Dogs use our gestures as cues

Dogs are excellent at reading the meaning of human gestures. Even chimpanzees—despite being our closest living relatives—do not understand us as well as dogs do.

Research conducted at the Department of Evolutionary Anthropology at the Max Planck Institute (2012) showed that chimpanzees do not understand the human gesture of pointing to an object, while dogs easily grasp its meaning. Moreover, they can interpret a pointing gesture using only visual cues.

Later studies revealed that dogs can also respond to the source of a human voice alone. In one study, researchers compared how well chimpanzees and dogs understood human cues. A person would point to one of two objects located in a place inaccessible to the human, but within the animal’s reach (eliminating the possibility of simply following hand movement). If the chimpanzee or dog chose the correct object, they were rewarded with a treat (chimpanzees received fruit juice or peanuts, while dogs received dog food). It turned out that chimpanzees chose objects randomly, ignoring human gestures, even though they wanted the treat. Dogs, on the other hand, had no trouble interpreting the gesture.

Chimpanzees know what others can and cannot see, and whether others are watching them. However, when trying to achieve their goals, they tend not to pay attention to people. Wolves, even those raised by humans, are also unable to interpret human gestures, whereas dogs can do so at a very young age.

Scientists believe that this is a specific evolutionary adaptation in dogs, resulting in a sensitivity to human forms of communication. Natural selection during domestication made them perfectly suited to a new niche—the human environment. Researchers suspect that this “gift” for reading human gestures may be innate, as even 6-week-old puppies without any special training possess it. Furthermore, dogs respond not only to a hand pointing at an object, but also to a human’s gaze directed at the object. Using eye-tracking technology, it has been shown that dogs can follow a human’s gaze just as well as six-month-old infants (Kaminski, Max Planck Institute for Evolutionary Anthropology, 2012).

Dogs also clearly know when we’re looking at them. A whole series of experiments (conducted, among others, at the University of Vienna and the University of Portsmouth) confirmed that dogs are more likely to disobey in a dark room than when the light is on, and also when the person nearby is reading a book or watching TV, compared to when they’re watching the dog.

Dogs are experts at reading human facial expressions. Studies using brain imaging (fMRI) have shown that dogs use a specialized brain region to process information about human faces (Berns, Emory University, 2013). It was previously believed that such specialization was reserved for humans and some primates.

Scientists believe this way of processing information about human faces is innate in dogs. If it were the result of conditioning—associating faces with food—it would activate the brain’s reward area, but that doesn’t happen.

Dogs as a species have co-evolved with humans for thousands of years and have developed a unique interspecies communication system with people.

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Gregory Berns, How Dogs Love Us: A Neuroscientist and His Adopted Dog Decode the Canine Brain, New Harvest 2013

Katharina C. Kirchhofer , Felizitas Zimmermann, Juliane Kaminski, Dogs (Canis familiaris), but Not Chimpanzees (Pan troglodytes), Understand Imperative Pointing, PLOS 8.02.2012