From an ancient fragment of bone:
The research reports that a bone fragment found in Southeast Alaska belongs to a dog that lived in the region about 10,150 years ago. Scientists say the remains—a piece of a femur—represent the oldest confirmed remains of a domestic dog in the Americas…
Researchers analyzed the dog’s mitochondrial genome, and concluded that the animal belonged to a lineage of dogs whose evolutionary history diverged from that of Siberian dogs as early as 16,700 years ago. The timing of that split coincides with a period when humans may have been migrating into North America along a coastal route that included Southeast Alaska…
The research adds depth to the layered history of how dogs came to populate the Americas. As Lindqvist notes, canines did not arrive all at once. For example, some Arctic dogs arrived later from East Asia with the Thule culture, while Siberian huskies were imported to Alaska during the Gold Rush. Other dogs were brought to the Americas by European colonizers.
The new study sharpens the debate on dog and human migration into the Americas.
“Our early dog from Southeast Alaska supports the hypothesis that the first dog and human migration occurred through the Northwest Pacific coastal route instead of the central continental corridor, which is thought to have become viable only about 13,000 years ago,” Coelho notes.
Charlotte Hsu, University at Buffalo, “How did dogs get to the Americas? An ancient bone fragment holds clues” at Phys.org
The paper is open access.