You think you’re so smart
Just what makes us so brilliant is a perennial topic of inquiry in the sciences. Often this leads to lengthy boasting about our giant brains. It’s true that getting seconds on brains while the other animals were waiting for firsts on fur or feathers has been a good deal for us, but it’s also true that our understanding of how the human brain differs from the brains of other animals undergoes constant revision, and the end of the revisions is nowhere in sight. Before you sneer at the puny cortex of birds, for example, you should keep in mind that some of the things we do with our cortex they do with their striatum. Dolphins have a big cortex, but they arrange it differently, in a thin layer, and they arrange the cortical neurons differently.
As for inquiries about how we got so smart, sometimes they refer to humans only, sometimes they are about the great apes, and sometimes they are about the entire order of primates. The previously mentioned (in chapter 2) arboreal clambering theory is about the great apes, for example.
Peel me a grape
Some scientists argue that most primates are omnivorous extractive foragers, and that takes brains. Extractive foraging means that you don’t just wander around eating plants. You have to peel them or get past the thorns, the stinging hairs, the hard woody covering, or whatever means the plant has evolved to protect its tender nutritious parts.
Katharine Milton compared the foraging of spider monkeys and howler monkeys living in the same area. Howlers eat leaves, which are abundant, and spider monkeys eat fruit, which are harder to find. Perhaps spider monkey life involves more cognitive mapping, more analysis of fruit-ripening patterns, better color vision, more processing skills, and that explains why their brains are twice as big as those of howlers. (Others argue that eating leaves is not so simple, what with varying nutrients and toxins in leaves of the same species or even on the same tree.)
Machiavellian intelligence
As put forward by a group of scientists in the book Machiavellian Intelligence, edited by Richard Byrne and Andrew Whiten, the big selective advantage of intelligence might be the ability to navigate social situations. So the original plus to being smart might not have been about negotiating the physical environment or surviving its dangers, but about surviving the social environment of the group. Some suggest that primates (or some smart subset of the primates) may have a peculiarly social intelligence, geared toward understanding and manipulating relations with others. Other take the view that intelligence of a generalized kind is applied to social situations.
Nicholas Humphrey suggests that the technological challenges faced by Robinson Crusoe on the desert island are less daunting than the social difficulties presented by Man Friday. One of the demanding things about social life is that it fights back. While you figure out how to move from tree to tree, the trees just sit there, and while you figure out how to crack a nut, the nut waits patiently. But while you are figuring out how to deal with another monkey, it is figuring out how to deal with you, or a third monkey steps in to make the deal.
We are impressed with the technological sophistication of our lives, and we sometimes neglect to notice its interpersonal complexity. One study of situations that worry five-year-old humans found that 88 percent of their problems were social problems. Even some problems that seemed to be about objects were actually social problems, such as when another child was teasing them by withholding an object.
A corollary of the social intelligence idea is the grooming theory of language. Primatologist Robin Dunbar suggests that language evolved not to enable group hunting or tool use, but to substitute for and amplify the social bonding power of grooming. This is why we spend so much time—more than we think—gossiping. “Could it be that language evolved as a kind of vocal grooming to allow us to bond larger groups than was possible using the conventional primate mechanism of physical grooming?”* Language has the advantage that, while an ape can only groom one other ape at a time, you can talk to several people at once.
Byrne and Whiten hesitated before using the word “Machiavellian” to describe social intelligence. But the more they looked at the life of social primates, the more apt it seemed. “Co-operation is a notable feature of primate society, but its usual function is to out-compete other rivals for personal gain.”
Often the gain is itself social. The bonobo Matata, Kanzi’s mother, felt the need to reestablish her status in the colony after she had been away. In one incident, she jerked an infant’s leg while its mother was elsewhere but another female was nearby. The infant screamed and the enraged mother burst on the scene to see Matata threatening the other female. The mother thrashed the other female, to whom Matata was now dominant again.
