by ERIC RALLS
A groundbreaking new study suggests that the migration of ancient humans to the Americas occurred 26,000 years ago, a full 10,000 years earlier than previously believed.
The research, carried out by scientists from the Chinese Academy of Sciences, provides evidence that the first migrants originated from the northern coastal region of China, debunking the longstanding theory that ancient Siberians who crossed the Bering Strait land bridge were the sole ancestors of Native Americans.
The team of researchers, led by molecular anthropologist Dr. Yu-Chun Li, traced a female lineage by analyzing mitochondrial DNA, which is inherited from mother to offspring. They discovered links between East Asian Paleolithic-age populations and founding populations in Chile, Peru, Bolivia, Brazil, Ecuador, Mexico, and California.
Multiple migration events discovered
The study also unveiled another migration event that took place 19,500 years ago, which saw a rapid population increase due to an improved climate.
“The Asian ancestry of Native Americans is more complicated than previously indicated,” explained Dr. Li. “In addition to previously described ancestral sources in Siberia, Australo-Melanesia, and Southeast Asia, we show that northern coastal China also contributed to the gene pool of Native Americans.”
The research focused on the D4h lineage, which allowed the team to trace maternal ancestry over a decade.
How the study was done
The scientists analyzed 100,000 modern and 15,000 ancient DNA samples from across Eurasia, eventually identifying 216 contemporary and 39 ancient individuals from the D4h lineage.
By examining mutations that had accumulated over time, considering the samples’ geographic locations, and employing carbon dating techniques, the researchers reconstructed the origins and expansion history of the D4h lineage.
This discovery sheds light on the archaeological similarities between the Paleolithic peoples of China, Japan, and the Americas.
“This suggests that the Pleistocene connection among the Americas, China, and Japan was not confined to culture but also to genetics,” said study senior author Qing-Peng Kong, an evolutionary geneticist at the Chinese Academy of Sciences.
What the researchers learned
The results revealed two distinct migration events. The first took place between 19,500 and 26,000 years ago during the Last Glacial Maximum, when ice sheet coverage was at its peak and climate conditions in northern China were likely unfavorable.
The second migration occurred during the melting period, between 19,000 and 11,500 years ago, with increasing human populations possibly triggering these migrations.
Interestingly, the study found a surprising genetic link between Native Americans and Japanese people, particularly the indigenous Ainu.
During the melting period, a subgroup from northern coastal China migrated to Japan, contributing to the Japanese population. This finding aligns with archaeological similarities between ancient peoples in the Americas, China, and Japan.
What makes the researchers so confident in their results
Dr. Li highlighted the strength of the study, noting the large number of samples they discovered and the complementary evidence from Y chromosomal DNA that showed male ancestors of Native Americans lived in northern China at the same time as the female ancestors.
However, he added that “more evidence, especially ancient genomes, are needed to answer” questions about the specific location in northern coastal China where this expansion occurred and the events that promoted these migrations.
This study adds another piece to the puzzle that is Native American ancestry, but many other elements remain unclear.
“The origins of several founder groups are still elusive or controversial,” said Kong. “Next, we plan to collect and investigate more Eurasian lineages to obtain a more complete picture on the origin of Native Americans.”
More about human migration across the Earth
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