Watch two dogs at play and you’ll notice that they seem to talk to each other, even engaging in a back and forth of similar excited gestures like bowing to initiate a play session, much like a pair of hairy fencers. Researchers in Italy decided to take this casual observation a step further, filming almost 50 interactions between dogs of various ages at a dog park and analyzing them to see if these mimicking behaviors were random or evidence of something deeper. Their study found that yes, dogs actually are having a conversation as they play, and the longer dogs know each other, the more closely they imitate each other, explaining why dogs with lasting relationships work and play so well together.
Researchers have explored interspecies and intraspecies bonds alike, with a particularly interesting study earlier this year showing that dogs and humans actually form a biochemical attachment, the result of millennia of domestication and breeding. This explains why people become so deeply attached to dogs and why cooperative endeavors like herding livestock or working with a service animal are so successful, with human and dog communicating through the bond to accomplish common goals. Other studies have looked at what’s known as “emotional contagion,” which is what this study focuses on.
We known that humans experience emotional contagion for a long time — the tendency to pick up on each others’ feelings and mirror them. For example, when you greet a friend and she grins, it can make you smile too as you feel more relaxed and happy. Being around someone who’s angry can provoke feelings of anger and unease, while seeing someone who is sad can evoke similarly sad feelings. Researchers in 2014 found that this also applied to emotional expression across species: When dogs heard a human crying, they became distressed, and they didn’t respond in the same way to more neutral sounds or white noise. This illustrated that dogs are attuned to human emotions, and they join a handful of other species including most primates, along with elephants, in expressing demonstrable emotional connections that can’t be attributed to coincidence. The research also suggests that other mammals likely do the same thing, especially in the case of domesticated animals, which have been selected for their human-friendly behavior.
The Italians looked at two different behaviors: The playful “bow” many dogs exhibit to invite each other to play, and the open-mouthed but friendly “grin” dogs display when they’re ready to have fun. To count as mimicking behavior, the other dog had to repeat the gesture within a second. They found that dogs who knew each other were more likely to return the gesture — think of two friends saying hi, versus strangers passing on the street — and they say it’s not just about empty repetition. It actually reflects a change in mood, as one dog’s playful behavior incites another’s, and it can spread through a group to create a bond or cooperative feeling. Emotional contagion can help animals unite, which increased chances of survival in the past and makes it fun to watch them play today.
Catching emotions like this means that dogs are also empathetic. While this isn’t news to anyone who’s spent time around dogs, this growing body of science is important for validating anecdotal evidence, which contributes to a better understanding of humane-dog bonds as well as those between canines. Learning more about normal dog behavior can help people like dog trainers, who may be faced with clients who exhibit stress behaviors or act out because they haven’t been well socialized, and it’s also incredibly valuable for people who train working dogs like service animals and livestock guardian dogs. For the rest of us, it’s Captain Obvious telling us what we already know: Dogs, like many other animals, form lasting connections with one another, and differentiate between friends, strangers and enemies.
Research like this is also important for another reason: Socially, it changes the way we view and talk about animals. Historically, and sometimes even today, many human societies regarded animals as objects without the capacity for emotion or even pain. Today, that understanding is changing, with a growing number of people understanding that animals communicate, have feelings, and experience both physical and emotional pain just like humans.
Photo credit: Eric Sonstroem