Dogs and wolves evolved from a common ancestor between 9,000 and 34,000 years ago, a new study suggests.
The findings, published in the journal PLOS Genetics, examined the genomes of three gray wolves believed to be the ancestor of domesticated dogs – one from China, Croatia and Israel -- and the genomes for two dog breeds, a dingo from Australia and an African Basenji. The results revealed that the three wolves were more closely related to each other than dogs, suggesting that modern dogs and gray wolves descended from an older common ancestor.
“This is an incredibly rich new dataset, and it has allowed us to carry out the most detailed analysis yet of the genetic history of dogs and wolves,” said Adam Siepel, associate professor of biological statistics and computational biology at Cornell and a co-author of the paper said. “There are still many open questions, but this study moves the ball forward.”
The team compared the genomes of the dingo and the Basenji to the genome of a boxer from Europe that had previously been sequenced. The results suggest that the dogs were more closely related to each other than the wolves.
"One possibility is there may have been other wolf lineages that these dogs diverged from that then went extinct," study senior author John Novembre, an associate professor in the department of human genetics, said in a statement. "So now when you ask which wolves are dogs most closely related to, it's none of these three because these are wolves that diverged in the recent past. It's something more ancient that isn't well represented by today's wolves."
The findings suggest that the origin of domesticated dogs is more complicated than the commonly held belief that farmers domesticated friendly wolves that later evolved into modern dogs, HealthDay reports. The new study indicates that dogs may have lived with hunter-gatherers and later adapted to agricultural life once humans settled down.
"Dog domestication is more complex than we originally thought," Novembre said. "In this analysis we didn't see clear evidence in favor of a multiregional model, or a single origin from one of the living wolves that we sampled. It makes the field of dog domestication very intriguing going forward."
What made certain dogs and wolves outlast others is the next question to be answered. “This paper sets the stage for the next step in the study of dog domestication that tries to determine the genetic changes that enabled this amazing transformation,” Ilan Gronau, the study’s coauthor, said.