Egyptian vultures, Galapagos woodpecker finches, sea otters, some gorillas, and above all chimpanzees resemble human beings in their ability to use tools. But for much of the twentieth century, the ability to make tools was thought to be a skill unique to man and distinctively a product of human intelligence. In 1960, a young British primatologist named Jane Goodall pushed humanity off this self-congratulatory pedestal. Through arduous field studies in the forests of East Africa, she observed chimpanzees stripping twigs to make rods for termite-fishing.

Goodall owed the chance to make this seminal discovery to Louis Leakey, the white Kenyan paleoanthropologist who between the 1920s and his death in 1972 unearthed significant fossil clues to human ancestry. Beginning in the late 1950s, he also promoted the study of primates by others—Goodall with chimpanzees; Dian Fossey, the gorilla specialist; and (in Borneo) Biruté Galdikas, who studied orangutans—which he did by encouraging them, raising money for their work, and arranging official permission for it from various East African governments. (He thought that women would be best suited to studying primates in the wild, because they had greater patience—needed for the hard task of finding, tracking, and watching great apes live their leaf-obscured and distance-shrouded lives—and greater sensitivity to social nuance.)

Leakey hoped this primate research would throw light on the nature of mankind’s ancestors, whose bones, tools, and dinner leftovers he had been excavating at places like Olduvai Gorge—a thirty-mile-long ravine in the Serengeti Plains of northern Tanzania. When Goodall sent a report to him of her observations of tool-making activities by chimpanzees, he cabled back, “Now we must redefine tool, redefine man, or accept chimpanzees as human.” It is the third option that has, in effect, since been taken.

Goodall’s remarkable career is the joint outcome of luck and determination. Born in 1934 to parents who divorced when she was young, Goodall was brought up in a modest seaside town in England. When she arrived in Kenya at age twenty-three in 1957, she had not a shred of qualification apart from secretarial training and an interest in animals. But she was hired by Leakey as his secretary, worked closely with him, and in 1960 Leakey sent her to the Gombe Stream nature reserve in Tanganyika (now Tanzania) to study the area’s chimpanzee population.

Following the discoveries about tool-making, Leakey arranged for Goodall to return to England to pursue a Ph.D. in ethology, despite her lack of previous academic credentials. After finishing her degree, she returned to Gombe, where her research was sponsored by the National Geographic Society. In 1967, National Geographic published Goodall’s My Friends the Wild Chimpanzees, a popular illustrated book that went some way to repaying the society for its support. She has since published a dozen more books, of which easily the most famous is In the Shadow of Man (1971), which encouraged its many readers to think of chimpanzees as far more closely related to themselves than they had imagined. By 1977, Goodall had established the Jane Goodall Institute, a nonprofit foundation based in the United States that supports research and protection of the primate populations at Gombe. Since the mid-1980s, her chief preoccupation has been chimpanzee conservation rather than research, an urgent task given the increasing human pressure on chimpanzee territory in Africa, and the continuing poaching of chimpanzees for use in scientific and medical research.

Observing chimpanzees among the trees on the mountain slopes of Gombe in 1960, Jane Goodall could not have realized how revolutionary her discoveries would prove to be. Beginning her work without the encumbrance of scientific training, she was able to retain a child’s sensitivity to the personality and individuality of animals without the distraction of established methodologies and theories. She interpreted animal behavior by trusting her intuition, and it was this that enabled her to think about chimpanzees, and by extension their relation to humankind, in new ways.

In addition to her findings about tool-making, Goodall was the first to observe chimpanzees cooperating in hunts and eating meat, and taking part in organized warfare between chimpanzee tribes. These discoveries were made possible by the practice of following and watching chimpanzees in difficult wooded terrain over long periods of time, and they required accurate identification of individual chimps and a slowly acquired sense of the personalities of each and the relationships among them. Goodall gave names to the members of the chimpanzee tribes she studied, and made assumptions about their behavior in frankly emotional and intentional language. For example, she described the central importance of close and lifelong bonds between chimp mothers and their offspring, and movingly evoked the grief experienced by young chimpanzees when their mothers died, and by older chimpanzees when siblings or long-standing comrades died.

