A new twist in the story of dog origins.
Precisely where the transition from wolves to pampered pets took place has long vexed scholars. Some believe humans originally domesticated wolves in Europe, and others claim it happened in Asia.
Researchers report in the journal Science that a new genetic analysis of canines suggests that dogs were domesticated from two separate wolf populations — one in Asia and one in Europe.
An international team of researchers began by sequencing the genome of a 4,800-year-old Irish dog, based on ancient DNA extracted from remains of its inner ear bone. The team also obtained DNA from 59 dogs that lived between 14,000 and 3,000 years ago and compared it to modern dog DNA.
With all of these data, the researchers created a canine family tree, which reveals a deep split between European dogs (like the golden retriever) and Asian dogs (like the Shar Pei).
“Animal domestication is a rare thing and a lot of evidence is required to overturn the assumption that it happened just once in any species,” said senior author Greger Larsen from Oxford University, in a press release.
“Our ancient DNA evidence, combined with the archaeological record of early dogs, suggests that we need to reconsider the number of times dogs were domesticated independently.”
At some point after their domestication, the Asian dogs were possibly transported to Europe with migrating humans, where they would have mixed with and partially replaced the earliest European dogs. Most dogs today are a healthy mix of the Eastern and Western dogs — a fact that may have made it challenging for previous studies to identify genetic signatures of dual origins.
“Maybe the reason there hasn't yet been a consensus about where dogs were domesticated is because everyone has been a little bit right,” said Larsen.
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