Study sheds new light on origins of Arctic inhabitants

The Arctic was the last region on earth to be colonized by humans and many of its mysteries endure.

Now a new study sheds some light on the human history of the land, thanks to modern DNA technology.

“We’re trying to learn more about the origins and the ancestral ties between human populations that migrated into Canada and Greenland several thousand years ago, with populations further west in Alaska,” says Geoffrey Hayes, a geneticist at Northwestern University in Illinois and one of the authors of the study.

Archeologists have long held that the North Slope of Alaska was the most likely place that those first inhabitants entered the Arctic some 4,500 years ago.

The DNA study by Hayes and his colleagues bolsters the case. It’s is the first evidence that genetically ties Iñupiat and Inuit populations throughout Alaska, Canada and Greenland back to the North Slope.

The study, published in the American Journal of Physical Anthropology, found a genetic link to both the Paleo- and Neo-Eskimos that inhabited the land before European contact with today’s Inupiat population of the North Slope. Nowhere else did they find the DNA remnants of those first settlers, including the Dorset people that once lived in the Canadian Arctic.

That suggests that the North Slope served as a central repository for two waves of migration, from the North Slope and east to Canada and beyond.

The team gathered mitochondrial DNA - the strand inherited from the mother – from 151 residents of eight different Iñupiat communities on the North Slope of Alaska. They compared them to other Inuit populations in Siberia, the Aleutian Islands, Canada, and Greenland.

The research was invited by the local Inupiat of Barrow, Alaska.

As global warming tightened its grip on the Arctic, pushing the pack ice further from land, remnants of a pre-historic village near Barrow were being lost as the earth eroded into the ocean.

Worried that these rare clues to Arctic history would be lost forever, the Iñupiat community invited archeologists and then geneticists to help them rebury the human remains and unlock the mysteries within.

“There was an interest from the local community that, as long as archeological work was going on to recover these remains, that it was an opportunity to perform scientific studies to learn a little bit more about these ancestors,” says Hayes, who originally hails from the Edmonton area.

The results confirm what archeologists have long found, he says – that there were two waves of migration.

The first, about 4,500 years ago, were the Paleo-Eskimos. The second, about 800 years ago, were the Neo-Eskimos that are genetically indistinguishable from Inuit today.

The Neo-Eskimos, which included the Thule, had more advanced technology. With kayaks and tools, they hunted whales.

The Neo-Eskimos quickly adapted to and adopted the Arctic as their home. Within a few hundred years – “on the time-scale of the archeological record – practically overnight” – the ancestors of modern-day Inuit had spread from the North Slope to Greenland.

The genetic profiles also bolster the case for a back migration.

It would be expected that the people who are closer geographically would be closer genetically to one another, Hayes says.

“What we actually find is that the people of the Alaskan North Slope show a higher degree of similarity with populations in Greenland than they do with some of their own Canadian neighbours,” he says.

It’s something the Inupiat and Inuit already suspected.

“On more than one occasion we had participants of our study tell us that they could understand the Greenland dialects better than they could understand the Canadian dialects,” Hayes says.

There are ongoing studies looking at the Y chromosomes, which males inherit from their fathers, and the nuclear DNA markers that make up the remainder of the genome.

Those will help paint a fuller picture of a fascinating people.

“The North American Arctic is one of the very last places that gets colonized by humans,” Hayes says. “It’s a very difficult place to make a living and feed your family… but they figured out how to do it and were quite successful at it.”