Horses can decipher facial expressions, distinguishing between positive and negative emotions, a recent study has revealed.
The surprising findings were presented on Wednesday, February 10, in the journal Biology Letters, following unprecedented research conducted by experts at the University of Sussex, in the United Kingdom.
The experiment focused on a group of 28 horses selected from 5 boarding stables and riding schools across Surrey and Sussex during a period spanning from April 2014 to February 2015.
The equine creatures didn’t receive any instruction prior to the trial, because study authors wanted to investigate instinctive reactions, that hadn’t been modeled or influenced by trainers beforehand.
The human volunteers who took part in the study also had little information to rely on, so that their assessments could be as objective and accurate as possible.
What researchers required the human participants to do was to expose the horses to large, high definition photographs depicting various emotions, and to record the animals’ subsequent reactions.
All the images had the same male protagonist, whose face was completely unfamiliar to the equine subjects.
In some of the photos, the man was looking happy and approachable, as evidenced by his warm grin; in the rest of the visual materials he appeared to be menacing and angry, as suggested by his frown and by his bared teeth.
Volunteers jotted down observations and notes detailing the horses’ reactions to the images, and at the same time researchers monitored the animals’ heart rate, in order to identify any potential changes.
At the end of the experiment, all this data was aggregated and analyzed, and it soon became obvious that all the horses had had similar manifestations when confronted with specific facial expressions, adopting the same type of behavior after identifying a certain emotion.
More precisely, upon encountering an ominous countenance, the horses’ heart rates escalated significantly, and other commonly encountered stress symptoms also became more prominent. In addition, the animals tilted their heads, so that they could gaze at the photo with their left eye.
As study authors explain, this reaction was extremely telling, given the fact that information captured by the left eye is normally decoded and interpreted in the right hemisphere of the brain, which is exactly the region where threatening stimuli are detected and processed.
This suggests that horses were able to identify emotions and categorize them correctly, in order to skillfully adapt their own behavior to that of their human counterparts.
Reactions were much stronger when it came to negative emotions displayed by the man in the photograph, than when it came to positive feelings, probably because recognizing dangerous situations is much more vital to survival than taking advantage of favorable circumstances.
Prior research had shown that dogs also look at the forbidding faces of their masters with their left eye, distinguishing menacing facial expressions and reacting accordingly.
Similarly, sheep had been proven to be soothed simply when seeing the picture of another ewe, and it had also been determined that they can recognize and recall up to 10 human beings and around 50 sheep for even 2 years.
Horses however hadn’t been studied so thoroughly, even though they had been shown to have a greater variety of facial gestures than dogs or chimpanzees, being surpassed solely by cats in terms of expressiveness.
That is why these new findings are quite ground-breaking, indicating that the ability to correctly process facial cues and respond to them appropriately may be more common in the animal kingdom than we might have guessed.
In fact, it appears that many creatures such as horses or dogs can reliably identify emotions experienced not just by members of the same species, but also by human beings.
This may be because as domestic pets, these animals have come to rely on human beings as providers of food, care and shelter. As a result, they’ve had to learn to read human emotions in order to adjust their behavior based on the wishes and caprices of their owners.
According to co-author Karen McComb, it may be that deciphering facial expressions is a skill that horses and dogs have developed across generations, until it became innate and instinctual.
Alternatively, this talent may simply be the result of each animal’s own interactions with human beings, being therefore based on experience and not on ancestral knowledge.
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