Ancient wolf DNA reveals the domestication history of dogs

For millennia, dogs have been a valued companion of humans. They’ve been used to hunt, defend livestock and as important social support. They’ve even been elevated to godly status.

But despite our long, shared history, it’s been difficult to recreate the history of their domestication. Researchers have claimed that dogs originated all around Eurasia, from Europe to the farthest reaches of China. But a study in Nature seems to finally clarify the muddled history of dogs a little.

Geneticists and archaeologists from 38 different institutions analysed 72 ancient wolf genomes from across Europe, Siberia and North America, spanning the past 100,000 years.

They concluded that dogs were domesticated around the time of the last ice age, approximately 15,000 years ago. By comparing their ancient DNA with modern wolf DNA, they were able to show a strong relation to East Asian wolves.

Because wolves are a highly mobile species, it’s difficult to say exactly where dogs originated unless ancient wolves from the population that led to modern dogs are sequenced. But the results definitively suggest that dogs were domesticated somewhere in Asia.

Dogs were (possibly) domesticated twice

Another intriguing finding in the study is that European, African and Middle Eastern wolves share up to half their DNA with West Asian wolf populations.

There can be two explanations for this.

Explanation one is that dogs were domesticated at least twice. At some point, separate dog populations interbred, leading to genetic mixing.

Another explanation is that some dogs from the Asian point of origin interbred with Middle Eastern wolves and that this dog population then spread across Europe and Africa.

At the moment, it’s impossible to rule out either explanation. For that, researchers need individuals from the wolf population with which European and African dogs are related — and so far, this population hasn’t been located.

The researchers didn’t study all ancient wolf populations available, and completing the picture by adding more wolf populations is one of the areas that will most likely see future research. The archaeologial recovery of new wolf and dog fossils will also help researchers recreate the domestication history of dogs.

The study is not the last word on the history of dogs, but it provides a strong foundation from which to build.

Source: Bergström, A., Stanton, D.W.G., Taron, U.H. et al. Grey wolf genomic history reveals a dual ancestry of dogs. Nature 607, 313–320 (2022). https://doi-org.ep.fjernadgang.kb.dk/10.1038/s41586-022-04824-9.