How did dogs become man’s best friend? Eye contact, study suggests.

Animal cognition experts from Azabu University in Japan offer neurological evidence to explain why humans and dogs get along so well.

Mikako Mikura
A student playing with Hook, a Labrador Retriever. His gazing behavior increased his owner’s urinary oxytocin (experiment 1) but his gazing behavior did not increase after administered oxytocin (experiment 2).

Could a staring contest make your dog love you more?

Not exactly, but new research suggests a direct correlation between eye contact and dog-human bonding. In a study published Thursday in Science, Japanese dog cognition experts show how prolonged “mutual gaze” fosters emotional bonds that appear to be correlated with a release of hormones in both dogs and and humans.

Humans have kept domesticated dogs for millennia, but the phrase “man’s best friend” only entered our vernacular in recent centuries. It’s a well-earned title, but an inexplicable one: for reasons unclear, no other interspecies companionship comes close.

To better understand the neurobiology behind human-dog companionship, a team of researchers from Azabu University in Sagamihara, Japan, placed a number of canine participants in a room with their owners. They instructed owners to touch, talk to, or gaze at their pets for a period of 30 minutes. When the time was up, researchers took urine samples from both pet and owner, which they tested for oxytocin levels. Oxytocin is sometimes called the “love hormone” – during mammalian reproduction and childbirth, it acts as a neurotransmitter, sending positive feedback to the brain. It is also associated with pair bonding.

“We think that in terms of nurturing or care taking, the human-dog bonding and parent-infant bonding is comparable,” co-author Takefumi Kikusui said. “Both of them have a same oxytocin-mediated positive loop.”

Surprisingly, Dr. Kikusui’s team found that simple eye contact was better at raising oxytocin levels than vocal communication or physical contact. So as much as your dog probably appreciates a good scratch behind the ear, eye contact has a deeper association with bonding.

To determine the origin of this bonding mechanism, researchers replicated the experiment with wolves – the closest living relative to the domestic dog. In those trials, eye contact did not result in significant oxytocin release. In other words, mutual-gaze bonding must have developed after modern dogs diverged from their wolf ancestors. Evan MacLean, a Duke University researcher studying animal cognition, says that dogs and humans could have coevolved this form of communication during domestication – which is thought to have occurred between 11,000 and 16,000 years ago.

“It’s relatively fast in the scheme of things,” Dr. MacLean said. “But under artificial selection, things can happen very quickly. For example, most of the dog breeds we know today, in all their splendid diversity, are the product of the Victorian era.”

In the second phase of the experiment, researchers gave dogs a nasal spray of oxytocin and placed them in a room with their owners and some strangers. Female dogs responded by gazing at their owners longer, which in turn raised the oxytocin levels of the owners. There was no discernable difference in males, for reasons still unclear, Kikusui says.

But for many canine enthusiasts, the research begs a more obvious question: will my dog love me more if I stare at it?  

“We think that dogs naturally have ability to show mutual gazing with humans,” Kikusui said. “But of course not all the dogs easily show this behavior. My guess is that if the owner and dog spend intensive and positive communication time – such as talking to the dogs, petting, giving treats – dogs usually pay attention to the owner.”

“Gaze has different meanings in different situations,” MacLean said. “So it’s great to gaze lovingly at your dog when it’s a natural bonding moment, but I wouldn’t spend too much time forcing this type of interaction outside of natural contexts. Believe me, most dogs will spend plenty of time looking at you quite naturally.”

You've read  of  free articles. Subscribe to continue.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.