When shown pictures of an unfamiliar human with a threatening facial expression, horses become stressed and view the image using their left eye. While similar behaviors have been documented in domestic cats and dogs, this is the first time researchers have found horses can interpret the different emotions of their handlers, too.
Researchers found domestic dogs can tell the difference between a threatening and pleasant facial expression by gazing into one's eyes. This is similar to a human's social gazing behavior.
Dogs can rapidly mimic each other's expressions, just like humans and some primates.
Researchers have tallied up a list of horse expressions for various social interactions, and note that the competition isn't looking good for dogs.