The paradox is this: “It has repeatedly been demonstrated in the artificial situations of the laboratory that the anthropoid apes possess impressive powers of creative reasoning,” explains Humphrey, “yet these feats of intelligence simply do not have any parallels in the behavior of the same animals in their natural environment. I have yet to hear of any example from the field of a chimpanzee . . . using his full capacity for inferential reasoning in the solution of a biologically relevant practical problem.” The same might be said of humans, comments Humphrey. Suppose, for example, Einstein were to be observed as primatologists observe chimpanzees, through a pair of field glasses. He would see flashes of genius from the great man only rarely. “He did not use [his genius], for he did not need to use it, in the common world of practical affairs.”
Either natural selection has been profligate in making primates—including humans—smarter than they really need to be, or their daily life is more intellectually demanding than it appears to the outside observer. Humphrey came to believe that the second of these alternatives is correct: specifically, that the social nexus of primate life presents a sharp intellectual challenge. The primary role of creative intellect, he suggests, is “to keep society together.”
Primatologists now know that the network of alliances within primate troops is extremely complex. Learning the intricacies of such a network, as individuals must if they are to succeed, is difficult enough. But the task is made vastly harder by the constant shifting of alliances, as individuals constantly seek to improve their political power. Always looking out for their own best interests, and for the interests of their closest relatives, individuals may sometimes find it advantageous to break existing alliances and form new ones, perhaps even with previous rivals. Troop members therefore find themselves in the midst of changing patterns of alliances, and a keen intellect is demanded in playing the changing game of what Humphrey refers to as social chess.
Players of social chess have to be more skillful than players of the ancient board game, because not only do the pieces unpredictably change identity—knights becoming bishops, pawns becoming castles, and so on—but also allies occasionally switch sides and become the enemy. Players of social chess must be constantly alert, on the lookout for potential advantage, watchful for unexpected disadvantage. How do they do it?
The challenge for individuals in primate societies is to be able to predict the behavior of others. One way would be for individuals to have a huge mental bank in their brains, which stored every possible action of their fellow troop members and their own appropriate responses. This is how the powerful computer program Deep Thought achieves Grand Master status at chess. However, computers are vastly faster than living brains are at sifting through all possible combinations for any particular set of circumstances. Some other means is required. If, for example, individuals were able to monitor their own behavior, rather than merely operate as computerlike automatons, then they would develop a heuristic sense of what to do under certain circumstances. By extrapolation, they might then be able to predict the behavior of others under the same circumstances. This monitoring ability, which Humphrey calls an Inner Eye, is one definition of consciousness, and it would confer considerable evolutionary advantage in those individuals that possessed it.
Once consciousness was established, there was no going back, for individuals less well endowed would be at a disadvantage. Similarly, those with a slight edge would be further favored. An arms race would ensue, driving the process ever onward, boosting intelligence and sharpening self-awareness. As the Inner Eye became ever more observant, inexorably there would emerge a real sense of self, a reflective consciousness, an Inner I.
The hypothesis, which was part of the development of the social intelligence hypothesis, attracted a lot of interest and support. In a review of primate studies, published in 1986 in Science, Cheney, Seyfarth, and Barbara Smuts noted the importance of intelligence in social contexts, as compared with its importance in meeting the demands of technology. And Robin Dunbar examined the differing amounts of cerebral cortex—the “thinking” part of the brain—in various species of primate. He discovered that those species that lived in large groups, and therefore faced the more complex games of social chess, had the most extensive cerebral cortex. “This is consistent with the social intelligence hypothesis,” he concluded.
Two lines of evidence have been important in the revolution in the understanding of animal behavior—a revolution that eroded the behaviorist dogma that animals don’t have minds. One was a pioneering set of experiments designed to detect self-awareness—that is, signs of self-recognition—in animals other than humans. The second involved looking for signs of tactical deception in primates in their natural habitat.
An experience as private as consciousness is frustratingly beyond the usual tools of the experimental psychologist. This may be one reason that many researchers have shied away from the notion of mind and consciousness in nonhuman animals. In the late 1960s, however, Gordon Gallup, a psychologist at the State University of New York, Albany, devised a test of the sense of self: the mirror test. If an animal were able to recognize its reflection in a mirror as “self,” then it could be said to possess an awareness of self, or consciousness. Pet owners know that cats and dogs react to their image in a mirror, but often they treat it as that of another individual whose behavior very soon becomes puzzling and boring. (Nevertheless, those same pet owners will swear that their cat or dog is self-aware.)
The experiment—which Gallup dreamed up one morning while shaving—called for familiarizing the animal with the mirror and then marking the animal’s forehead with a red spot. If the animal saw the reflection as just another individual, it might wonder about the curious red spot and might even touch the mirror. But if the animal realized that the reflection was of itself, it would probably touch the spot on its own body. The first time Gallup tried the experiment with a chimp, the animal acted as if it knew that the reflection was its own; it touched the red spot on its forehead. Gallup’s report of the experiment, published in a 1970 article in Science, was a milestone in our understanding of animal minds, and psychologists wondered how widespread self-recognition would prove to be.
