Document type : News item published in Science
Author: David Grimm
Scientists have known for more than 2 decades that dogs understand the logic behind a surprisingly complex gesture: When we point at something, we want them to look at it. That insight eludes even our closest relatives, chimpanzees, and helps our canine companions bond with us. But it’s been unclear whether pooches acquire this ability simply by hanging out with us, or it’s encoded in their genes. […]
If social intelligence is genetic, dogs should display it at a very young age. And there shouldn’t be any learning required.
That's what MacLean and his colleagues found. The scientists partnered with Canine Companions for Independence, which breeds dogs to assist people in the United States with post-traumatic stress disorder and physical disabilities. The group loaned the researchers 375 8-week-old Labrador and golden retriever pups: They were just old enough to participate in the experiments, but young enough to have had very little interaction-and thus experience or learning-with people.
The researchers put the puppies through three tests. First, they performed a classic pointing experiment, placing the young dogs between two overturned cups-one containing a treat-and pointing to the one with the treat. The animals understood the gesture more than two-thirds of the time, approaching the performance of adult dogs. But they didn't get any better over a dozen rounds, suggesting they were not learning the behavior, MacLean says.
In a second experiment, a researcher stood outside a large playpen and, for 30 seconds, engaged in the kind of high-pitched "puppy talk" familiar to almost anyone who has owned a dog: "Hey puppy, look at you! You're such a good puppy." The animals spent an average of 6 seconds staring at the person. Such eye contact is rare among mammals-including the pups' ancestors, gray wolves-and it's an important foundation for social interaction with people.
In a final test, the researchers taught the puppies to find food in a plastic container, then sealed it with a lid. In contrast to adult dogs, which usually give up after a few seconds and look to humans for assistance, the pups rarely gazed at their scientist companions for help. "Puppies seem to be sensitive to receiving information from humans," as the other experiments show, MacLean says, "but they may not yet know that they can solicit help from us."
To confirm that the puppies' successful behaviors were genetic, the researchers analyzed their pedigrees to see how related each dog was to the others. Then they compared this relatedness with the dogs' performance on the tests. Approximately 43% of the variation in performance was due to genetics, the team reports today on the preprint server bioRxiv.
That's on par with the heritability of cognitive traits like IQ in people, MacLean says. "It's about as hardwired as things in psychology come."
"It's a really high number for a complex trait like behavior-it's a pretty big deal," agrees Noah Snyder-Mackler, an evolutionary biologist at Arizona State University, Tempe, who has collaborated with MacLean in the past, but was not involved with the current study. He says the finding suggests people strongly selected for these abilities in the past, paving the way for dogs to become the human mind readers they are today.
Link to scientific article (not yet peer-reviewed): Cooperative Communication with Humans Evolved to Emerge Early in Dogs
