The first humans to settle in the Americas took their dogs with them, according to new research into how canines were domesticated.
An international team has studied the archaeological and genetic records of ancient people and dogs.
Researchers led by archaeologist Dr Angela Perri, of Durham University, found that the first people to come to the Americas, more than 15,000 years ago from north-east Asia, were accompanied by their dogs.
They discovered that canine domestication likely took place in Siberia more than 23,000 years ago, and people eventually moved west towards Europe and east towards the Americas.
The Americas were one of the last regions of the world to be settled by people, by which time dogs had been domesticated.
Dr Perri said: “Dog domestication occurring in Siberia answers many of the questions we’ve always had about the origins of the human-dog relationship.
“By putting together the puzzle pieces of archaeology, genetics and time we see a much clearer picture where dogs are being domesticated in Siberia, then disperse from there into the Americas and around the world.”
Geneticist and co-author Laurent Frantz of Ludwig Maximilian University in Munich said: “The only thing we knew for sure is that dog domestication did not take place in the Americas.
“From the genetic signatures of ancient dogs, we now know that they must have been present somewhere in Siberia before people migrated to the Americas.”
And co-author and archaeologist David Meltzer of Southern Methodist University in Dallas, said: “We have long known that the first Americans must have possessed well-honed hunting skills, the geological know-how to find stone and other necessary materials and been ready for new challenges.
“The dogs that accompanied them as they entered this completely new world may have been as much a part of their cultural repertoire as the stone tools they carried.”
The findings are published in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).