ancestry in the DNA of Siberians who lived centuries ago.
This American heritage—which is still present today in the genomes of some Siberians—adds to the fragmentation of archaeological evidence that North Americans were in contact with their North Asian neighbors thousands of years before the arrival of Europeans.
This finding was not entirely unexpected. “Human movement is rarely one-way,” said University archaeologist Cosimo Posth, a co-author of the new study. Tubingen, Germany. “There’s usually a bit of back and forth.”
exact time and how people first got to america is one of the long-running debates in archaeology.Assumption dates vary widely, but many researchers agree that Earliest settlers may have crossed Bering land bridge, the narrow strip that periodically connected northern Asia to modern-day Alaska in prehistoric times.this Transcontinental highway succumbs to sea level rise Somewhere between 11,000 and 10,000 years ago, but that didn’t stop migrations between lands. Genetic studies and archaeological digs have shown that Siberians migrated to North America multiple times, including as recently as 1,000 years ago.
But while much research has focused on reconstructing the conditions under which people arrived in what is now Alaska, “very little is known about migration in the other direction,” Post said.
This situation is slowly starting to change. A 2019 study found that Genetic evidence of ancient people who lived on both sides of the Bering Strait connected to each other.A handful of archaeological finds in Alaska — including Discover 15th century glass beads This may have originated in Venice – pointing to ongoing trade between North America and the rest of the world.
But how far these relationships extend across the Strait is unclear. Little is even known about how people moved within Siberia over the past few thousand years. To reconstruct this part of the region’s history, Posth and his colleagues sequenced the DNA of 10 ancient people whose remains had been unearthed at various sites across Siberia.
The oldest of these samples date back 7,500 years. The study also included the genomes of three people who lived 500 years ago on the Kamchatka peninsula — which stretches from the Russian Far East to the southwestern Bering Strait. The sequences are the first samples of ancient DNA to come out of the remote peninsula, Posth said.
Siberia was once a hotbed of migration, bringing ancient Siberians into contact with populations as far away as Japan and Greenland, researchers have found. Their analysis also revealed previously unknown connections between Native Americans and the people who lived in Kamchatka centuries ago. The team found that these Kamchatka ancestors had met North Americans at least twice before: once between 5,500 and 4,400 years ago, and again about 1,500 years ago. These links suggest that Native American influence was deeper inland than previous studies.
Posth said he was hoping to find some evidence of Native American contact in Siberia, but he was surprised by how long ago those conflicts occurred. Those ancient encounters weren’t the last time Kamchatkas interacted with North Americans, either. The team found a higher proportion of Native American DNA in the genomes of modern Kamchatkas, suggesting that the peninsula’s people also had contact with North Americans over the past few centuries.
It’s unclear how the DNA from North America got into Kamchatka, Posth said. Kamchatka ancestors may have inherited DNA from other Siberians who carried this heritage, or they may have had contact with Native Americans themselves. Still, Posth and his colleagues’ research builds on previous genetic studies showing that DNA is migrating from North America to Siberia, said Dennis O’Rourke, anthropological geneticist at the University of Kansas, who was not involved in the new paper.
The fact that North Asians and North Americans did come into contact isn’t surprising, says Anne Stone, an anthropological geneticist at Arizona State University, given how close the two continents are to each other. new research. On the one hand, the Aleutian Islands (where the Aleutians historically hunted and traded) form a chain that runs from southwestern Alaska all the way west to Kamchatka.
As for the Bering Strait, Stone said that while the early inhabitants of the area may have become isolated from each other after the Bering land bridge disappeared, future generations would not be so confined. “They have boats,” Stone said. “So they can access and transact with each other.”