The debate over whether dogs were domesticated in Europe or Asia may finally be resolved after all these years.
Researchers recently found the remains of a 5,000-year-old dog in Ireland, suggesting dogs could have been domesticated twice, including once in Asia and another time in Europe or the Near East. According to Science, the bone of the 5,000-year-old dog was a game-changer in the debate.
Project leader and University of Oxford evolutionary biologist Greger Larson told Science:
“I was like, ‘Holy shit!’ We never saw this split before because we didn’t have enough samples.”
The inner ear bone of the specimen was dug up from Newgrange, a large dirt field the size of a football field located on the east coast of Ireland. The mound of dirt and stone was built around the same time as Stonehenge.
Using the bone, a research team led by Laurent Frantz, an evolutionary geneticist at the University of Oxford, was able to sequence the ancient dog’s entire nuclear genome. It is the first complete genome of such a specimen to be published. The analysis was then compared to nuclear DNA of 605 modern dogs and wolves to calculate a genetic mutation rate for canines.
Humans are believed to have domesticated dogs in Asia more than 14,000 years ago. The Asian dogs purportedly migrated west through Eurasia, likely with people, between 6,400 and 14,000 years ago. Archaeological remains, however, date domesticated European dogs over 15,000 years ago. That’s 1,000 years before the Eurasian migration occurred.
While the findings suggest that there were two separate domestications that occurred, European ancestry in modern dogs may have been completely erased. Frantz said:
“We don’t know if the dogs that evolved [early] in Europe were an evolutionary dead end, but we can safely say that their genetic legacy has mostly been erased from today’s dogs.”
The analysis revealed that a decrease in genetic diversity in Western dogs may have led to a dramatic decline in their population.