Why Wolves Work Together While Wild Dogs Do Not
Contrary to popular belief, domestication has made dogs less likely to cooperate to get food than wolves
Anyone who’s watched a dogsled team in action knows that dogs are capable of teamwork. Many researchers even believe that due to domestication, dogs are likely more cooperative than their wild wolf cousins. But as Elizabeth Pennisi reports for Science, a new study shows just the opposite, suggesting that wild wolves work together much more coherently than dogs.
To compare the two species, Sarah Marshall-Pescini of the University of Vienna tested dogs and wolves at the Wolf Science Center in Austria, which houses a pack of 15 mutts and seven small packs of wolves. All of the animals are raised in semi-wild conditions. She tested the canines using the “loose string” test, which involves placing pairs of dogs or wolves in front of a cage with a tray of food in it. In order to slide the tray out of the cage, both animals had to pull on a rope simultaneously.
When the animals tested were not initially trained to pull the ropes, five out of seven wolf pairs were able to figure out the test and cooperate enough to get the food in at least one trial. For the dogs, only one pair in eight cooperated enough to figure out the test—and they only accomplished it in a single trial.
In a second test, the animals were briefly trained on how to tug the ropes. When tested again, three out of four wolf teams figured out how to pull the tray together. But dogs again failed, with only two out of six pairs able to get the food. And in those cases, they succeeded during just one trial. The researchers published their results in The Proceedings of the National Academy of Sciences.
“We were surprised at how little the dogs did cooperate,” Marshall-Pescini tells George Dvorsky at Gizmodo. “We expected a difference but perhaps we were not quite prepared at how big of a difference we saw."
Though dogs seemed engaged, they approached the food one at a time, "very respectfully waiting for one to finish before the other started," she says, which prohibited them from testing out teamwork. Meanwhile, the wolves cooperated well, working together on the level of chimpanzees, according to Helen Briggs at the BBC.
In some ways, the results are not surprising. Wolves are highly social and live in packs, raise their young together and hunt as a team. Dogs, when left to fend for themselves in wild or semi-wild conditions, raise their young on their own and look for food as individuals, not as a group.
The study also shows that researchers need to conduct more studies on free-ranging dogs, reports Ed Yong at The Atlantic. Similar studies of pet dogs show they work much more cooperatively, likely because they are trained or educated by their human companions. While most people in the United States think of dogs as the popcorn-stealing pal that watches movies in their lap, 80 percent of dogs in the world live wild in the streets of villages or agricultural areas.
“If I ask people to close their eyes and think of a dog, everyone thinks of a pet dog,” Marshall-Pescini tells Yong. “But pet dogs are a really recent invention and free-ranging dogs are more representative of the earlier stages of domestication. We need to base our theories on a different understanding of what a dog is.”
There are several theories for why semi-wild dogs aren’t as cooperative as wolves. As Yong reports, it's possible that in the process of domestication humans, rather than other dogs, stepped into the role of dogs' social partners. It’s also possible that the lack of cooperation is an adaptation to living in a human environment where the ability to grab a snack from the trash is more important than cooperating to take down an elk.
Another hypothesis is that dogs actively try to avoid resource conflict with each other, writes Dvorsky, and that prevents them from doing well on this particular task. Whatever the case, it sheds some light on the differences between the two related species and shows what needs to be investigated next.