The first dogs evolved from wolves in Asia — and maybe the Middle East — a study of ice age DNA suggests
A cohort of geneticists, led by researchers at the Francis Crick Institute, analyzed the genomes of 72 ancient wolves that were excavated across Europe, Siberia, and North America. The DNA spanned 100,000 years and 30,000 generations of wolves.
Then the researchers compared the wolf DNA to genomes of modern and ancient dogs. The dogs were most similar to gray wolves in Siberia about 13,000 to 23,000 years ago — during the last ice age.
“That’s consistent with a wolf population from Central Asia leading to the origin of dogs,” Adam Boyko, a canine geneticist at Cornell University, who was not involved in the study, told Insider. His own research analyzing the genomes of village dogs across the world — the semi-feral kind that aren’t bred for particular traits — has pointed to the same region as the origin of dog domestication.
“Now we’ve got this mirror image dog-wolf analysis, both pointing to Central Asia as an origin,” he said. Still, he cautioned, “I don’t think that the final story has been written yet.”
Ancient dogs in the Middle East, Africa, and Southern Europe also show ancestry from wolves in the Middle East, in addition to their Central Asian roots. That could indicate either a second instance of domestication in the Middle East, or dogs there interbreeding with wild wolves.
The researchers published their study in the journal Nature on Wednesday.
The new genetic history of ancient wolves shows evolution in real time
With their new library of ancient DNA, the researchers could see wolves changing over the ages.
“This is the first time scientists have directly tracked natural selection in a large animal over a time-scale of 100,000 years, seeing evolution play out in real time rather than trying to reconstruct it from DNA today,” Pontus Skoglund, study author and leader of the Francis Crick Institute’s ancient genomics lab, said in a press release.
They saw one gene variant, which affects the development of skull and jaw bones, go from an anomaly to showing up in every wolf’s DNA over a period of 10,000 years. Scientists think that variant is present in all wolves and dogs today.
The work is similar to the ancient DNA analysis that has revealed how genetic mutations, like the one that allowed humans to digest lactose, emerged in humans and spread across the globe.
Like Homo sapiens and Neanderthals, dogs and wolves have mingled and interbred as long as the two species have existed. That’s made it difficult for scientists to trace genetic traits passing from one species to the other, and even more difficult to pinpoint when and where dogs were first domesticated.
No modern-day wolf population is more genetically similar to dogs’ ancestors than any other modern-day wolf population. Overall, ancient wolves are more similar to other ancient wolves on the other side of the continent than they are to modern-day wolves living in the same areas. Ancient wolves traveled great distances and bred, sharing their genes across those distances.
“This connectivity is perhaps a reason why wolves managed to survive the ice age, while many other large carnivores vanished,” Skoglund said.
That connectivity also makes an especially tangled ball of genetic yarn for researchers to unravel as they try to link dog domestication to a single wolf population. This study adds to the evidence for a single instance of domestication somewhere in Asia.
The Francis Crick Institute researchers are now turning their attention to genomes from other locations that weren’t included in this study, in hopes of narrowing down where exactly domestication happened.
Boyko has still more questions about the domestication of Asian gray wolves, including how humans in the area at that time fit into the picture.
“After that happened is when we had the domestication of wheat, and the domestication of cats, and the domestication of cattle and pigs and all of the other species that go with being a modern human,” Boyko told Insider.
“But dogs were the first. To what extent do we need domestic dogs before we had agriculture? Or is it just by chance that it happened in that order? It’s kind of interesting to think about, staring into your dog’s eyes and wondering what actually brought the wolf out of the den and into the campsite.”
Read the original article on Business Insider