Matata was also known to grab things away from a trainer, scream, and use gestures to try to enlist researcher Sue Savage-Rumbaugh against the trainer, as if she had been attacked. No wonder Matata was not interested in learning to use lexigrams—they were not presented as a way to say the things she really wanted to express, such as, “If you’re my friend, go beat her up.”
When the young Kanzi was playing too roughly, his human friends would sometimes distract him by pretending they heard something in the woods and uttering alarm calls. As they made a show of scanning the woods intently, Kanzi would stop misbehaving, come over, put his arm around someone, and join them in staring into the trees. When he was six, Kanzi began using the same fakery in awkward social situations. When there were a lot of people around him at once, Kanzi sometimes felt intimidated, and would look into the woods with a worried expression and make alarm calls in a strained tone. A hint that Kanzi was acting lay in the fact that his hair didn’t stand on end, as it did when he was truly alarmed.
Wild olive baboons observed by Barbara Smuts live in bands in which young, strong adult males are dominant to older males. To researchers’ surprise, the dominant males did not get to mate as frequently as their rank predicted. The reason was that the older males routinely formed coalitions and harassed the younger males when they were consorting with a female in estrus. Old males never harassed other old males, only young males, and they harassed them until the female ended up with another male.
In many social animals, some animals may take the roles of scroungers. They do not even try to learn some foraging skills, but instead learn how to get food other animals have obtained. Feral pigeons were presented with a task in which they had to peck a wooden stick inserted in a rubber stopper in an opaque upside-down test tube. When they did this, the stopper would come out and birdseed would fall on the ground. This is not obvious to pigeons, but they can learn to do it. If skilled birds were put in a small flock of pigeons, a few of them learned to do it too, and the rest waited until the seed scattered and rushed over to share. These scroungers followed the skilled birds, whom experimenters called producers, but did not try to produce food themselves.
If pigeons were in a cage next to a demonstrator, and there was a slanted tray so that some of the birdseed the producer got rolled into the observer’s cage, they seldom learned. In some way, the ability to scrounge inhibited their urge to learn. Were these just stupid pigeons? No: when scroungers got demonstrations during which they could no longer scrounge, but could only watch, they learned to do it.
Kindly Doctor Machiavelli
Manipulating others is not always exploiting them. The young chimpanzee Loulis was obnoxiously and repeatedly attacking two adult females who were peacefully grooming each other. His friend Dar touched him on the arm as he charged them, but Loulis ignored the touch. On his next charge his mother, Washoe, reached out and touched his leg, and Dar signed “tickle” on Loulis’s arm. Loulis turned and began to wrestle with Dar as Washoe tickled them both. Washoe and Dar had manipulated Loulis into behaving better.
At the Arnhem Zoo, two chimpanzee mothers watched as their small children played together. Next to the mothers, Jimmie and Tepel, slept Mama, the greatly respected matriarch of the colony. The children’s wrestling turned into a screaming fight. Ji
mmie and Tepel were uneasy. They looked at each other, looked at the fighting kids, looked at each other, shifted restlessly. Apparently neither dared intervene for fear of antagonizing the other. Tepel poked Mama until she woke up, and pointed at the squabbling children. Mama rose to her feet, waved one arm, and gave a loud grunt-bark. The kids stopped fighting, and Mama went back to sleep.
“In the laboratory, when a normal primate has the choice of responding to a social cue or to objects, he turns first to the social cue,” writes Alison Jolly. “During early insight tests, primates from lemur…to chimpanzee…would beg from the experimenter before attempting to solve a new problem (a quite accurate assessment of the real relationships of the situation).” Muni, a young gorilla, turned to humans to solve her problems. Confronted by an object suspended out of her reach, her first reaction was either to lead a person under the object and use them as a ladder or to lead them under the object and request that they get it for her. As for bonobos, it has been pointed out that “Kanzi’s most complex symbol communications occur in social interactions involving three or more individuals.”