Not very, is the answer. Orangutans passed the mirror test, but, surprisingly, gorillas did not. In less formal situations, some observers claim to have seen gorillas use mirrors as if they recognized their own image, which they take to indicate a sense of self in these animals. A mental Rubicon, with self-awareness on one side and its absence on the other, would make sense if the self-aware side included humans and the great apes, with the rest of the primates and other animals on the other. However, some primatologists considered this too exclusive a division, given their observations of the complex social lives of many monkey species. A test of this exclusivity emerged recently, that of “tactical deception.”
Andrew Whiten and Richard Byrne, of the University of St. Andrews in Scotland, coined this term, which they define as “an individual’s capacity to use an ‘honest act’ from his normal repertoire in a different context, such that even familiar individuals are misled.” In other words, one animal intentionally lies to another. In order to be able to deceive intentionally, an animal must have a sense of how its actions appear to another individual. Such an ability requires self-awareness. If deception occurs at all, it is likely to be rare: like the boy who cried “Wolf!” you can’t do it very often if your credibility is to be preserved.
Byrne and Whiten became interested in deception after seeing several instances of what could be interpreted as such among a troop of baboons they were observing in the Drakensberg Mountains of southern Africa. For instance, one day Paul, a juvenile male, approached Mel, a mature female, who was engaged in unearthing a succulent tuber. Paul looked around, and saw that no other baboons were in sight, although he was surely aware that they were not far away. Paul let out a piercing scream, as if he were in danger. Paul’s mother, who was dominant to Mel, reacted as any pro
tective mother would: she rushed to the scene and drove Mel, the apparent offender, away. Paul then casually ate the abandoned tuber. Had Paul thought, “Hmm, if I scream, my mother will assume Mel is attacking me. She’ll run to defend me, and I will be left with the juicy tuber to eat"? If true, this would be an example of tactical deception.
Byrne and Whiten thought it might be true, and informally canvassed fellow primatologists about their field observations. Many stories similar to Paul’s were told, although few had ever made it into the pages of the scientific literature, being anecdotal and therefore unscientific. Byrne and Whiten conducted surveys of more than a hundred of their colleagues, in 1985 and again in 1989, soliciting accounts of putative tactical deception. They received more than three hundred. The instances were not confined to observations of apes but included observations of monkeys as well. Interestingly, no one claimed to have seen deception in primates other than monkeys and apes, such as bush babies and lemurs.
The problem primatologists face in looking for evidence of deception is this: Is the action truly an example of an individual reasoning, based on a sense of self? Or is it merely the outcome of learning, which does not require a sense of self? Paul, for instance, might simply have learned that under the circumstances he encountered, his screaming would gain him access to Mel’s tuber, in which case his action would be a learned response and not an act of tactical deception.
When Byrne and Whiten applied strict criteria to the supposed examples of deception, ruling out as carefully as they could possibilities of learning, they found that of the 253 cases assembled in the 1989 survey, only 16 could be said to reflect true tactical deception. All of these cases were apes, and most were chimpanzees. I’ll give one example, which was observed by the Dutch primatologist Frans Plooij while at Gombe Stream Reserve, in Tanzania.
An adult male chimpanzee was alone in a feeding area when a box was opened electronically, revealing the presence of bananas. Just then, a second chimp arrived, whereupon the first one quickly closed the box and ambled off nonchalantly, looking as though nothing unusual was afoot. He waited until the intruder departed, and then quickly opened the box and took out the bananas. However, he had been tricked. The intruder had not left but had hidden, and was waiting to see what was going on. The would-be deceiver had been deceived. This is a persuasive example of tactical deception.
Observations such as these open a window onto the mind of chimpanzees. These animals evidently experience a significant degree of reflective consciousness, a conclusion that researchers who work with chimps on a day-today basis enthusiastically endorse. Chimpanzees exhibit a strong sense of awareness in the way they interact with each other and with humans. They are mind readers as humans are, but more limited in their scope.
In humans, mind reading goes beyond simply predicting what others will do under certain circumstances: it includes how others might feel. We all experience sympathy, or empathy, for others when they face situations we know to be painful or distressing. Vicariously, we experience the anguish of others, sometimes so intensely as to suffer physical pain. The most poignant vicarious experience in human society is the fear of death, or simply death awareness, which has played a large part in the construction of mythology and religion. Despite their self -awareness, chimpanzees at best seem puzzled about death. There are many anecdotal accounts of individuals, or even families, being distressed or disoriented when a relative dies. For example, when a small infant dies, its mother sometimes carries the tiny corpse around for a few days before discarding it. The mother seems to be experiencing bewilderment rather than what we call grief. But, how would we know? More significant, perhaps, is the lack of what we would recognize as sympathy for the bereaved mother from other individuals. Whatever the mother suffers, she suffers alone. The chimpanzees’ limitation in empathizing with others extends to themselves as individuals: no one has seen evidence that chimps are aware of their own mortality, of impending death. But, again, how would we know?
