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Some wolf pups recently stunned scientists. These young wolves were willing to play fetch. NPR's Nell Greenfieldboyce reports on why a simple game for your dog is a surprising feat for a wolf.
NELL GREENFIELDBOYCE, BYLINE: Over 15,000 years ago, people somehow began hanging out with a now-extinct population of wolves. Wolves are large, dangerous carnivores. Yet they were the first animals that humans ever domesticated. They became our best friend, maybe by hanging around human camps to get scraps. Or maybe early humans kidnapped wolf puppies to raise them.
CHRISTINA HANSEN WHEAT: It's kind of hard to say. There's different theories out there. I don't think there's any real consensus about how we actually did this.
GREENFIELDBOYCE: Christina Hansen Wheat is a researcher at Stockholm University in Sweden. She's been studying wolves to better understand how domestication may have changed behavior. When the wolves were eight weeks old, she put them through a series of standard puppy tests normally used by dog breeders.
HANSEN WHEAT: Within this test battery, the puppy is introduced to a stranger. And the stranger then spends 15 minutes with the puppy.
GREENFIELDBOYCE: To see if the puppy is social, if it follows the person around, if it seems comfortable and it will respond when a person throws a ball and urges the dog to fetch.
HANSEN WHEAT: The fetching test just happened to be part of this.
GREENFIELDBOYCE: Two litters of wolf pups didn't fetch at all, which was just what the scientists expected from wolves, given that reading social cues from humans is thought to be a dog trait. But then she tested another litter. She was shocked to see one wolf chase the ball and bring it back.
HANSEN WHEAT: I still get goose bumps when I talk about this because it was such a surprise.
GREENFIELDBOYCE: And it wasn't just this one wolf. Two others from that same litter did it, too.
HANSEN WHEAT: That was very exciting.
GREENFIELDBOYCE: A report on these findings in the journal iScience says that maybe fetching behavior didn't emerge in dogs. Maybe it already existed in some wolves. Evan MacLean studies dog cognition at the University of Arizona.
EVAN MACLEAN: This is kind of a cute little observation that nobody has ever made before.
GREENFIELDBOYCE: To him, though, it looks less like a game of fetch and more like two separate wolf activities - chasing the ball and then later walking towards a person while carrying it. Still, he thinks this is intriguing because it shows how wolves can vary greatly in how they interact with people, something that likely played a huge role at the start of wolves' transformation into dogs.
Nell Greenfieldboyce, NPR News.
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