Researchers have stumbled upon the oldest domesticated dog remains found in the Americas, which suggests man's best friend may have accompanied the first humans to the "New World." Mitochondrial DNA from the canine femur fragment found along the southeastern Alaskan coast shows its owner lived about 10,150 years ago, per a new study. That makes the dog slightly older than a canine group found to have roamed what is now Illinois some 9,910 years ago, per National Geographic. That raises the question: Just when did the first dogs arrive in the Americas? There's not a clear answer, but this bone does tell us a lot. It comes from a lineage that broke off from Siberian canines—believed to have been domesticated around 23,000 years ago, per CNN—sometime after 16,700 years ago, around the time humans moved from Siberia to the North American coast.
This raises the possibility that dogs accompanied humans as coastal ice was retreating at the end of the last Ice Age, before other dogs arrived via continental migrations. "The coastal edge of the ice sheet started melting at least around 17,000 year ago, whereas the inland corridor was not viable until around 13,000 years ago," says Charlotte Lindqvist, an evolutionary biologist at the University of Buffalo, per CBS News. "And genetic evidence that a coastal route for the first Americans over 16,000 years ago seems most likely. Our study supports that our coastal dog is a descendant of dogs that participated in this initial migration." National Geographic notes dogs might have served humans as hunters, protectors, carriers, and friends, but also as fur and food sources when times got tough. The Alaskan dog likely ate fish, whale, and seal meat, suggesting it also benefited from the partnership. (Arctic dogs can also be traced to Siberia.)