Some horses recognise their reflections in mirrors, says expert

Credit: Adobe Stock
Credit: Adobe Stock

Some animals have a well-developed self-awareness, but it is difficult for us to measure it using a simple mirror test. However, during research on horses, some of them behaved in a way that suggested that they recognised themselves in a mirror, says Dr. Tomasz Smoleń from the Department of Cognitive Science at the Jagiellonian University.

PAP: You investigated self-awareness of horses. Where did this idea come from?

Dr. Tomasz Smoleń, Jagiellonian University: Our research is part of a large trend, one that is interesting both for practical reasons, but also due to the desire to deepen knowledge about the world in which animals are aware at some level. Awareness is not a binary trait, in the sense that it exists only at the human level or it does not exist at all, as in some simple insects. There is a continuum between these insects to humans, and at each stage you can find interesting elements of this self-awareness.

PAP: What is the awareness we are talking about?

T.S.: We are most interested in the highest level of awareness that we see in people, where we can look at ourselves from the outside and see ourselves as active actors in a larger structure - for example a social one, analyse our actions and their potential consequences. Most animals are not capable of this, at least we don't think so, but some animals can surprise us when it comes to developing self-awareness - especially birds and mammals.

PAP: The biggest problem is probably the methodology, because it is impossible to assess the behaviour of, for example, a chimpanzee, a dolphin or a horse in the same way?

T.S.: The only test that has been invented for this purpose and is widely used is the mirror test. It consists of showing an animal a mirror and if the animal is able to recognize itself in this reflection - that it is a reflection of itself and not some other representative of this species - then we can draw the conclusion that the animal is able to adopt an external perspective in relation to itself, which would indicate self-awareness.

PAP: The problem is that different animals prefer different senses to perceive reality.

T.S.: Even at an intuitive level, we can agree that some animals have developed self-awareness, but it is difficult for us to measure it using this simple test. If only for the reason that some, such as chimpanzees, rely mainly on sight, and in the case of, for example, dolphins or elephants, this is not so obvious. The same goes for horses. The research on horses was undertaken by a master's student from our department, Ida Ilmer, who decided to overcome all the obstacles associated with the mirror test.

PAP: And what came out of it?

T.S.: The results are interesting. They confirmed the hypothesis - the presence of a mirror changed the behaviour of a large number of horses, in a way that suggested that they recognised themselves in the mirror. However, we did not observe this behaviour in all horses, only in about half of the tested animals.

PAP: And what does a horse that recognises itself look like? How can you tell if it knows it is seeing its own reflection?

T.S.: Well, that is where the problem lies, namely the methodology. When chimpanzees, or at least some species of chimpanzees, were studied, it was done by drawing a small spot with odourless paint on the subject's eyebrow or in another place it could not see without a mirror. Later, the animal was subjected to a mirror test: it could see itself in a mirror. And if it saw a spot in the reflection and reached for the mirror, it meant that it saw it on another animal's face. However, if it reached up to its own eyebrow, it meant that it recognized itself in the mirror reflection.

PAP: How did you modify this test to suit horses?

T.S.: We solved it by attaching a carrot to the lower part of the horse's front leg. These animals are very fond of this vegetable, and they also have a specific field of vision: they cannot see their legs when standing. So if they reached for a carrot when placed in front of a mirror, it meant that they recognized themselves in the reflection, saw something that caught their attention - they would reached for their leg and munch on the treat.

PAP: They could have simply sniffed it out.

T.S.: We took that into account. While attaching the carrot, the horses were given a lick that emitted a scent strong enough to mask the smell of the treat.

PAP: And what happened next?

T.S. Some horses, unfortunately, failed the test and could not find the carrot, but at least some of them recognised themselves.

PAP: Did those that did not recognise themselves in the mirror reach for a carrot in the mirror reflection?

T.S.: No. It is not in the nature of these animals. Even if they identified the delicacy in the mirror image, if they didn’t see themselves but another horse, they preferred to ignore it all, because in their social relations and hierarchy there is no possibility for a horse to reach under the nose of another representative of the species and steal food. This would involve a major conflict, which these animals do not like.

PAP: What were the proportions of the animals that found a carrot reflected in the mirror and those that did not find it and walked away from the mirror?

T.S.: It was half and half, but we tried to take into account other traits of the horses that could have an impact, e.g. gender or body type. Among other things, we hypothesized that warm-blooded horses would pass this test better than cold-blooded horses or ponies. This may be because warm-blooded horses have a different behavioural pattern: they are more active and explore more. We also thought that the mares were doing better than the geldings, but I can't say for sure because the sample size was too small to draw a clear conclusion.

PAP: Do you plan to continue this research?

T.S.: We would love to, but to make it happen we need funding, which we might be able to secure. So far, we have conducted research on our own, with the help of friendly stables, but to obtain more reliable data, we would need a larger sample. However, we have already planned a continuation of this research: Ida Ilmer is currently conducting research on the efficiency of working memory in horses. We are also planning to undertake imaging of the brain of these animals using an electroencephalograph in collaboration with Professor Magdalena Senderecka and Professor Mateusz Hohole, and this is not an easy task.

PAP: What conclusions can be drawn from this type of research around the world?

T.S.: Research on horses is carried out sporadically because it is very difficult and, to tell the truth, we have not been able to establish cooperation with any centre that has conducted such research. We are pioneers, we are still developing research tools.

PAP: If it is confirmed that horses are self-aware, what practical significance might the results of your research have?

T.S.: This may have an impact on research on horses: how it should be conducted. And how horses should be treated when it comes to their breeding and husbandry.

Fortunately, in the case of horses, we are in a better situation than in the case of other animals - horses are not used in biochemical or medical research on a large scale. In addition, the welfare of horses is something that is important for many people who care for them, there is an awareness among breeders and among horse riders that these animals deserve as much welfare as can be provided to them.

And the most important thing that emerges from our research is that these wonderful animals, which, as I understand it, have high self-awareness, should not be kept alone. They are gregarious creatures and for their well-being they should live at least in pairs. If they are kept alone, they suffer greatly. (PAP)

Mira Suchodolska

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