Read Are We Smart Enough to Know How Smart Animals Are? Online
Authors: Frans de Waal
For these reasons, Lorenz once joked that there was nothing comparative about comparative psychology. He knew what he was talking about, having just published a seminal study on the courtship patterns of twenty different duck species.
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His sensitivity to the minutest differences between species was quite the opposite of the way comparative psychologists lump animals together as “nonhuman models of human behavior.” Think for a second about this terminology, which remains so entrenched in psychology that no one takes notice anymore. Its first implication, of course, is that the only reason to study animals is to learn about ourselves. Second, it ignores that every species is uniquely adapted to its own ecology, because otherwise how could one serve as a model for another? Even the term
nonhuman
grates on me, since it lumps millions of species together by an absence, as if they were missing something. Poor things, they are nonhuman! When students embrace this jargon in their writing, I cannot resist sarcastic corrections in the margin saying that for completeness’s sake, they should add that the animals they are talking about are also nonpenguin, nonhyena, and a whole lot more.
Even though comparative psychology is changing for the better, I’d rather avoid its leaden baggage and propose to call the new field
evolutionary cognition
, which is the study of all cognition (human and animal) from an evolutionary standpoint. Which species we study obviously matters a great deal, and humans are not necessarily central to every comparison. The field includes phylogeny, when we trace traits across the evolutionary tree to determine whether similarities are due to common descent, the way Lorenz had done so beautifully for waterfowl. We also ask how cognition has been shaped to serve survival. The agenda of this field is precisely what Griffin and Uexküll had in mind, in that it seeks to place the study of cognition on a less anthropocentric footing. Uexküll urged us to look at the world from the animal’s standpoint, saying that this is the only way to fully appreciate animal intelligence.
A century later we are ready to listen.
Do Dogs Desire?
Given the prominent role that jackdaws and little silvery fish known as three-spined sticklebacks—my favorite childhood animals—played in the early years of ethology, the discipline was an easy sell to me. I learned about it when, as a biology student, I heard a professor explain the zigzag dance of the stickleback. I was floored: not by what these little fish did but by how seriously science took what they did. It was the first time I realized that what I liked doing best—watching animals behave—could be a profession. As a boy, I had spent hours observing self-caught aquatic life that I kept in buckets and tanks in our backyard. The high point had been breeding sticklebacks and releasing the young back into the ditch from which their parents had come.
Ethology is the biological study of animal behavior that arose in continental Europe right before and after World War II. It reached the English-speaking world when one of its founders, Niko Tinbergen, moved across the Channel. A Dutch zoologist, Tinbergen started out in Leiden and accepted a position in Oxford in 1949. He described the male stickleback’s zigzag dance in great detail, explaining how it draws the female to the nest where the male fertilizes her eggs. The male then chases her off and protects the eggs, fanning and aerating them, until they hatch. I had seen it all with my own eyes in an abandoned aquarium—its luxurious algae growth was exactly what the fish needed—including the stunning transformation of silvery males into brightly red and blue show-offs. Tinbergen had noticed that males in tanks in the windowsill of his lab in Leiden would get agitated every time a red mail truck drove by in the street below. Using fish models to trigger courtship and aggression, he confirmed the critical role of a red signal.
Clearly, ethology was the direction I wanted to go in, but before pursuing this goal, I was briefly diverted by its rival discipline. I worked in the lab of a psychology professor trained in the
behaviorist
tradition that dominated comparative psychology for most of the last century. This school was chiefly American but evidently had reached my university in the Netherlands. I still remember this professor’s classes, in which he made fun of anyone who believed to know what animals “want,” “like,” or “feel,” carefully neutralizing such terminology with quotation marks. If your dog drops a tennis ball in front of you and looks up at you with wagging tail, do you think she wants to play? How naïve! Who says dogs have desires and intentions? Her behavior is the product of the law of effect: she must have been rewarded for it in the past. The dog’s mind, if such a thing even exists, remains a black box.
Its focus on nothing but behavior is what gave behaviorism its name, but I had trouble with the idea that animal behavior could be reduced to a history of incentives. It presented animals as passive, whereas I view them as seeking, wanting, and striving. True, their behavior changes based on its consequences, but they never act randomly or accidentally to begin with. Let’s take the dog and her ball. Throw a ball at a puppy, and she will go after it like an eager predator. The more she learns about prey and their escape tactics—or about you and your fake throws—the better a hunter or fetcher she will become. But still, at the root of everything is her immense enthusiasm for the pursuit, which takes her through shrubs, into water, and sometimes through glass doors. This enthusiasm manifests itself before any skill development.
Now, compare this behavior with that of your pet rabbit. It doesn’t matter how many balls you throw at him, none of the same learning will take place. Absent a hunting instinct, what is there to acquire? Even if you were to offer your rabbit a juicy carrot for every retrieved ball, you’d be in for a long, tedious training program that would never generate the excitement for small moving objects known of cats and dogs. Behaviorists totally overlooked these natural proclivities, forgetting that by flapping their wings, digging holes, manipulating sticks, gnawing wood, climbing trees, and so on, every species sets up its own learning opportunities. Many animals are driven to learn the things they need to know or do, the way kid goats practice head butts or human toddlers have an insuppressible urge to stand up and walk. This holds even for animals in a sterile box. It is no accident that rats are trained to press bars with their paws, pigeons to peck keys with their beaks, and cats to rub their flanks against a latch. Operant conditioning tends to reinforce what is already there. Instead of being the omnipotent creator of behavior, it is its humble servant.
