The internet might love itself some cat videos, but every dog has its day — and today that’s because of a new study that appeared today in Science suggesting that dogs became domesticated from wolves in Europe, rather than East Asia, and tens of thousands of years earlier than previously believed.
Modern dogs descending from wolves isn’t a new idea. As Carl Zimmer explains at the New York Times:
Scientists have long agreed that the closest living relatives of dogs are wolves, their link confirmed by both anatomy and DNA. Somewhere, at some point, some wolves became domesticated. They evolved not only a different body shape, but also a different behavior. Instead of traveling in a pack to hunt down prey, dogs began lingering around humans. Eventually, those humans bred them into their many forms, from shar-peis to Newfoundlands.
The question is when. Previous findings had suggested that canine domestication was linked to humans’ discovery/invention of agriculture. But that was under 10,000 years ago, suggesting that dogs might be a relatively recent addition to the animal kingdom. The new research posits the opposite: that wolves started dogging it up tens of thousands of years earlier, while humans were still mostly hunter-gatherers.
New Tricks on Old Dogs
To arrive at the new figure, the authors studied 10 ancient wolf-like fossils and 8 doglike fossils, analyzing their mitochondrial DNA. This type of DNA is much more prevalent in ancient remains than nuclear DNA is. That ancient DNA was then compared to DNA from modern dogs, wolves and coyotes. The modern dogs clustered into four distinct groups, senior author Robert Wayne of the University of California, Los Angeles, told NPR:
“Three of them group with our ancient dog or wolf sequences from Europe. One of them groups with modern wolf sequences but still from Europe,” says Wayne. “We really didn’t have any other conclusion that we could make except that dogs seemed to be domesticated in Europe.”
The researchers concluded that domestication took place between 19,000 and 32,000 years ago.
A Dog’s Life
But things aren’t as simple as they seem. Peter Savolainen of the Royal Institute of Technology in Sweden, proponent of a rival theory that dogs originated in East Asia, told Carl Zimmer:
“It’s not a correct scientific study, because it’s geographically biased,” he said. The study lacks ancient DNA from fossils from East Asia or the Middle East, and so it’s not possible to tell whether the roots of dog evolution are anchored in those regions. “You just need to have samples from everywhere,” Dr. Savolainen said.
Like any unsettled matter in science, all we can do is study the existing evidence and wait for more research and analysis. Wayne, for his part, is planning on following up by studying the nuclear DNA of the ancient animals, a much more difficult task, and looking for fossils outside Europe — but he’s sure it won’t change today’s main finding.
Whether his dogged determination vindicates this belief, only time will tell.
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