Are We Smart Enough to Know How Smart Animals Are?

by Frans de Waal

sensory input into knowledge about the environment and the flexible application of this knowledge. While the term cognition refers to the process of doing this, intelligence refers more to the ability to do it successfully.

Cognitive evolution is marked by many peaks of specialization. The ecology of each species is key.

The credo of experimental science remains that an absence of evidence is not evidence of absence.

Species-typical behavior is as recognizable and measurable as any physical trait. Given their invariant structure and meaning, human facial expressions are another good example. The reason we now have software that reliably recognizes human expressions is that all members of our species contract the same facial muscles under similar emotional circumstances.

Insofar as behavior patterns are innate, Lorenz argued, they must be subject to the same rules of natural selection as physical traits and be traceable from species to species across the phylogenetic tree. This is as true for the mouth brooding of certain fish as it is for primate facial expressions.

There is even a joke about its complete reliance on external cues, in which one behaviorist asks another after lovemaking: “That was great for you. How was it for me?”

For those who disparage anecdotes altogether, it is good to keep in mind that almost all interesting work on animal behavior has begun with a description of a striking or puzzling event. Anecdotes hint at what is possible and challenge our thinking.

But making things harder, Call would sometimes shake only the empty cup, which made no noise. In this case, the apes would still pick the other one, thus operating on the basis of exclusion. From the absence of sound, they guessed where the grapes must be. Perhaps we are not impressed by this either, as we take such inferences for granted, but it is not all that obvious. Dogs, for example, flunk this task. Apes are special in that they seek logical connections based on how they believe the world works.

Goodall described how Madame Bee, a wild chimpanzee, had become too old and weak to climb into fruiting trees. She would patiently wait at the bottom for her daughter to carry down fruits, upon which the two of them would contentedly munch together.5 In such cases, too, apes grasp a problem and come up with a fresh solution, but the striking part here is that they perceive another ape’s problem.

Cognition relates to the kind of information an organism gathers and how it processes and applies this information.

The role of learning is obvious, but what is special about cognition is that it puts learning in its proper place. Learning is a mere tool. It allows animals to collect information in a world that, like the Internet, contains a staggering amount of it. It is easy to drown in the information swamp. An organism’s cognition narrows down the information flow and makes it learn those specific contingencies that it needs to know given its natural history.

(Both jackdaws and crows are corvids, a brainy bird family that also includes jays, magpies, and ravens.)

Evolutionary science distinguishes between homology (the traits of two species derive from a common ancestor) and analogy (similar traits evolved independently in two species). The human hand is homologous with the bat’s wing since both derive from the vertebrate forelimb, as is recognizable by the shared arm bones and five phalanges. The wings of insects, on the other hand, are analogous to those of bats. As products of convergent evolution, they serve the same function but have a different origin.

As soon as an ape sees something attractive yet out of reach, he starts to cast about for a bodily extension. An apple floats in the moat around the zoo island: the ape takes one glance at the fruit before racing around in search of a suitable stick or a few stones that he can throw behind it so that it will float toward him. He distances himself from his goal in order to reach it—an illogical thing to do—while carrying a search image of what tool might work best. He is in a hurry, because if he doesn’t return fast enough, someone else will beat him to the prize. If, on the other hand, his goal is to eat fresh green leaves from a tree, the required tool is quite different: something sturdy to climb on.

The arrival of corvids on the scene illustrates how discoveries of mental life ripple across the animal kingdom, a process best summarized by what I’ll call my cognitive ripple rule: Every cognitive capacity that we discover is going to be older and more widespread than initially thought. This is rapidly becoming one of the best-supported tenets of evolutionary cognition.

Now that I think of it, my distrust of language goes even deeper, because I am also unconvinced of its role in the thinking process. I am not sure that I think in words, and I never seem to hear any inner voices. This caused a bit of an embarrassment once at a meeting about the evolution of conscience, when fellow scholars kept referring to an inner voice that tells us what is right and wrong. I am sorry, I said, but I never hear such voices. Am I a man without a conscience, or do I—as the American animal expert Temple Grandin once famously said about herself—think in pictures?

It is now widely accepted that, even though language assists human thinking by providing categories and concepts, it is not the stuff of thought. We don’t actually need language in order to think.

As the chief architect of the modern concept of mind, the American philosopher Jerry Fodor, put it: “The obvious (and I should have thought sufficient) refutation of the claim that natural languages are the medium of thought is that there are non-verbal organisms that think.”

I regularly have this eerie impression that apes look right through me, perhaps because they are not distracted by language. By directing our attention to what others have to say, we neglect body language compared to animals, for whom it is all they have to go by. It is a skill they employ every day and have refined to the point that they read us like a book.

Like Galileo’s colleagues, who refused to peek through his telescope, humans are a strange lot. We have the power to analyze and explore the world around us, yet panic as soon as the evidence threatens to violate our expectations.

Neo-Creationism is not to be confused with Intelligent Design, which is merely old creationism in a new bottle. Neo-Creationism is subtler in that it accepts evolution but only half of it. Its central tenet is that we descend from the apes in body but not in mind. Without saying so explicitly, it assumes that evolution stopped at the human head. This idea remains prevalent in much of the social sciences, philosophy, and the humanities. It views our mind as so original that there is no point comparing it to other minds except to confirm its exceptional status.

At a young age, children recognize, for example, that a child looking for his rabbit will be happy to find it, whereas a child searching for his dog will be indifferent to the rabbit.23 They have an understanding of what others want. Not all humans take advantage of this capacity, which is why we have two kinds of gift-givers: those who go out of their way to find a gift that you might like, and those who arrive with what they like.

Moreover, not unlike presidential candidates who hold babies up in the air as soon as the cameras are rolling, male chimps vying for power develop a sudden interest in infants, which they hold and tickle in order to curry favor with the females.68 Female support can make a huge difference in rivalries among males, so making a good impression on them is important.

Recipients of aggression often look for a scapegoat, not unlike the way people who get reprimanded at work may come home to maltreat their spouse and children. Given their strict hierarchies, macaques are a prime example. As soon as one of these monkeys gets threatened or chased, it will threaten or chase somebody else, always an easy target. Redirected hostility thus travels down the pecking order.

Refusing perfectly fine food because someone else is better off resembles the way humans react in economic games. Economists call this response “irrational,” since getting something is by definition better than getting nothing. No monkey, they say, should ever refuse food that she’d normally eat, and no human should reject a small offer. One dollar is still better than no dollar. Sarah and I are unconvinced that this kind of reaction is irrational, though, since it seeks to equalize outcomes, which is the only way to keep cooperation flowing. Apes may even go further than monkeys in this respect. Sarah found that chimpanzees sometimes protest inequity that goes the other way. They object not only to getting less than the other but also to getting more. Grape receivers may reject their own advantage! This obviously brings us close to the human sense of fairness.47

It doesn’t actually claim animal consciousness, whatever that is. It only says that given the similarities in behavior and nervous systems between humans and other large-brained species, there is no reason to cling to the notion that only humans are conscious. As the document puts it, “The weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness.

Ironically, the study of animal cognition not only raises the esteem in which we hold other species, but also teaches us not to overestimate our own mental complexity.