Earlier this year, researchers found new support for this second idea when they measured the extent to which the ability to follow pointing gestures runs in dog families. Puppies who were more closely related to each other scored more similarly on the pointing test, which indicates that their scores could be partly explained by their genetics.
The ability of dogs to complete this task could be a product of domestication. Humans, intentionally or unintentionally, could have prompted dogs to become more effective communicators; people could have purposefully bred the friendliest dogs with each other, or, alternatively, the friendliest individuals could have been the most successful at living with humans. Or, the ability could be inherited from the common ancestor of dogs and modern-day wolves. To distinguish between these two possibilities, and to limit the influence of environmental factors, researchers have tried to compare dog and wolf puppies who were raised similarly. A 2008 study found that the dogs did better than the wolves on the pointing task, but a paper published the following year failed to replicate that difference.
This new study, which has a far larger sample size and compares wolves with more human contact to dogs with less contact, solidifies the conclusion that dogs are indeed better at this task than wolves, says Juliane Bräuer, head of the DogStudies Lab at the Max Planck Institute for the Science of Human History. “It was quite a big sample size, especially for the wolves,” she says. “To find testable wolves is always a challenge.”
Dogs’ abilities to follow pointing cues, then, appear to be a product of domestication—there’s an important genetic difference between dogs and wolves at work here. But just where genetics enters the picture remains an open question. Hare thinks that the key element is an evolved reduction in the natural fear that wolves have toward humans. (“Wolves are giant wusses,” Callahan-Beckel says.) As pack hunters, wolves need to be capable of coordinating with other members of their species. Hare believes that, during the process of domestication, dogs expanded their potential set of coordination partners to include people. “Dogs inherited a skill set at understanding others from wolves,” he says. “When fear was replaced by an attraction, those skills became enhanced.”
But perhaps dogs are simply more inclined to learn from humans, and do so incredibly quickly. In support of this second possibility, Wynne notes that the older dog puppies in the study performed better on the pointing task than the younger ones, which suggests that some learning was taking place.
In general, Wynne finds it difficult to believe that dogs have an ingrained ability to understand human gestures or human intentions. “It’s just absurdly unlikely that dogs could be born with an innate ability to follow human pointing gestures, when our own children are not born with an ability to follow human pointing gestures,” he says.
Both Hare and Wynne agree, however, that there is one major, striking difference between dogs and wolves, regardless of how they are raised: Dogs are far, far more attracted to humans. The wolves that Callahan-Beckel and Callahan raise will often, as adults, let their rearers rub their bellies and scratch them behind the ears. Strange humans, however, are a different story. In the study, dog puppies were 30 times more likely to touch unfamiliar humans than wolf puppies were.
Some wolves will see Callahan-Beckel and Callahan as their moms for life and greet them the way a pet dog might greet its owner arriving home from work. But others reveal their genetic history when they ultimately come to view their rearers as a leader to be overthrown. This happened recently for Callahan-Beckel, when Adam, a wolf she had raised, became the leader of his pack—and then decided he was the boss of her as well.
“I still love Adam. I still love him so much,” Callahan-Beckel says. “And I walk up to the fence [saying], ‘Oh, Adam, that’s my good boy,’ and he hits the fence as hard as he can, roaring, with his tail up, trying to kill me. And it’s just the way they are.”
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