You may have heard of the widely held belief that dogs look a lot like their owners—or vice versa, that people look a lot like their dogs. This idea has shown up in many different ways in pop culture, from the movie 101 Dalmatians to the game “Do You Look Like Your Dog?,” featuring matching dog and owner photos by animal photographer Gerrard Gethings.
But is it really true? It might sound like a myth, but several researchers have already investigated whether there’s any truth behind dogs looking like their owners.
Do dogs really look like their owners?
According to the BBC, “Michael Roy at the University of California, San Diego was one of the first psychologists to put the idea to the test. Going to three nearby dog parks, he photographed the pooches and the owners separately, and then asked a group of participants to try to match them up. Despite no additional cues, he found that they were able to work out who lived with whom with reasonable accuracy.”
This work has since been repeated many times, notably by Dr. Sadahiko Nakajima at Japan’s Kwansei Gakuin University.
Dr. Nakajima conducted a study using photographs of humans and their pups. He asked undergraduate students to match each person with their dog from the randomly ordered photographs. The results showed that the students correctly guessed the person and the pup by looking at the photos at a rate significantly higher than luck alone.
Dr. Nakajima’s research, published in 2009, found that there really is truth to the idea that dogs resemble their owners.
All in the eyes
Next, Dr. Nakajima wanted to find out why dogs looked like their owners. Which facial features did people use to correctly match dogs with their owners so accurately?
In another study, he covered up different facial features in the photos, such as the mouth and the eyes, and asked students to match dogs and their owners again. As HuffPost explains:
“The participants were randomly assigned to one of five different “masking” photo conditions, pictured below: no-mask (in which the human’s and the dog’s faces were unobstructed), eye-mask (the human’s eyes were blacked out), mouth-mask (the human’s mouth was blacked out), dog-eye-mask (the dog’s eyes were blacked out), and eye-only (where just the eyes of the human and the dog could be seen).”
The rate at which the students correctly matched the person with their dogs dropped significantly when the eyes in the photos were masked. This result supports the theory that the eyes are the most important feature connecting humans and our dogs.
Dr. Nakajima’s work was published in the journal Anthrozoös in 2013.
The reason behind why some dogs look like their owners
Why the eyes? It may be due to familiarity, or what psychologists call “the mere exposure effect.”
According to Dr. Nakajima, “a major reason of the dog–owner facial resemblance is the so-called ‘mere exposure effect,'” or the idea that a person might choose to get a dog who looks similar to themselves because of a preference for the familiar.
As humans, we tend to like things that are familiar to us. This could help explain why people with long hair might choose a dog with long, floppy ears, for example.
All this research suggests that the emotional bond we share with dogs might extend to looking like each other, too. It’s no wonder we think of dogs as humankind’s best friend.