Dogs May Have Been Domesticated Twice, New Study Argues

Al Barry / Stringer / Getty Images
Al Barry / Stringer / Getty Images | Al Barry / Stringer / Getty Images

Scientists have long been trying to pin down the origins of man’s best friend. Some analyses contend that domestic dogs first appeared in Central Asia, while others argue that they evolved from wolves in Southeast Asia or even in Europe. A new study changes the argument. It argues that dogs were actually domesticated twice, from two different wolf populations, one in East Asia and one in Europe. 

The University of Oxford–led study, published in Science, examined the bones of a 4800-year-old dog discovered in Ireland. Researchers compared the sequenced genome from that dog to mitochondrial DNA from 59 dogs dating back as far as 14,000 years ago, and to the genetic expressions of 2500 modern dogs.

They found a genetic split that suggests that dogs came from two different wolf populations on opposite sides of Eurasia. At some point, dogs from Asia migrated westward, interbreeding and eventually replacing many of the earliest European dogs, which is why the genetic split of the population seems to appear years later than the first archaeological evidence of dogs in Europe would suggest.

This is still just a hypothesis, and since the evidence for the origins of dog domestication has been so muddled before, there will need to be more research to cement its validity. But it would provide an explanation for the contradictory findings of previous studies. “Maybe the reason there hasn't yet been a consensus about where dogs were domesticated is because everyone has been a little bit right,” as one of the study’s senior authors, Oxford professor Greger Larson, said in a press statement