Although Goodall’s research had turned out to be disconcertingly fruitful, many ethologists considered her anthropomorphic assumptions unscientific. They were also bothered by her intervention in the chimp populations she studied. To ease the task of observation she set up feeding stations to attract chimpanzees to her camp; critics say this might have led to the “tribal warfare” she later described, in which her local chimpanzees attempted to defend the new food source against interlopers. By mixing so freely with the subjects of her study, her critics charge, Goodall was polluting the evidence on which she based her conclusions.


These methodological eccentricities were mainly a feature of Goodall’s early period at Gombe, when it was still a one-woman project. As Gombe grew in the 1970s into an international center for chimpanzee studies, with a staff of researchers, standard scientific methods for collecting systematic data were instituted. It would be difficult to fault the work now done there. But many of the most important insights from Gombe would not have been possible without Goodall’s unorthodox approach.

Around the time Goodall was starting her research in Gombe, Leakey was discovering more bones in Olduvai Gorge, including fragments of Homo erectus and Homo habilis. The dating of these fossils pushed human ancestry back by two million years. Combined with Goodall’s observations about chimpanzee behavior, the fossil discoveries raised important new questions about human nature, and established primatology as an influential field for exploring them.

In the nineteenth century Darwin had placed human beings firmly in nature, upending the long-prevailing assumption that mankind was a divine creation among the flora and fauna provided for its use. (That Darwin himself bore a vague resemblance to a patriarchal colobus monkey proved useful to Victorian cartoonists and detractors who were offended by the idea of a “descent of man.”) But whereas the physiological similarity between apes and humans was sufficient to make primates a symbol of the degenerate and beastly side of man, through roughly the first half of the twentieth century, the comparison remained almost entirely imaginative, as for example in films (King Kong, Planet of the Apes, Tarzan) and in short stories in lurid magazines. For a long time the accumulating evidence from paleoanthropology, following the nineteenth-century discovery of Neanderthal man, had little influence on primate ethology. In the work of Eugene Marais (The Soul of the Ape, 1919), for example, and of biologists such as Robert Yerkes of Yale University in the years between the two world wars, the question of primates’ relation to human beings was not given much consideration.

But Goodall’s early findings about chimpanzees suggested that comparisons between human beings and apes could teach us much about ourselves. This idea was strengthened by the identification by paleoanthropologists of common ancestors in the recent evolutionary past (a mere five million years ago in the case of chimpanzees and human beings). By the time Goodall’s In the Shadow of Man was published in 1971, her observations at Gombe had already brought new interest to primate research, and scientists had begun to study genetic similarities between primates and humans. Chimpanzees, for example, were discovered to share 98.4 percent of their genes with humans.

In 1975 Edward O. Wilson coined the word “sociobiology” to describe a “new synthesis” of biology, sociology, ethology, anthropology, population genetics, and other pertinent disciplines. Sociobiology’s premise is that evolutionary pressures have given shape to social behavior in animals so as best to enhance a species’ reproductive success. As applied to lemurs, dogs, and other lower mammals, the idea is illuminating. As applied to human beings it is controversial, because it seems to assume some form of genetic determinism in human behavior. One question prompted by Goodall’s observations about tool-making, communal hunting, grooming behavior, and family ties among chimpanzees was which side of this debate her findings supported.

For some critics of sociobiology, the implication that certain patterns of behavior are genetically determined suggested, controversially, that we can do nothing but accept them. If, for example, male aggression, which might enhance male reproductive success (by frequent rape, say), is a hardwired natural tendency, does it mean that we can do nothing about it? One response to this question is to reassert the claim of human exceptionalism owing to the possession of intelligence and culture, capacities that scientists such as Richard Lewontin and Stephen Jay Gould have described as having a far greater influence on human behavior.

Jane Goodall’s description of relations between chimpanzee mothers and their offspring, of separation anxiety, and of grief in response to death, however, seemed to offer support for the sociobiological view. Throughout the mammalian world, mothers are jealously protective of their offspring, and culture and advanced intelligence have nothing to do with it. Maternal behavior is instinctive. In a review of the celebrated attack on sociobiology by Lewontin and Steven Rose, Not in Our Genes (1985), Richard Dawkins denied that sociobiology claims that human social arrangements are inevitable products of genes alone. Clearly, description of similar behaviors observed in chimpanzees and humans invites explanation “in terms of” genetic factors. But Dawkins insisted that the phrase “in terms of” does not entail “inevitably because of,” especially in the human case where historical and cultural factors indeed play a large part.


