Horses and humans share facial expressions, study says

Horses communicate with an extensive repertoire of facial cues, a new study finds.

AP Photo/Mel Evans
Assistant trainer Jimmy Barnes holds Triple Crown winner American Pharoah as they stand in the stable area at Monmouth Park in Oceanport, N.J., Aug. 1, 2015.

Long faces aside, horses may be more expressive than we thought.

According to a new study, horses use a wide range of facial expressions as social cues – much like humans do. Researchers have identified 17 discrete movements, many of which are also used by humans, despite obvious differences in facial structure. They published their findings Wednesday in the journal PLOS ONE.

It’s no secret that human emotion is inextricably tied to facial expression. But facial expression in the animal world is significantly understudied, says Karen McComb, lead author and professor of animal cognition at the University of Sussex. Until recently, systematic studies on the subject were few and far between – and those tended to focus on non-human primates.

Because equine facial structure is so different than primate facial structure, scientists had overlooked horses as candidates for this sort of communication. But as highly visual and socially complex animals, they are actually well suited for facial expression study, says Dr. McComb.

"They have long-term relationships within their own social group or band," she says. "Neighboring bands also come into contact as they move and feed.... Social living and interacting with multiple individuals, both within and outside the immediate social group, is likely to have selected for enhanced social communication – and we think that facial expression is an important part of this.”

By developing the Equine Facial Action Coding System (EquiFACS), researchers could demonstrate the connection between facial movement and communication. They found that horses were capable of 17 distinct “action units,” or facial movements. Humans are capable of 27. Both horses and humans modify their facial expressions roughly the same way – by using facial muscles to contort the nostrils, lips, and eyes. Horses also express themselves through their ear position, like cats and dogs.

But while McComb and her colleagues were able to map out the expressive capabilities of horses, they have yet to determine how those expressions are used.

"Our work shows that horse facial expressions are quite complex," McComb says. "The next step is to relate particular facial movements and configurations to specific contexts – positive versus negative."

She added, "We’re working on what constitutes the horse 'smile.' "

By linking expressions to different contexts, researchers hope to determine whether those expressions indicate positive or negative emotional states. For those concerned with horse welfare, that would be a major breakthrough.

"Animal welfare is increasingly seen as being as much about the presence of positive emotions as the absence of negative ones," McComb says. "EquiFACS should put us in a position to chart what the positive expressions actually are – as well as making us better at identifying the negative ones."

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