by The story of how gray wolves became today’s pet dog has received a new twist, with research suggesting that our furry companions arose from not just one population of wild ancestors, but two.
Dogs were the first animals to be domesticated by humans, an event believed to have happened between 15,000 and 30,000 years ago when humans lived as hunter-gatherers.
“Most other animals were domesticated after the advent of agriculture,” said Dr. Anders Bergström, first author of the research at the Francis Crick Institute. “I think it’s a very fascinating thing that humans in the ice age have come out and formed this relationship with this ferocious predator.”
But how the process occurred remains unclear.
“We don’t know where it happened, what was the human group that did this, if it happened once or several times and so on,” Bergström said. “So it remains one of the great mysteries of human prehistory.”
The latest study is not the first to investigate the puzzle. Among previous work, a recent study suggested that wolves were independently domesticated in Asia and Europe, but only the former contributed to the ancestry of modern dogs.
“A key finding of our study, by contrast, is that dogs have dual ancestry,” said Bergström.
Writing in the journal Nature, Bergström and colleagues report how they analyzed 72 genomes from ancient wolves that lived in Europe, Siberia and North America up to 100,000 years ago, 66 of which were sequenced for the first time. The team compared them with genomes from primitive and modern dogs.
The results reveal that, in general, the dogs are genetically more similar to the ancient Siberian wolves, although these are not direct ancestors.
“It basically suggests that the dogs would have been domesticated somewhere in Asia,” Bergström said, though he said it’s not possible to pinpoint the location precisely.
But while the ancestry of some of the earliest dogs, such as those from Siberia, the Americas, East Asia, and northeastern Europe, seemed to be rooted solely in the wolves of Asia, others, particularly those from Africa and the Middle East. , and to a much lesser extent in Europe, were found to have an additional genetic contribution from a population of western gray wolves.
“The largest number of this second source of ancestry is found in a 7,000-year-old ancient dog from Israel,” Bergström said.
Additionally, he said, the contributions of this western wolf population are seen in all modern dogs today, although it is higher in those from the Middle East and Africa, such as the Basenji breed.
But questions remain. “We still can’t say if there were two independent domestication events followed by the merging of those two populations, or if there was a single domestication process, followed by a mixture of wild wolves,” Bergström said, adding that there is still work to be done to pin down. The geographic origins of our canine companions.
“The search continues to narrow down exactly where the dogs come from,” he said.
