A new study suggests that a single domestication event gave rise to the dog, the Washington Post reports. Previous work, though, has hinted that two domestication events took place.
In Nature Communications, researchers from the US and Germany report that they've sequenced the genomes of two ancient dogs found in Germany, one dating back to the Early Neolithic about 7,000 years ago and one from the End Neolithic about 4,700 years ago and compared them to a 5,000-year-old dog sample uncovered in Ireland and 5,649 modern dogs and wolves.
They found that the two ancient German dogs share continuity with each other and with modern European dogs.
They "looked like modern dogs, in particular like European dogs," senior author Krishna Veeramah from Stony Brook University tells the Post.
Based on the mutation rate of the older dog, he and his colleagues estimate dogs were domesticated some 20,000 years to 40,000 years ago, as dogs and wolves split between 36,900 years and 41,500 years ago and as eastern and western dogs split some 17,500 years to 23,900 years ago.
This, Nature News adds, challenges the earlier work that had suggested two origins for dogs based on their timing of the split between eastern and western dogs to 6,400 years to 14,000 years ago — before the appearance of dogs in Europe and Asia.