Science: Both horses and dogs understand our facial expressions

July 16, 2018

We humans can be pretty good at bonding with animals. Horses and dogs in particular are two of the species we have formed the closest ties with — we work with them, we play with them, we live with them.

Why is that? Well, science shows us that dogs and horses, unlike many other species, are likely able to understand the facial expressions we make around them, giving them insight into our moods and emotions.


Research shows that even if a horse is observing a total stranger, the animal is still able to interpret their facial expressions. A recent study used something called the “expectancy violation method,” a technique used to measure the cognitive development of babies, to figure out if they could do this or not.

This involved showing the horses a photo of a happy face or an angry face alongside a recording of a praising or scolding human voice. The voice was either congruent with the photo (both happy) or incongruent (happy and angry, or vice versa).

In the study, the horses were shown to respond 1.6 to 2 times faster, and to stare at the photo 1.4 times longer, in incongruent conditions. This suggests that the horses experienced an expectancy violation, or that horses combine facial expressions and voices to form their understanding of the emotional state of the human. When the faces and voices didn’t match up, the horses spent a longer time processing.


Dogs not only understand some human expressions — they react to them in kind with gestures of their own.

One study found that after realizing someone was angry, fearful or happy, dogs tended to turn their heads to the left. They turn their heads to the right when noticing surprise on a human face. And their heart rates bump up when they see someone who is having a “bad day,” the researchers said. This study was also conducted using photos to gauge reactions.

The researchers say that, since dogs have lived in such close contact with humans for so long, they’ve likely developed the specific skills that let them interact efficiently with people. And not only is it the face — studies suggest that dogs can read emotional cues in voice, body odor and posture as well.