What can we say about how self -aware our ancestors were? Some 7 million years have passed since humans and chimpanzees shared a common ancestor. We must therefore be cautious about assuming that chimps have remained unchanged, and that by looking at chimps we are effectively looking at that common ancestor. Chimps must have evolved in various ways since diverging from the humanlineage. But it is plausible to suggest that the common ancestor, a large-brained ape that lived a socially complex life, would have developed a chimpanzee level of consciousness.
Let’s assume that the common ancestor of humans and African apes possessed a level of self-awareness equivalent to that experienced by modern chimpanzees. From what we’ve learned about the biology and social organization of the australopithecine species, they were essentially bipedal apes: the social structure among these species would have been no more intense than we see among modern baboons. There is therefore no cogent reason why their level of self-awareness would have been enhanced during the first 5 million years of the human family’s existence.
The significant changes that occurred with the evolution of the genus Homo, in brain size and architecture, social organization, and mode of subsistence, probably also marked the beginning of a change in the level of consciousness. The beginnings of the hunting-and-gathering way of life surely increased the complexity of the social chess our ancestors had to master. Skilled players of the game—those equipped with a more acute mental model, a sharper consciousness—would have enjoyed greater social and reproductive success. This is grist for natural selection, which would have raised consciousness to higher and higher levels. This gradually unfolding consciousness changed us into a new kind of animal. It transformed us into an animal who sets arbitrary standards of behavior based on what is considered to be right and wrong.
Much of this, of course, is speculation. How can we know what happened to our ancestors’ level of consciousness during the past 2.5 million years? How can we pinpoint when it became as we experience it today? The harsh reality anthropologists face is that these questions may be unanswerable. If I have difficulty proving that another human possesses the same level of consciousness I do, and if most biologists balk at trying to determine the degree of consciousness in nonhuman animals, how is one to discern the signs of reflective consciousness in creatures long dead? Consciousness is even less visible in the archeological record than language is. Some human behaviors almost certainly reflect both language and a conscious awareness, such as artistic expression. Others, such as the making of stone tools, may, as we’ve seen, give clues to language but not to consciousness. However, there is one human activity redolent of consciousness that sometimes leaves its mark in the prehistoric record: deliberate burial of the dead.
Ritual disposal of the dead speaks clearly of an awareness of death, and thus an awareness of self. Every society has ways in which death is accommodated as part of its mythology and religion. There are myriad ways in which this is done in the modern age, varying from extensive care of the corpse over a long period, perhaps involving moving it from one special location to another after a period of a year or even more, to minimal attention to the body. Sometimes, but not often, the ritual involves burial. Ritual burial in ancient societies would offer the opportunity for the ceremony to become frozen in time, available later for the archeologist to puzzle over.
The first evidence of deliberate burial in human history is a Neanderthal burial not much more than 100,000 years ago. One of the most poignant burials was a little later, some 60,000 years ago, in the Zagros Mountains of northern Iraq. A mature male was buried at the entrance to a cave; his body had apparently been placed on a bed of flowers of medicinal potential, judging by the pollen that was found in the soil around the fossilized skeleton. Perhaps, some anthropologists have speculated, he was a shaman. Earlier than 100,000 years ago, there is no evidence of any kind of ritual that might betray reflective consciousness. Nor, as noted in chapter 6, is there any art. It’s true that the absence of such evidence does n
ot definitively prove the absence of consciousness. But neither can it be adduced in support of consciousness. I would find it surprising, however, if the immediate ancestors of archaic sapiens people, late Homo erectus, did not have a level of consciousness significantly greater than that of chimpanzees. Their social complexity, large brain size, and probable language skills all point to it.
Neanderthals, as I’ve suggested, and probably other archaic sapiens, did have an awareness of death and therefore undoubtedly a highly developed reflective consciousness. But was it of the same luminosity as we experience today? Probably not. The emergence of fully modern language and fully modern consciousness were no doubt linked, each feeding the other. Modern humans became modern when they spoke like us and experienced the self as we do. We surely see evidence of this in the art of Europe and Africa from 35,000 years onward and in the elaborate ritual that accompanied burial in the Upper Paleolithic.
Every human society has an origin myth, the most fundamental story of all. These origin myths well up from the fountainhead of reflective consciousness, the inner voice that seeks explanations for everything. Ever since reflective consciousness burned brightly in the human mind, mythology and religion have been a part of human history. Even in this age of science, they probably will remain so. A common theme of mythology is the attribution of humanlike motives and emotions to nonhuman animals—and even to physical objects and forces, such as mountains and storms. This tendency to anthropomorphize flows naturally from the context in which consciousness evolved. Consciousness is a social tool for understanding the behavior of others by modeling it on one’s own feelings. It is a simple and natural extrapolation to impute these same motives to aspects of the world that are nonhuman but are nonetheless important.
The Origin of Humankind Page 15