Now, the mystery may has been partially solved. In a paper recently published in Science, researchers report on the results of the analysis of 169 ancient DNA samples taken from fragments of human remains. From this research it appears that the Dorset were a unique people that thrived for over 4,000 years, but then quickly disappeared, but not through assimilation. Rather, it seems that the present-day Inuits are descendants of the Thule, but the Dorsets never mixed with the Thule.
Eske Willerslev, an evolutionary biologist at the Center for GeoGenetics at the University of Copenhagen and an author of the study said "This is surprising, because every time people meet each other we find evidence of sex between the people. But here we have a unique situation, where even though we know they must have been in touch with their neighbors, they chose to live in isolation."
The research also suggests that the Dorset people's ancestors came to Canada and Greenland from Siberia about 4,500 years ago in a separate migration from three previously known waves of migration that go back 15,000 years. It was earlier thought that they were descendents of one of these earlier migrant groups.
So, what happened to the Dorset? An analysis of their mitochondrial DNA shows that there was extensive inbreeding among them, and after thousands of years, the medical problems that this can cause may have led to their demise. Another cause of their extinction might be linked to food scarcity as a result of climate change. In the Arctic, minor temperature shifts can devastate marine life or make it inaccessible. In fact there is some archaeological evidence that this scenario nearly wiped out the Paleo-Eskimos earlier. Todd Disotell, a professor of archaeology at New York University told the New York Times,"When you're dealing with sea ice, just a few degrees can be transformative. Three bad winters in a row where you can't hunt seals, and you're in trouble."
There's also speculation that they were wiped out by the Thule people. The Dorsets left behind primitive stone tools and beautiful wooden an ivory figurines. The Thule people were more technologically advanced, having bows and arrows, whale-hunting tools and dogsleds. They also favored a military-style discipline, where as the Dorset were a conservative, simple people that would have been no match for the Thule.
The existence and demise of the Dorset people are a good example of the saying "Nothing lasts forever." Despite having survived thousands of years in a hostile environment the Dorset disappeared relatively rapidly. "This might be a good lesson for us today," said Disotell, "Long-term stability still means you can disappear. After 4,300 years, bam, you're gone in decades."