Two migrations of Native Americans' ancestors from "northern coastal China" to the Americas occurred in the distant past, according to the results of a new study published in Cell Reports earlier this week.
The first took place during the last ice age, between 19,500 and 26,000 years ago; while the second took place during the “subsequent melting period” between 19,000 and 11,500 years ago.
"The Asian ancestry of Native Americans is more complicated than previously indicated," Yu-Chun Li, molecular anthropologist at the Chinese Academy of Sciences and first author of the research in question, said as quoted in a press release. "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 researchers have arrived at these conclusions after investigating the lineage of ancient humans preserved in mitochondrial DNA which serve as an opportunity to "trace kinship through the female line."
The team also postulates that during the melting period, a group of people from northern coastal China also headed to Japan.
"We were surprised to find that this ancestral source also contributed to the Japanese gene pool, especially the indigenous Ainus," Li remarked.