Washington (AFP)

It is a game known to all: throwing a ball or a piece of wood so that his dog intercepts and reports the object, again and again, encouraged by a few caresses or words of congratulations.

Such scenes have most likely been repeated since the domestication of "man's best friend" 15,000 years ago.

But, according to a new study, some Cubs also know how to bring the ball back.

This discovery, published in the journal iScience, overturns the long-held hypothesis that the ability to interpret deeply human social behaviors is reserved for dogs, and results from a selection process due to breeding.

It was made by chance, when Swedish researchers subjected 13 cubs born from three different litters to behavioral tests.

The team has raised baby wolves and puppies since the age of 10 days to try to answer questions about the differences - and similarities - between the two species.

It was only within the third litter that the lead author of the study, Christina Hansen Wheat, of the University of Stockholm, noticed that eight-week-old cubs were also attentive when a stranger launched a ball asking them to bring it back - without having been trained before.

"When I saw the first cub bring the ball, I got goosebumps - wow, that's unexpected," she told AFP. "Then two others did the same, it was really exciting."

Three of the thirteen Cubs have shown that they can play this game consistently.

These variations in the response of wolves - ancestors of dogs - to human behavior could thus have been, from the outset, a key factor in their selection by prehistoric men.

According to the researcher, this discovery adds "a new piece to the puzzle" of canine domestication, a very changing field of research, the scientists disagree on the chronology, the geographical origin and the conditions which led to one of the partnerships. the most fruitful between man and the animal kingdom.

And since such a trait may be absent in the majority of wolves but present in others, a large number of them will have to be tested, she warns, in order to identify the gene (s) responsible for these differences.

© 2020 AFP