Yet historical and cultural factors can themselves be seen as evolutionary adaptations. In place of thick fur and big teeth, humans evolved a high degree of self-reflective intelligence, which allows many possible strategies for dealing with the environment. Even if the fundamental drive is our genes’ imperative to maximize the number of their copies in succeeding generations, and even if in all creatures other than humans the result is a relatively inflexible repertory of strategies—chimpanzees do not write piano concertos or design dresses as part of theirs—it does not follow that the creative variety of human capacities cannot ultimately be explained by evolutionary pressures.

Jane Goodall’s observations at Gombe had the effect of making a sociobiological account of humankind distinctly more plausible. They also had the effect of resituating apes as true relations of humans, rather than as their beastly mirror-image. When Peter Singer and others proposed that the great apes should be brought within the same sphere of moral concern as human beings, the idea was greeted with sympathy in many quarters precisely because Goodall’s revelations about chimpanzee kinship were so convincing.

There is no doubt that the influence of Goodall’s discoveries was helped by the fact that she made them as a charming and eloquent young woman—in the popular imagination, a fresh-faced, pony-tailed English girl in the dark depths of the jungle—and this gave what she reported a luminous edge. In Jane Goodall: The Woman Who Redefined Man, Dale Peterson gives a great deal more nuance to the Goodall myth, showing that her early work at Gombe was slow and often difficult. Closely following Goodall’s diary entries, he describes her setting off each morning up the forested mountain slopes of Gombe in hope, often disappointed, of seeing her chimpanzees; scrambling through inhospitable and sometimes dangerous terrain to follow their distant calls; and occasionally coming face-to-face with a large male, noting the surprise and puzzlement in his facial expressions as if he were human.

It was only after months of such pursuit, and a bout with malaria, Peterson writes, that Goodall finally made her breakthrough observing a chimpanzee turn a stalk of grass into a tool for digging termites:

The great moment took place on Friday, November 4. Since Short had gone into Kigoma on an errand, Jane was wandering in the mountains on her own. She started up the Kakombe valley behind her camp, but, following the auditory trail of cries and hoots, she moved north, walking on a high ridge trail above the Linda valley. She was passing within 100 yards of a termite mound when, at 8:15, she happened to notice a “black object” in front of the mound. Jane “didn’t remember seeing a tree stump there,” as the journal indicates, and so she looked more closely and realized it was a chimp. “I quickly dropped down, & crawled through the sparse dry grass until I reached a tree with greenery sprouting at the base.” Looking through the screen of those leaves, she observed the ape, about 50 yards away, “picking up things” from the termite mound and putting them in this mouth. Eating. His back was turned toward her. Jane carefully moved around to get a better view, while the chimp turned around, facing her—but still not aware, apparently, that he was being watched.

“Then, [Goodall wrote in her journal] very deliberately he pulled a thick grass stalk towards him & broke off a piece about 18″ long. Then, unfortunately, he turned his back on me again. (He picked off the grass with his right hand.) After some minutes he climbed onto the top of the mound, but still with his back to me. Then he got down—after peering hard in my direction, & vanished down the hill. After 5 mins or so, when I thought he had seen me & gone, he appeared, wandering away nonchalantly, away from me. Then he stopped, put up his left hand up onto a low branch, stood up, & looked around. Apparently changed his mind, for he turned round & came straight towards me. As he walked along, he gave the impression of ‘swinging along,’ his head slightly swinging from side to side. Fairly bald. Face not too dark. White beard.”

But Peterson’s technique of interposing such gripping passages in longer stretches of dry background and tiresome detail has the effect of submerging the most interesting parts of Goodall’s life. Still, he is alert to the controversies that surrounded her methodology, and his sensitive account of the conservation efforts that have marked the more recent phases of her career goes some way to justify the length at which he describes them. Since the mid-1980s Goodall has put her reputation to excellent effect in championing the survival of endangered primate populations. This she has done by lobbying Congress for restrictions on laboratory use of primates; by obtaining an endangered species classification for chimpanzees; and by establishing numerous chimpanzee reserves in Africa.