One of the first illustrations came from the work on kittiwakes by Esther Cullen, a postdoctoral student of Tinbergen. Kittiwakes are seabirds of the gull family; they differ from other gulls in that to deter predators, they nest on narrow cliffs. These birds rarely give alarm calls and do not vigorously defend their nests—they don’t need to. But what is most intriguing is that kittiwakes fail to recognize their young. Ground-nesting gulls, in which the young move around after hatching, recognize their offspring within days and do not hesitate to kick out strange ones that scientists place in their nests. Kittiwakes, on the other hand, can’t tell the difference between their own and strange young, treating the latter like their own. Not that they need to worry about this situation: fledglings normally stay put at the parental nest. This is, of course, precisely why biologists think kittiwakes lack individual recognition.
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For the behaviorist, though, such findings are thoroughly puzzling. Two similar birds differing so starkly in what they learn makes no sense, because learning is supposedly universal. Behaviorism ignores ecology and has little room for learning that is adapted to the specific needs of each organism. It has even less room for an absence of learning, as in the kittiwake, or other biological variation, such as differences between the sexes. In some species, for example, males roam a large area in search of mates, whereas females occupy smaller home ranges. Under such conditions, males are expected to have superior spatial abilities. They need to remember when and where they ran into a member of the opposite sex. Giant panda males travel far and wide through the wet bamboo forest, which is uniformly green in all directions. It is crucial for them to be at the right place at the right time given that females ovulate only once per year and are receptive for just a couple of days—which is why zoos have such trouble breeding this magnificent bear. That males have better spatial abilities than females was confirmed when Bonnie Perdue, an American psychologist, tested pandas at the Chengdu Research Base of Giant Panda Breeding in China. She did so by spreading out food boxes over an outdoor area. Panda males were much better than females at remembering which boxes had recently been baited. In contrast, when the Asian small-clawed otter, a member of the same
arctoidea
(bear-like) family of carnivores, was tested on a similar task, both sexes performed the same. This otter being monogamous, males and females occupy the same territory. Similarly, males of sexually promiscuous rodent species navigate mazes more easily than females, whereas monogamous rodents show no sex difference.
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If learning talents are a product of natural history and mating strategies, the whole notion of universality begins to fall apart. We can expect huge variation. Evidence for inborn learning specializations has been steadily mounting.
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There are many different types, from the way ducklings imprint on the first moving object they see—whether it is their mother or a bearded zoologist—to the song learning of birds and whales and the way primates copy one another’s tool use. The more variation we discover, the shakier gets the claim that all learning is essentially the same.
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Yet during my student days, behaviorism still ruled supreme, at least in psychology. Luckily for me, the professor’s pipe-smoking associate, Paul Timmermans, regularly took me aside to induce some much-needed reflection on the indoctrination I was being subjected to. We worked with two young chimpanzees who offered me my first contact with primates apart from my own species. It was love at first sight. I had never met animals that so clearly possessed a mind of their own. Between puffs of smoke, Paul would ask rhetorically, with a twinkle in his eyes, “Do you really think chimps lack emotions?” He would do so just after the apes had thrown a shrieking temper tantrum for not getting their way, or laughed their hoarse chuckles during roughhousing. Paul would also mischievously ask my opinion about other taboo topics, without necessarily saying that the professor was wrong. One night the chimps escaped and ran through the building, only to return to their cage, carefully closing its door behind them before going to sleep. In the morning, we found them curled up in their straw nests and would not have suspected a thing had it not been for the smelly droppings discovered in the hallway by a secretary. “Is it possible that apes think ahead?” Paul asked when I wondered why the apes had closed their own door. How to deal with such crafty, volatile characters without assuming intentions and emotions?
To drive this point home more bluntly, imagine that you wish to enter a testing room with chimpanzees, as I did every day. I would suggest that rather than rely on some behavioral coding scheme that denies intentionality, you pay close attention to their moods and emotions, reading them the way you would any person’s, and beware of their tricks. Otherwise, you might end up like one of my fellow students. Despite the advice we gave him of how to dress for the occasion, he came to his first encounter in a suit and tie. He was sure he could handle such relatively small animals, while mentioning how good he was with dogs. The two chimps were mere juveniles, only four and five years old at the time. But of course, they were already stronger than any grown man, and ten times more cunning than a dog. I still remember the student staggering out of the testing room, having trouble shedding both apes clinging to his legs. His jacket was in tatters, with both sleeves torn off. He was fortunate that the apes never discovered the choking function of his tie.
One thing I learned in this lab was that superior intelligence doesn’t imply better test outcomes. We presented both rhesus monkeys and chimpanzees with a simple task, known as haptic (touch) discrimination. They were to stick their hand through a hole to feel the difference between two shapes and pick the correct one. Our goal was to do hundreds of trials per session, but whereas this worked well with the monkeys, the chimps had other ideas. They would do fine on the first dozen trials, showing that the discrimination posed no problem, but then their attention would wander. They’d thrust their hands farther so as to reach me, pulling at my clothes, making laughing faces, banging on the window that separated us, and trying to engage me in play. Jumping up and down, they’d even gesture to the door, as if I didn’t know how to get to their side. Sometimes, unprofessionally, I would give in and have fun with them. Needless to say, the apes’ performance on the task was well below that of the monkeys, not due to an intellectual deficit but because they were bored out of their minds.