We’re often amused when dogs and their owners seem to look alike—both have lanky limbs or shaggy locks, say. A recent study has found that dogs resemble their owners in an entirely different way: their personalities actually tend to be similar.
William J. Chopik, a social psychologist at Michigan State University and the study’s lead author, studies how human relationships change over time. Intrigued by the bond that people share with their pet dogs, he set out to examine those relationships and the dynamics within.
His study had the owners of 1,681 dogs evaluate their own personalities, and their dogs’ personalities, on standardized questionnaires. He found that dogs and their owners share personality traits. A highly agreeable person is twice as likely to have a dog who is highly active and excitable—and less aggressive—than someone who is less agreeable. The study also found that conscientious owners rated their dogs as more responsive to training and neurotic owners rated their dogs as more fearful. By contrast, “if someone is chill, their dog is chill," says Chopik.
Chopik points out the obvious challenge in doing this study: you can ask people questions about themselves, but with a dog, you can only rely on owners’ observations of their pets’ behavior. But owner biases—the idea that owners may project their own personalities onto their dogs—don’t seem to come into play. Similar studies have found that acquaintances (strangers, friends, dog walkers) tend to rate a dog’s personality in the same way as its owner. (Does your dog prefer you over anyone else? It's complicated.)
Why do these similarities exist? The study doesn't address causes, but Chopik has a hypothesis. "Part of it is the dog you pick, and part of it is the dog it ultimately becomes because of you," he says.
Chopik says that when adopting a dog, people tend to gravitate towards one that will naturally fit into their daily rhythms. “Do you want a rambunctious dog that needs a lot of interaction, or one that's more chill for a more sedentary lifestyle?" he says. "We tend to choose dogs that match us."
Then, whether through conscious training or just day-to day interactions, we shape their behavior—and they change as we change. "Our lifestyle changes trickle down," he says. (Read about how dogs pick up on human emotions.)
Behaviorist Zazie Todd, author of the website Companion Animal Psychology, says it’s important to note that the five main traits widely used for evaluating people’s personalities (extraversion, agreeableness, conscientiousness, negative emotionality, and open-mindedness) are not the same as the five personality factors used for dogs (fearfulness, aggression toward people, aggression toward animals, activity/excitability, and responsiveness to training). “But there are some really interesting links” between human and dog traits, she says, and qualities tend to match up.
"Even though you measure things in different ways, you find correlations," Chopik says. "That makes similarities harder to detect, but we found them anyway."
For example, while "extraversion" isn't a trait that maps cleanly onto an animal’s personality, extraverted people are typically more outgoing and energetic, so a dog being highly active and excitable is a close parallel.
Future research could potentially tease apart the two possible causes for the personality links. In other words, that chicken-and-egg factor. For example, are friendly, outgoing owners more likely to choose a less fearful-seeming dog? Or is their outgoing lifestyle more likely to rub off on a dog over time? "People who are more agreeable may take their dogs out and about more so that the dog is better socialized and more used to different things," Todd says. "It could be that people are shaping their dog's personalities, and this is the most interesting possibility for me."