The Case of the Unreliable Narrator
Vervet monkeys learn about other monkeys’ reliability. They have three calls that indicate threat from a neighboring vervet group, the grunt, the wrr, and the chutter. If those tireless audio enthusiasts Robert Seyfarth and Dorothy Cheney play tapes over and over of a particular vervet’s wrr when there is no other group around, the vervets who hear it eventually ignore that vervet’s wrr. If they hear her chutter, they ignore that too, because they consider her unreliable. But if they instead hear the chutter of another vervet, one who hasn’t worn them out with false alarms, they respond.
Learning your position in society
Greylag goose couples have ranks in the flock, and their goslings learn this. Goose families present united fronts against other families, with the goslings as well as the parents stretching out their necks and making threat displays. “It is from their participation in disputes involving the family that young geese come to recognize the rank their parents occupy in the goose flock. The youngsters automatically adopt the same rank, and it is amusing to see a half-grown goose cheekily approach a full-grown gander and, for example, drive him away from the food dish,” Lorenz writes. If a gosling tries this when its family isn’t nearby, the lower-ranking adult may give it a thrashing.
I want her to know her heritage
Japanese macaques inherit their mothers’ rank. By six months they know their rank, largely from observing their mothers. One way high-ranking macaque mothers convey this information is by officious interference in children’s play. A low-ranking mother will not intervene when her child is playing with another child unless her child utters a distress call. High-ranking mothers often swept down when their children were playing happily with others and “rescued” them from nonexistent peril, threatening those of lower rank. With such displays, “high-born females appeared to control and initiate the matrilineal transmission of rank, rather than act simply as models for the infants,” write primatologists Bernard Chapais and Carole Gauthier.
Ringtailed lemurs do not inherit rank. Mothers often sit callously by and watch as young ringtails fight. The young lemurs establish dominance in play-fighting that turns to angry grappling. At the end the winner stays put and the loser runs to its mother for comfort. Learning whom you can beat takes place on a case-by-case basis, and it’s not transitive. Just because lemur Alef is dominant to lemur Beth and lemur Beth is dominant to lemur Gimmel doesn’t mean that Alef is also dominant to Gimmel. Gimmel can easily be dominant to Alef.
Zap! You’re a sweetie
Not a recent experiment: there were four macaques in a monkey colony. Ali, the “boss,” was strong, mean, and ill-tempered. Sometimes he expressed his anger by grimacing and biting his own hand, which doesn’t sound like a happy monkey, but this was small comfort to Elsa, whom he bullied. He was friendly to the other female, Sarah, and either ignored or was hostile to Lou, the smaller male. The four monkeys were placed in a cage three feet by three feet by seven, with a lever at one end. Surgery was performed on Ali and Sarah to implant electrodes in their brains. The electrodes could be triggered by pushing the lever.
When the lever stimulated electrodes in Sarah’s brain, no one cared. But when the lever stimulated Ali’s caudate nucleus, he didn’t feel like doing much of anything—he didn’t eat, drink, walk, groom himself, or attack Elsa or Lou. Elsa figured this out the second day and spent a lot of time pushing the lever—while looking at Ali. Elsa was manipulating Ali, but who can blame her?
Theory of mind
If you’re going to have a social life, it’s very helpful to have a theory of mind, that is, to recognize that others have wishes, fears, and knowledge of their own. This is another of those hotly debated areas of study. It’s not hard to find examples in which animals seem to have no conception whatsoever of the knowledge and feelings of others. The occasions when they do seem to have that insight are more interesting. (Small children may tell amusing lies because their theory of mind is not yet developed.)
