Humans have been living and working with horses for more than 5,000 years, since the first domesticated equines in northern Kazakhstan. Hands could not have built modern civilization without the help of hooves—to haul ploughs, pull carriages, march soldiers into battle, and carry messages of love and war across hundreds of otherwise-insurmountable miles.
An unlikely pairing of wily predator and one-ton prey, humans and horses have managed to successfully communicate across the species barrier because we share a language: emotion.
Experienced riders and handlers can learn to read the subtle moods of individual horses according to wisdom passed down from one horseman to the next, but also from years of trial-and-error. I suffered many bruised toes and nipped fingers before I could detect a curious swivel of the ears, irritated flick of the tail, or concerned crinkle above an eye.
Horses can read human emotions, too, often in uncannily accurate ways; alerting us to our nervousness or sadness sometimes before we’ve even consciously registered it. As Herman Melville wrote in Redburn, "No philosophers so thoroughly comprehend us as dogs and horses."
The equine ability to read human emotion through sound and touch is exquisite. But horses can also read the expression on a person’s face—as a Biology Letters paper earlier this month confirmed for the first time. This sophisticated capacity has only ever previously been demonstrated in dogs..
The horses tended to look at angry faces out of their left eye, engaging the part of the brain where fear-provoking stimuli are processed. A University of Sussex research team, led by Amy Smith alongside the veteran animal-behavior scientist Karen McComb, showed a group of 28 horses large photographs of man’s face making either a positive (smiling) or negative (angry, brows furrowed) emotional expression. The results showed that horses were able to automatically distinguish between the two expressions, and what they meant.
The horses tended to look at the angry faces out of their left eye—a response well documented in horses and dogs indicating that an animal is engaging the right hemisphere of its brain where novel and fear-provoking stimuli are processed. The horses’ heart rates also rose more quickly when they were presented with the angry face. Being able to tell a smiling handler from an angry one is a useful skill for a domestic horse—being approached by a frown rarely results in happy consequences.
While these latest findings probably come as no surprise to those who work with horses on a daily basis, they are one more piece in the increasingly complex picture of the emotional language humans share with other species. Horses’ ability to read faces perhaps also refines the explanation for horses’ therapeutic and even spiritual effects on humans, documented in our art and stories since the first etchings on cave walls... It’s increasingly clear that horses are highly emotionally attuned—and not all that different from the animals they carry on their backs.