Of horses and humans, science, and anthropomorphism.
Dear Horse Lovers, this is quite an unusual post for me, who is normally a bit on the “harmony seeking” side. But I feel compelled to speak out on behalf of our four-legged friends. But let’s begin at the beginning: The so-called prefrontal cortex is a structure in the mammalian brain that is thought to be of fundamental importance for behavioral control and problem solving. This structure has so far been demonstrated in all mammals studied regarding this research question. However, the rumor persisted that horses lack this structure. An assumption that was not based on scientific facts/results, but merely on an incorrect interpretation of the flight behavior of horses. After finally accepting, that the horse brain, like all mammal brains, also includes a structure called the prefrontal cortex, a new myth is now circulating through social media, namely that this structure is “underdeveloped” in horses compared to the human brain. What’s wrong with this notion? The word "underdeveloped", which contains a judgement and places the human primate in the position of a “gold standard”. Therefore, this statement is no major improvement on the assertion that horses have no prefrontal cortex at all, it reflects the same anthropomorphistic attitude.
Interestingly enough, in behavioral studies, horses show absolutely highly developed behavior that, according to everything we know about the functioning of the prefrontal cortex, could not be solved without such a structure in the brain (Brucks, Härterich, König von Borstel, 2022). This type of behavior or task is called "delay of gratification" (e.g. Latzman & Taglialatela, Hopkins, 2015). Deferred or delayed gratification involves the ability to postpone an immediate gain in favor of a later, even greater reward, a type of experiment that allows conclusions to be drawn about impulse control. HUMAN CHILDREN ARE NOT CAPABLE OF CONSISTENTLY SOLVING THIS TASK UNTIL THEY REACH PRESCHOOL AGE (!). The ability to postpone rewards is considered a sign of high intelligence and fundamental to the ability to plan and make decisions. And let's be honest, if horses didn't have this ability, horse training would be almost impossible. We would never get past the first green grass in spring, to name just one example.
Denying the existence of a prefrontal cortex in the horse reveals a substantial lack of knowledge about evolution, phylogeny, and the mammalian brain; the notion that the horses’ prefrontal cortex is “underdeveloped” unmasks a profound anthropomorphic attitude, that is the opposite of what the purpose of equine bioscience and equitation science is: namely to provide unbiased and nonjudgmental knowledge about our four-legged friends. If anthropocentrism wasn’t at the core of most of the misunderstandings between horses and humans and one of the core issues of unethical training, this kind of anthropomorphism judging other species from a naïve human perspective would almost be funny. However, it is not.
The “scale” against which a structure & function of the “construction” of a species must be measured is its living environment, its habitat, and the demands associated with the way of living of the particular species in question. Giraffes have a long neck, because they feed of trees, the representation of the neck in their brains will reflect the enormous dimension of their neck. The hippopotamus has a blobby body without a neck because it needs to float. That is his way of living, and the long neck of a giraffe would only be useful if the hippopotamus needed a scope like a submarine. The mole has almost no eyes, because they are not necessary for his lifestyle and the visual cortex of the mole brain will reflect that. The horse, as a flight animal, has the largest eyes of all land-living animals with an almost 380 degrees round view, because he needs to detect a predator as early as possible and then needs to run immediately. The mammal brain, as principally standardized as the mammal body, is as variable as and adaptable as the mammal body and will likewise adjust to the needs of the species in quest according to its habitat and way of living. Anatomy as well as neuroanatomy follow function and that is what has made mammals so successful in evolution that they have filled almost every ecological niche thinkable.
Thus, the appropriate scale to measure the capabilities of a species against is the challenges of its habitat and that is the only legitimate measure that gives us an UNDERSTANDING as opposed to judgement. Regarding the prefrontal cortex the human primate (or primates generally) is the exception to the rule in the animal realm, with his hypertrophic prefrontal cortex that allows him to control fear. Because of this evolutionary development as a social hunter, primates are e.g. capable to wage war against each other. If the horse had a human-like hypertrophic prefrontal cortex to inhibit his fight-flight response, humans would never have had a chance to exercise anthropomorphism towards horses, because horses would long be extinct, and no human would have ever met a horse. The mammalian body as well as the mammalian brain develop according to the requirements of the habitat. ALL living beings who are still around possess the perfect brains for the challenges of their living environment. Otherwise, they would not be around.
Much would be achieved to make this world a better place for our four-legged friends, if we human primates would use our hypertrophic, overdeveloped prefrontal cortex for a little bit of reflection over ourselves. If science is to help us to be better equestrians, the first requirement to us humans in interpreting the results of studies is to refrain from anthropomorphism, to ban an attitude that places the human primate above all other living beings and measures all other species against us most imperfect humans. From the perspective of most other animals of this world, our human senses are so underdeveloped, that they are almost dysfunctional, and they would probably wonder how we survive with such fundamental deficiencies. Let's be honest, as underdeveloped as we vulnerable, naked little humans are sensory-wise, we had no choice but to plan well and develop a huge prefrontal cortex to do so, otherwise we would have disappeared long ago 😉
The anthropomorphic perspective includes the expectation that horses behave like "little" humanoids and then consistently condemns them for their failure and inadequacy to behave human-like. We would gain a lot if we asked ourselves how the behavior of our four-legged companions helps them to cope with the challenges of their original habitat, the world they lived in before they were domesticated and had to cope with the expectations of us humans. This shift in perspective can be a first small exercise in our journey to better understand our four-legged companions. My heart tells me that those who follow this page are on this journey with me <3
Ok, enough ranting. If you want to refresh your knowledge about the question of whether horses have a prefrontal cortex and what it is good for, just revisit the Blog about this topic:
References:
Brucks D, Härterich A and König von Borstel U (2022) Horses wait for more and better rewards in a delay of gratification paradigm. Front. Psychol. 13:954472. doi: 10.3389/fpsyg.2022.954472
Latzman, J.P. Taglialatela, W.D. Hopkins. Delay of gratification is associated with white matter connectivity in the dorsal prefrontal cortex: a diffusion tensor imaging study in chimpanzees (Pan troglodytes). Proceedings of the Royal Society B: Biological Sciences, 2015; 282 (1809): 20150764 DOI: 10.1098/rspb.2015.0764
Picture credits: Generated with AI, Mach 23 2024 at 1.46 pm