Psychologists were astounded a few decades ago when it was found that babies often imitate people sticking out their tongues. Andrew Meltzoff made this scientific discovery (no doubt it had been the personal discovery of many people through the ages) in month-old babies and then arranged to be called to delivery rooms to see if newborns do it. Babies as young as 42 minutes stuck out their tongues in imitation. They also imitated lip protrusion and mouth opening. Somehow, without experience, babies make a connection between their own mouth or tongue, which they have never seen, and the face of the adult making faces at them. “Nature ingeniously gives us a jump start on the Other Minds problem. We know, quite directly, that we are like other people and they are like us,” write Meltzoff, Alison Gopnik, and Patricia Kuhl in The Scientist in the Crib. “Imitation is an innate mechanism for learning from adults, a culture instinct,” they write. “In fact, recent research suggests that most other animals don’t learn through imitation in this way.”
Masako Myowa replicated these tests with an infant chimpanzee between 5 and 15 weeks old. Up until 12 weeks, the little ape opened her mouth when humans hovering over her opened their mouths, stuck out her tongue when they stuck out their tongues, and protruded her lips when they protruded theirs. After 12 weeks she gave it up.
Deception
Deception is often considered a sign that the deceiver may have a theory of mind. In an oceanarium in Hawaii, Ola, a baby Pseudorca whale, was friends with Keiki, a teenaged bottlenose dolphin. At night, Keiki would leap over a gate between tanks to be with Ola. (Ola was not as skilled a jumper.) The staff didn’t like this, because it was a nuisance to separate the two animals for the morning show. They attached a wide, heavy plank over the partition to make it look too scary to jump over. A few days later, when the staff arrived in the morning, the plank was in the water and Keiki was in Ola’s tank. Perhaps some softhearted employee had levered it off so the animals could be together. But it happened every night. Finally a trainer hid and watched Ola prop his tail against the floor of the tank and use that leverage to push the plank off the gate with his nose. The striking thing was that Ola knew not to do this when people were watching.
The plank was more firmly attached, but the staff instituted a daily playtime during which Keiki and Ola could be together in the main tank.
In the mirror, a monster! A beast! A vision of beauty!
A famous and controversial way of exploring animal mentality is the mirror test. People learn what a mirror image is, but most of us encountered mirrors so young that we don’t remember learning it. Most animals never figure out that a mirror image is of themselves. Kotar, a captive killer whale, was displeased with the killer whale he saw looking back at him from a big mirror his keepers rigged up. He touched the mirror, looked behind it, looked beneath it, and shook his head to threaten it. Lorenzo, a tame scrub jay, could never pass a mirror without del
ivering a threat or a peck. Dogs and cats learn that the mirror image is not another dog or cat and conclude that it is something they can ignore, but never show signs of grasping the connection between the image’s movements and their own.
Captive chimpanzees presented with mirrors typically begin by treating the image as another chimpanzee, whom they usually try to menace. Then they look behind the mirror and then, often, they settle down for some serious primping. In 1970, Gordon Gallup Jr., wishing to test whether chimpanzees like this were really recognizing themselves, came up with the idea of making a mark on a chimpanzee’s head while it was unconscious. The marking paint was odorless, so the only way the chimpanzee could know the mark was there would be if it looked in the mirror and realized that the painted ape it saw was itself.
The chimpanzees were startled at the sight. They ran their fingers over the marks on their heads—their real heads, not their reflected heads—and looked at their fingers to see if the paint had come off on them. They smelled their fingers.
The significance lies in the idea that a being who can recognize its image in this way must have a concept of self. Thus mirror self-recognition is thought to indicate self-awareness. “Without a sense of self, how would you know who you were seeing when confronted with your reflection in the mirror?” write scientists Gordon Gallup Jr., James Anderson, and Daniel Shillito. Perhaps recognizing self leads to inferring mental states to others—theory of mind. It is argued that this ability appears in children at the age they begin to recognize their mirror image.
In general, chimpanzees pass the mark-and-mirror test, bonobos pass, orangutans pass, and at least one gorilla passes. People pass after they’re 18 to 24 months old. Outside the primate order, not much mirror skill has been found. Elephants in the National Zoo didn’t pass the mark test. Neither did two young grey parrots.
Becoming a Tiger: The Education of an Animal Child Page 40