Dogs likely accompanied humans to America after the Ice Age.
Researchers shortened a timeline for when man’s best friend may have migrated to North America based on a 10,000-year-old dog bone fragment found in southeast Alaska.
The femur fragment, smaller than the size of a dime, was taken by surprise when scientists studied how climate changes during the Ice Age affected animal survival and movements, according to a University at Buffalo press release.
Researchers were sequencing DNA from a collection of hundreds of bones found in the region years ago when they realized that the tiny bone, originally thought to have come from a bear, contained DNA from a dog about 10,150 years ago, the release said.
“This all started with our interest in how Ice Age climate changes affected the survival and movement of animals in this region,” said Charlotte Lindqvist, the University of Buffalo evolutionary biologist, lead author of the study published Tuesday in the British journal The Royal Society. said in a statement. “Southeast Alaska would have served as a sort of ice-free stopover, and now – with our dog – we think early human migration through the region may be far more important than some previously suspected.”
Dogs were domesticated in Europe between 32,000 and 18,800 years ago. The findings suggest that dogs first migrated to America about 16,000 years ago, according to the study.
The bone’s DNA suggests it came from a dog that diverged from a Siberian dog as early as 16,700 years ago, scientists determined. The timing of that split coincides with a period when people may have migrated to North America along a coastal route that encompassed southeastern Alaska.
According to the study, there have been multiple waves of dogs that have migrated to America. Arctic dogs came from East Asia with the Thule, the ancestors of all modern Inuit peoples living in the Arctic. Siberian huskies were imported to Alaska during the Gold Rush, and other dogs were brought by European settlers.
But the exact time frame for when dogs first ventured into America was previously unclear. The bone’s findings coincide with when humans first came to America, after the last Ice Age when coastal glaciers began to retreat.
This suggests “that dogs accompanied the first humans to enter the New World,” the study said.
“The history of dogs has been intertwined with that of the people who domesticated them since ancient times,” the release stated.
However, the fossil record of ancient dogs in the North American continent is still incomplete, so any new remains that are discovered will provide important clues, said Flavio Augusto da Silva Coelho, a biological sciences student at the University of Buffalo.
Prior to the discovery, the earliest ancient dog bones found in the US were in the Midwest, Coelho said.