Dogs: So Nice, We Domesticated Them Twice
So, just where did dogs come from anyway?
When you think about it, it’s pretty amazing that an entirely different species has become so closely linked to humans that we treat them like family members and they give us their unconditional love and protection.
But could it be that we love dogs so much that we domesticated them… twice?
Historically, scientists have argued that dogs were domesticated in either one of two places: Europe or East Asia. As it turns out, they might both be right.
A study just published in the June issue of Science posits that all modern dogs are directly related to two or more wolf populations and that humans in two different areas of the world both came to the conclusion that these wolves could be domesticated.
The evidence for this, researchers say, all comes down to good old DNA. The study’s authors were able to extract one ancient dog’s entire genome from an incredibly well-preserved piece of 4,800-year-old inner-ear bone discovered in Ireland.
When they compared this to the mitochondrial DNA of 59 other ancient dogs, they discovered something surprising: an unexpected and deep genetic split between West Eurasian and East Asian dogs.
How did this all play out?
Scientists hypothesize that dogs were domesticated at separate times in East Asia and Europe. As humans began migrating from Asia to Europe, they took their dogs with them. Up until then, the Asian dogs were all descended from the same lineage, but some point, this branch split off into two, with one group of dogs breaking off and heading west with their human companions.
The apparent split occurred in Asia between 6,400 and 14,000 years ago, and that’s where we come to the AHA! moment — because fossil records show us that dogs existed in Europe long before the split in Asia ever happened. The researchers’ best theory is that as the dogs moved westward from Asia, they encountered the dogs that were already living in Europe and mated with them, creating a new offshoot in their lineage.
Pretty cool, right?
That said, this study is stirring up quite a bit of controversy in the scientific world, and a number of prominent researchers are arguing against it. The one thing that scientists can agree on is more that study is needed to determine which theory is correct.
At the end of the day, one thing is certain: no matter where or when it first occurred, we sure are thankful that our canine companions came to live with us all those millennia ago, because our lives are all the richer for it.
Christina Peden is a lifelong animal lover and avid wordsmith. She lives in Toronto with her boyfriend Ryan where they are proud pet parents to puppy, Matilda and cat, Oscar. In her spare time, she can be found enjoying Toronto, Canada's all-too-short patio season, taking advantage of the city's numerous parks or curled up with a good book.
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