Humans have long formed bonds with horses, but a new study may show the species is even more emotionally connected to us than we thought.
The study, performed by psychologists at the University of Sussex, found horses have the ability to distinguish between positive and negative human emotions. Researchers showed horses life-size images of humans either smiling or baring their teeth in anger. As they wrote in their findings in the journal Biology Letters, the horses were able to distinguish between the two, reacting to the angry photos by turning their heads to look at them with the left eye. As the Guardian explains, viewing something through the left eye allows it to be interpreted in the right hemisphere of the brain, where threatening stimuli are processed.
“What’s really interesting about this research is that it shows horses have the ability to read emotions across the species barrier,” said a doctoral student at the university. “We have known for a long time that horses are a socially sophisticated species but this is the first time we have seen that they can distinguish between positive and negative human facial expressions.”
Sussex researchers had previously shown that horses have distinct facial expressions of their own that are not dissimilar to human expressions, including smiling and widening the eyes in fear.