TPhoto: Ben Potter, University of Alaska, Fairbankshe mitochondrial DNA of two infants buried 11,500 years ago in Alaska is complicating the genetic puzzle of Native American history.

The new University of Utah study, published this week in the Proceedings of the National Academy of Sciences, adds a new wrinkle to the settlement of North and South America from travelers across the frozen bridge over the Bering Strait.

The new DNA samples taken from the bones of a weeks-old baby and a preterm fetus identify their genes with various Native American groups stretching from the Yukon, down to Bolivia and Peru.

The theory is the “Beringian standstill model,” by which the first Native Americans came across the bridge – then remained up to 10,000 years in the same place before quickly traveling down along the Western hemisphere, they said.

“We see diversity that is not present in modern Native American populations of the north and we see it at a fairly early date,” said Dennis O’Rourke, an anthropologist and senior author of the paper. “This is evidence there was substantial genetic variation in the Beringian population before any of them moved south.”

Read more: Not Just One: Genes Show Second Prehistoric Population Migrated to Americas

The mitochondrial DNA, holding just the maternal lineage, is hardy and survived the millennia in the interred bones.

It showed that the one infant was identified with a lineage known as C1b, which is found among the Pima of Arizona, the Ignaciano in Bolivia, the Delta Yuman in California, and the extinct Tainos of Puerto Rico.

The second infant had the common B2 lineage, which is found in 37 tribes: the Yakama, Shoshoni, Navajo, Zuni, the Aymara of Peru, and the ancient Fremont and Anasazi, too.

The newest genetic study comes on the heels of a Harvard study published in July which contends that the settlers of South America also genetically resemble peoples from Australia, New Guinea, and other Pacific islands. David Reich, the senior author of that paper, also found in 2012 that there were successful migrations from the top of North America which accounts for genetic variations.

Earlier this year, the famed “Kennewick Man,” an ancestor from 9,000 years ago, was linked genetically to current Native American groups in the area, continuing a legal and political back-and-forth over the remains, discovered in 1996 in Washington state.


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