Can Ponies Distinguish Human Facial Expressions?

Most humans are good at giving someone a wide berth if they approach with a furrowed brow, but how good are horses at interpreting our expressions? Dr. Katrina Merkies, researcher and associate professor at the University of Guelph, and her team found out in a study involving 20 lesson ponies and some talented actors. 

There has been past research conducted with flash cards, but this is the first study to document the response of equines that were shown happy, sad, angry, and neutral facial expressions in person. 

“In terms of behaviour generally, the right brain processes emotions and particularly negative stimuli,” explains Merkies, “whereas the left brain is more related to social interactions and learned behaviour.” 

Horses see things on their left side with their left eye, and things on their right side with their right eye, and unlike humans there’s very little fusion in their optic nerves, and they don’t really have a lot of binocular vision. 

The optic nerve brings information from the eye to the brain and crosses from the left eye to the right side of the brain, and from the right eye to the left side of the brain. In horses, because their eyes are located on the sides of their head with largely monocular vision, it is easy to discern that what they see with their left eye is processed in the right brain and vice versa.