Are We Smart Enough to Know How Smart Animals Are?(49)

Books and articles commonly state that one of the central issues of evolutionary cognition is to find out what sets us apart. Entire conferences have been organized around the human essence, asking “What makes us human?” But is this truly the most fundamental question of our field? I beg to differ. In and of itself, it seems an intellectual dead end. Why would it be any more critical than knowing what sets cockatoos or beluga whales apart? I am reminded of one of Darwin’s random musings: “He who understands baboon would do more towards metaphysics than Locke.”58 Every single species has profound insights to offer, given that its cognition is the product of the same forces that shaped ours. Imagine a medical textbook that declared that its discipline’s central issue is to find out what is unique about the human body. We would roll our eyes, because even though this question is mildly intriguing, medicine faces far more basic issues related to the functioning of hearts, livers, cells, neural synapses, hormones, and genes.

Science seeks to understand not the rat liver or the human liver but the liver, period. All organs and processes are a great deal older than our species, having evolved over millions of years with a few modifications specific to each organism. Evolution always works like this. Why would cognition be any different? Our first task is to find out how cognition in general operates, which elements it requires to function, and how these elements are attuned to a species’s sensory systems and ecology. We want a unitary theory that covers all the various cognitions found in nature. To create space for this project, I recommend placing a moratorium on human uniqueness claims. Given their miserable track record, it is time to rein them in for a few decades. This will allow us to develop a more comprehensive framework. One day years from now, we may then return to our species’s particular case armed with new concepts that allow a better picture of what is special—and what not—about the human mind.

One aspect we might focus on during this moratorium is an alternative to overly cerebral approaches. I have already mentioned that perspective taking is likely tied to bodies, and the same applies to imitation. After all, imitation requires that another individual’s body movements are perceived and translated into one’s own body movements. Mirror neurons (special neurons in the motor cortex that map another’s actions onto one’s own bodily representations in the brain) are often thought to mediate this process, and it is good to realize that those neurons were discovered not in humans but in macaques. Even though the precise connection remains a point of debate, imitation likely is a bodily process facilitated by social closeness.

This view is quite different from the cerebral one according to which it all depends on the understanding of cause-effect relations and goals. Thanks to an ingenious experiment by the British primatologist Lydia Hopper, we know which view is correct. Hopper presented chimps with a so-called ghost box controlled by fishing lines. The box magically opened and closed by itself, producing rewards. If technical insight were all that mattered, watching such a box should suffice, as it shows all the necessary actions and consequences. But in fact, letting chimps watch the ghost box ad nauseam taught them nothing. Only after seeing an actual chimp operate the same box, did they learn how to get the rewards.59 Thus for imitation to occur, apes need to connect to a moving body, preferably one of their own species. Technical understanding is not the key.60

To find out how bodies interact with cognition, we have incredibly rich material to work with. Adding animals to the mix is bound to stimulate the up-and-coming field of “embodied cognition,” which postulates that cognition reflects the body’s interactions with the world. Until now, this field has been rather human-focused while failing to take advantage of the fact that the human body is only one of many.

Consider the elephant. It combines a very different body with the brainpower to achieve high cognition. What is the largest land mammal doing with three times as many neurons as our own species? One may downplay this number, arguing that it has to be corrected for body mass, but such corrections are more suited to brain weight than to number of neurons. In fact, it has been proposed that absolute neuron count, regardless of brain or body size, best predicts a species’ mental powers.61 If so, we’d better pay close attention to a species that has vastly more neurons than we do. Since most of these neurons reside in the elephant’s cerebellum, some feel they carry less weight, the assumption being that only the prefrontal cortex matters. But why take the way our brain is organized as the measure of all things and look down on subcortical areas?62 For one thing, we know that during Hominoid evolution, our cerebellum expanded even more than our neocortex. This suggests that for our species, too, the cerebellum is critically important.63 It is now up to us to find out how the remarkable neuron count of the elephant brain serves its intelligence.

The trunk, or proboscis, is an extraordinarily sensitive smelling, grasping, and feeling organ said to contain forty thousand muscles coordinated by a unique proboscis nerve that runs along its full length. The trunk has two sensitive “fingers” at the tip, with which it can pick up items as small as a blade of grass, but the trunk also allows the animal to suck up eight liters of water or flip over an annoying hippo. True, the cognition associated with this appendage is specialized, but who knows how much of our own cognition is tied to the specifics of our bodies, such as our hands? Would we have evolved the same technical skills and intelligence without these supremely versatile appendages? Some theories of language evolution postulate its origin in manual gestures as well as in neural structures for the throwing of stones and spears.64 In the same way that humans have a “handy” intelligence, which we share with other primates, elephants may have a “trunky” one.