Many studies and discoveries focus on searching for the first Americans. Less popular but equally important has been research into how and when the Arctic was settled - the last region of the Americas known to have been populated.
     Archaeological and cultural evidence points to migrations of several different groups into the region, going back as far as 6,000 years for the earliest arrivals of the Palaeo-Eskimos from across the Bering Strait from Siberia.
     Maanasa Raghaven of the University of Copenhagen and colleagues have analysed 169 ancient human bone, teeth and hair samples from Arctic Siberia, Alaska, Canada, and Greenland, comparing them to samples from two present-day Inuit from Greenland, two Nivkhs, one Aleutian Islander, and two Athabascans. Their conclusions support the model of the arrival of Palaeo-Eskimos into North America as a separate migration from those which gave rise to Native Americans and Inuit, but suggest they shared a common Siberian ancestor.
     "We show that Palaeo-Eskimos (approximately 3000 BCE to 1300 CE) represent a migration pulse into the Americas independent of both Native American and Inuit expansions," the authors write. "Furthermore, the genetic continuity characterising the Palaeo-Eskimo period was interrupted by the arrival of a new population, representing the ancestors of present-day Inuit, with evidence of past gene flow between these lineages. Despite periodic abandonment of major Arctic regions, a single Palaeo-Eskimo meta-population likely survived in near-isolation for more than 4000 years, only to vanish around 700 years ago."
     The researchers show evidence for gene flow between the Palaeo-Eskimos and the Neo-Eskimo Thule culture - likely among a common ancestral population in Siberia, and not in the Arctic, where these two groups were largely separated.
     The study suggests a complex interplay between genes and culture, helping to provide a clearer picture of how the Arctic was settled.

Edited from Popular Archaeology (28 August 2014)