If we ask people to list the smartest animals, they will name some common suspects. Chimpanzees, dolphins, and elephants are often mentioned, as well as crows, dogs, and occasionally pigs. Horses do not usually appear on this list.
So it may come as a surprise that horses possess unusual ability, widely considered an indicator of self-awareness. In a recent study, researchers found that horses can recognize their reflections in mirrors.
Animals who look at themselves in a mirror for the first time tend to respond socially: they act as if their reflection were another animal. After a while, this social response tends to disappear. Some animals lose interest at that moment, but others continue to explore the mirror and investigate how they can make the reflection move using their own body.
Once the animals have stopped responding socially, scientists check their understanding using the “mark test.” The animal is marked in a place that you can only see in the mirror, perhaps on the forehead or on the ear. The scientists then observe whether the animal spends more time touching this part of the body in front of the mirror when it is marked than when it is not. Doing so suggests that the animal recognizes its reflection.
This test was first used to demonstrate self-recognition in chimpanzees in 1970, and since then scientists have used versions of the test to search for it in many other species. The results suggest that it is rare. Among non-primates, only a few animals have passed the mark test, including four bottlenose dolphins, two Eurasian magpies and an Asian elephant.
But a new study by researchers in Italy has found evidence of self-recognition in horses. Interestingly, the results suggest that this ability is not limited to a few intelligent individuals. Although caution must be exercised when generalizing from a single study, this suggests that self-recognition could exist in horses as a species.
The mirror test
In the studio, a large mirror was placed on a horse training arena. Once the horses became accustomed to the mirror and stopped responding socially, the researchers used the mark test to seek self-recognition, comparing the horses’ behavior under two conditions. In one condition, the researchers drew a cross shape on both cheeks with a colorless ultrasound gel. In the other, they were marked in the same way but with a colored ultrasound gel.
The important question was whether horses would be more interested in visible marks than invisible ones. So it was. The horses spent about five times as long scratching their faces in front of the mirror when they were visibly marked.
The researchers concluded that they saw the marks in the mirror, understood that those marks were on their own faces, and tried to remove them. They recognized his reflexes.
Aware of their own body
The brand test is often described as a test of self-awareness. But it is debatable whether that is true and depends on what we mean by self-consciousness, a complicated philosophical question.
When we say that a person is aware of himself, we usually mean that he has a special vision of his own mind. Maybe you know what you really want or are aware of your personality flaws.
Some researchers have argued that self-recognition involves having a concept of oneself as a psychological agent with a mind. But that is not a popular opinion, because recognizing the reflection does not imply thinking about the state of mind.
Self-recognition seems to have more to do with being aware of our bodies. Of course, even very simple animals are aware of their own bodies, even those that fail the mark test. But, as I have argued in my own research, there are different ways of being aware of your own body.
Some of our senses provide us with a special awareness of our body “from within.” For example, something called proprioception gives us information about the position of our body. When proprioception tells us that we are stooped, we do not have to find out who is stooped, but we know immediately that it is us.
But mirrors allow us to become aware of our body “from the outside.” When we see a body in the mirror, it is not obvious that this body is ours: we have to discover it. I have argued that taking this external, objective perspective on ourselves and our bodies is another kind of self-awareness.
Although this new study does not show that horses can reflect on their own minds, it does place them in the small group of animals that can think objectively about their own bodies. Perhaps it is time to review our assumptions about horses. They may be a lot smarter than we think.