Horses are able to recognize their caregivers by looking at a photograph of their face, even some they haven’t seen in months, researchers in France have found.
While horses readily recognize their caregivers in the flesh, the findings of a new study indicate that they appear to grasp photographs as being symbolic representations of those familiar individuals.
In humans, the memory for faces can be remarkable. People recognize faces they have not seen for more than 50 years. However, the degree to which horses are capable of remembering the identity of people they have spent time with is unknown.
“Considering the life-span of a horse of between 25 and 30 years, and particularly regarding previous studies on the horse’s ability to memorize information, it would be reasonable to think that a horse could remember information for a period of several months,” the researchers reported in the journal Scientific Reports.
That assumption proved correct. The study, led by Léa Lansade of the French National Research Institute for Agriculture, Food and Environment, showed that horses can remember a keeper’s face six months after having seen the person.
The study involved 11 three-year-old Welsh mares who were trained to use a touchscreen in a facial recognition test developed by the researchers.
The horses approached the screen voluntarily and launched the test with a touch of their nose.
In the training phase, two photographs of faces were presented at the same time.
All the faces were initially unfamiliar, but four were repeated with the aim of becoming familiar to the horses. Whenever the horses selected one of these familiar faces, they received a reward.
The unfamiliar faces which appeared alongside them were rotated from a much larger pool and never repeated.
All images were those of women.
The horses rapidly understood the rules of the game, according to the researchers.
After the training phase, the faces of the horses’ keepers were presented opposite the faces of strangers to test whether the horses could identify their caregivers. A reward was given whichever face was touched to avoid any possible learning effect.
The study team found that the horses touched the faces of keepers significantly more than chance, whether it was their current keeper or one they had not seen for six months. They readily reached the success criteria of 75%.
“Overall, these results show that horses have advanced human face-recognition abilities and a long-term memory of those human faces,” the researchers concluded.
As the researchers point out, would human beings be able to point out animals they saw months ago by simply looking at a picture?
The authors say the findings indicate sophisticated socio-cognitive skills, which should be taken into account in our everyday interactions with the animal.
The results also raise new ethical issues around human behaviour towards equines, particularly in terms of breeding, and the relationship between breeders and their animals.
“This study implies three main results regarding the cognitive abilities of horses,” the researchers said.
“Firstly, our results suggest that horses are able to spontaneously understand the representational nature of two-dimensional images.” This, they suggest, is an interesting skill on its own.
Photographs, they point out, represent only a small part of the information concerning reality. No recognition is possible through odors, behavior or voice, and there is also a loss of visual information such as depth, perspective or movement.
“Thus, some species, such as dogs, have difficulties recognizing photographs of faces and particularly when only the central part is visible, whereas they are quite capable of recognizing faces in real-life conditions.
“This does not appear to be the case for horses.
“The horses in our study did not appear to have any difficulties adjusting between a real person and a photograph of their face, without prior learning.
“Secondly, this shows that the horses had a good ability to identify faces.
“Finally, probably the most noteworthy finding of this study is the information provided on horses’ long-term memory capacities.
“The fact that the horses recognized the photograph of a person they had not seen for six months shows that they have a good memory for faces, a fact that was unknown until now.”
Previous studies have shown that horses can remember learning tasks accomplished about two years previously, with no decrease in performance. Another study, conducted on only three horses, showed that they recalled correctly complex problem-solving strategies seven years later.
“Regarding the more specific human-animal relationship, horses could remember interactions they had had with human beings five months, or even a year previously.
“The present study shows that beyond remembering what they have learned or the interactions they have had with humans, horses also have an excellent memory of people and particularly of their faces.”
Lansade and her colleagues say their study opens several other avenues to be investigated.
For example, how would the horses have reacted if they had a difficult relationship with the person whose familiar face was shown to them?
“In that case, we might expect avoidance behavior or anxiety. It would be interesting to test this possibility in the future.”
It would also be interesting, they said, to discover if horses are able to recognize different portraits of the same person, showing different profiles or hairstyles, and whether certain images were more likely to be chosen correctly.
The study team comprised Lansade, Violaine Colson, Céline Parias, Miléna Trösch, Fabrice Reigner and Ludovic Calandreau.
Lansade, L., Colson, V., Parias, C. et al. Female horses spontaneously identify a photograph of their keeper, last seen six months previously. Sci Rep 10, 6302 (2020). https://doi.org/10.1038/s41598-020-62940-w