New genetic research on ancient bones reveals that a prehistoric population of hunters migrated into the high Arctic of North America and Greenland and survived for 4,000 years in almost complete isolation from the rest of humanity. Then, about 700 years ago, they vanished — either victims of genocide or simply out-competed by a new population of hunters with more advanced technology, the research indicates.
This is the tale of the Dorset culture. They were colonizers of a place where no humans had ever been — a harsh world that was rich in animal resources but largely covered in ice and gripped by the long night of the Arctic winter.
Their ancestors came from Siberia. They hunted musk ox, reindeer, seals and caribou. There were only a few thousand of them, living in small bands in what amounted to a geographic cul-de-sac at the top of the world. They had minimal contact with other cultures and they must have liked it that way.
“The Dorsets were the Hobbits of the eastern Arctic – a very strange and very conservative people who we’re only just getting to know a little bit,” said anthropologist William Fitzhugh, director of the Arctic Studies Center at the Smithsonian’s National Museum of Natural History and a co-author of the new report, published Thursday online in the journal Science.
The demise of the Dorsets coincided with the arrival of the Thule people, the ancestors of today’s Inuit. The Thule had larger boats and technology that could be used to hunt whales, and they had an almost militaristic social organization, Fitzhugh said.
“The Dorset people had no bows and arrows. They were, in a sense, sitting ducks,” he said. “They either were pushed out in the fringes of the Arctic area where they could not survive economically, or else they were annihilated in some way.”
There are many revelations in this new study. Anthropologists who studied artifacts in the Arctic had previously identified two distinct paleoEskimo groups, the Pre-Dorset/Saqqaq and, later in the archeological record, the Dorsets. But the genetic research shows that they’re the same people. Their artifacts look different because of cultural innovations, not because new people showed up from far away with new tools, materials and customs, the study suggests.
The textbook narrative of the Arctic also has long reported that there was a remnant of the Dorsets, known as the Sadlermiut people, living on the shores of Hudson Bay as recently as the early 20th century, and that in 1902 or 1903 the last of these people died from diseases to which they had no immunity. But the new report states that the Sadlermiut were not Dorset descendants. Rather, they were descended from the Thule people.
“It is surprising that the genetic data shows that Sadlermiut were Thule and confirms that the Dorset were indeed wiped out after the arrival of the Thule people. This contradicts both the archaeological literature as well as previous genetic work,” the study’s lead author, Maanasa Raghavan, a 29-year-old Canadian molecular biologist at the Natural History Museum of Denmark’s Centre for GeoGenetics, wrote in an e-mail.
The research shows that the ancestors of the Dorsets came from Siberia, starting about 6,000 years ago, migrating in watercraft across the Bering Strait. They kept moving to the east in pursuit of the big game that thrived in the Arctic after the end of the Ice Age. They certainly weren’t going to migrate south, because those regions were already inhabited by Native Americans.
“The high Arctic is a resource-rich place if you know how to use the resources,” said David Reich, a geneticist at Harvard Medical School who has studied the migrations of ancient people.
The peopling of the new world remains highly controversial. Reich, who was not involved in the new study, co-authored a paper in the journal Nature in 2012 that suggested that the Americas were populated in three distinct migrations of people from Siberia. But a newly published book on the 9,000-year-old skeleton known as the Kennewick Man suggests that people came and went from Asia along the northern Pacific coast almost continuously for thousands of years.
The new paper in Science argues that the Dorset people must represent a fourth migration pulse.
“The authors claim, but I think have not shown clearly, that there’s been a fourth wave,”Reich said.
The research looked at the mitochondrial DNA extracted from the bones, teeth and hair of 169 prehistoric individuals, and also took genetic samples from people living today in Siberia, the Aleutian Islands, Alaska, northern Canada and Greenland. The Dorsets were so isolated that they showed signs of inbreeding.
“It’s remarkable that there are so few connections made with Native Americans,” Fitzhugh said. “It seems to be that the combination of the high Arctic geography and the avoidance relationships between the Indian and the PaleoEskimo people contributed to this situation.”
The Dorsets disappeared rather abruptly, and there is no sign that people today in the Arctic inherited any Dorset genes. Any common genetic markers date to ancestral populations in Siberia.
The Dorsets also showed no genetic admixture with the Norse who began exploring Greenland about 1,000 years ago.
“We’re not really sure what happened to the Dorset,” Raghavan wrote by email. “Existing hypotheses include a violent end or diseases that the Thule might have brought with them -- but no concrete evidence to support one or the other.”