There are few diversions more genuine than that of a dog that collects and returns a ball thrown by its owner. Until now, it was believed that the ability to interpret human social cues, such as those required by a search game like that, were acquired by dogs after their domestication at least 15,000 years ago. However, an experiment conducted with wolf cubs has completely surprised scientists. The wolverines were able to play ball with unknown humans as naturally as a labrador or a poodle. The unexpected results, published in the magazine « iScience », indicate that the specimens that demonstrated this property could be the ones chosen by humans to have them as a company, features that were later enhanced in dogs.
The findings were made by chance when Hansen Wheat, a researcher at the University of Stockholm (Sweden), and his team worked with thirteen wolverines from three different litters to evaluate various behaviors. In one of those tests, an experimenter whom the puppy does not know throws a tennis ball in a room and, without the benefit of any previous experience or training, encourages the animal to pick it up and bring it back.
The researchers did not expect the wolverines to know how the game worked. In fact, the first two litters they worked with showed little or no interest in the ball, much less recover it. However, in the third litter, three eight-week-old puppies not only went for the ball, but also responded to the stranger’s signals and brought them back.
« When I saw the first wolf cub retrieve the ball, I literally got goosebumps, » Hansen acknowledges. «It was very surprising, nobody expected it. And it was especially surprising that the wolves recovered a ball for a person they had never seen before, ”he emphasizes.
The finding has important implications in understanding how dogs were domesticated, and in the selective pressures to gather beneficial traits in them. This directed play behavior, which was believed to have arisen in dogs after domestication, may have already been found in wolves. Precisely, the wolf cubs that showed it could have been chosen as a company for humans, a feature that would also be a selective advantage in the early stages of dog domestication.
The team will continue to work with the data it has collected over three years raising wolves and dogs in identical conditions to learn even more about their differences and similarities in behavior.