By Eric Sorensen, WSU science writer
PULLMAN, Wash. – With help from a Washington State University population geneticist, Danish researchers have concluded that North America and the Arctic were settled in at least three pulses of migration from Siberia. First came the ancestors of today’s Native Americans, then Paleo-Eskimos – the first to settle in the Arctic – followed by the ancestors of today’s Inuit.
The research, published in the journal Science, settles nearly a century of debate over Arctic settlement and whether today’s Inuit are related to Paleo-Eskimos, who disappeared 700 years ago. That’s about the time the technologically superior Inuit reached Greenland, but the researchers could not tie the disappearance of the Paleo-Eskimos to the Inuit’s arrival.
Cultural vs. genetic continuity
The study clearly shows that change in the Paleo-Eskimos’ tools and culture, which in archaeology is often interpreted as a result of migration, did not stem from new people. The Paleo-Eskimos lived in near-isolation for more than 4,000 years, and during this time their culture developed in such diverse ways that it has led some to interpret them as different peoples.
“Through this study, we are able to address the question of cultural versus genetic continuity in one of the most challenging environments that modern humans have successfully settled – and present a comprehensive picture of how the Arctic was peopled,” said Maanasa Raghavan, a researcher at the University of Copenhagen’s Centre for GeoGenetics and lead author of the study.
“It is indeed fascinating that we are able to learn more and more about our history with genomic data,” said Omar Cornejo, an assistant professor of genetics in WSU’s School of Biological Sciences and study co-author.
Part of Clovis genome project
He said the study is part of a large collaborative project that led to the publication earlier this year of the Clovis genome. The larger study is aimed at understanding the movement of people throughout the globe, especially the peopling of parts of the world that we know the least about, like the Americas.
Cornejo contributed to the recent study by inferring the ancestry of different peoples from the modern-day genomes of people from Greenland, Arctic Canada, Alaska, the Aleutian Islands and Siberia.
“As populations migrate and mix with already differentiated populations, the genome becomes a mosaic of different ancestries,” he said. One part of an individual’s genetic makeup will have one ancestry and another part of the genome a different ancestry.
“My role was to perform inferences of this mosaic of ancestries along the genomes to perform the analysis of diversification using only those regions that would be informative about the process of peopling of the Arctic,” he said.
Omar Cornejo, WSU population geneticist, 509-335-0179, firstname.lastname@example.org