More recently, in her new book, Harvest for Hope, Goodall criticizes our dependence on environmentally damaging agribusiness and factory farming. As a corrective, she advocates vegetarianism, but also a return to consuming only organically grown local produce in season. Two effects, she argues, would follow: the soil, water table, rivers, and seas would start to recover from the chemical run-off of fertilized crops, and a large volume of greenhouse gas emitted by international transport of foodstuffs would not be added to the atmosphere. These are not new ideas but they are worth serious consideration.

Baboon Metaphysics, by Dorothy Cheney and Robert Seyfarth, shows how far ethology has come since Jane Goodall’s early years at Gombe. An account of Cheney’s and Seyfarth’s field research into the social interactions of baboons, this is an impressive story, not just because of the care that went into the observations and experiments they record, but also in the philosophical sophistication of their thinking about the mental life of baboons.

Cheney and Seyfarth cite a remark from one of Darwin’s notebooks as the starting point for their work: “He who understands baboon would do more towards metaphysics than Locke.” By “baboon” Darwin undoubtedly meant the language, or at least the system of communication, of baboons, and by “metaphysics” he did not mean quite what this word now denotes (namely, inquiry into the fundamental nature of reality) but philosophy in general—especially ethics and the nature and sources of knowledge. It is often forgotten that the term “philosophy” in Darwin’s day was only just ceasing to mean “science,” and that “metaphysics” was the standard term used by his forebears and older contemporaries to mean what we now call philosophy. Reconstructing the intention of Darwin’s remark, we see what he had in mind: now that religious explanations will no longer do, the significance and value of things human must be understood by placing mankind squarely in nature, and learning as much as possible from mankind’s closest relatives about how we came to be what we are. Thus understood, Darwinian metaphysics is sociobiology as applied to human beings.

For Cheney and Seyfarth the implication of Darwin’s dictum is that ethological study of monkeys and apes can yield clues to the nature of the mind. The target of their specific attention is the remarkable capacity of baboons to sustain intricate social relationships in their large troops of up to 150 members. The troops consist of a small number of males and eight or more matrilineal families of females and young. The dominance order among males fluctuates over short time periods, the authors observe, making male baboon existence stressful and competitive, for the chance to mate depends mainly on position in the hierarchy.

They describe an even more elaborate hierarchical structure among the females, and it is far more stable: the daughters of high-ranking females share their mothers’ status. Family loyalty among siblings and cousins is strong, to the extent that related baboons will help each other if attacked or molested by others. Female baboons therefore have to know who is related to whom, what level of the hierarchy the involved parties belong to, who can be attacked and who cannot—and this on the basis not just of appearance but of vocalizations heard at a distance.

In Botswana’s Okovango Delta, a difficult and often swampy terrain where they have done their research since the 1970s, Cheney and Seyfarth have set out to observe—and by a series of ingenious experiments, test—the mental processes of baboons as exhibited by their grasp of social complexity. They chose to study baboons because of the large groups in which the animals live, obliging them to deal with the problem of living among many other individuals all equally intent on finding food and reproducing, with the possibilities of competition this implies.

The ability of baboons to survive and reproduce depends crucially on social skills, Cheney and Seyfarth found, and that explains why they have evolved mental skills for “observing social life, computing social relations, and predicting other animals’ behavior.” Baboons are acutely and often anxiously sensitive to the posture, position, gaze direction, and intentions of other baboons. They monitor each other constantly, and are aware of changes in status and alliances. And all this is in addition to their awareness of the physical environment, food sources, dangers from predators, and other facts relevant to the task of survival in a relentlessly hostile world.

Thirty million years ago baboons shared a common ancestor with chimpanzees and humans, but thereafter the respective evolutionary paths diverged. Cheney and Seyfarth list the numerous resulting differences between the lineages, in particular arguing that what is distinctive about humans is their possession of a “theory of mind,” the ability to represent the mental states of others in their own minds, and to communicate responses to them. In comparison the mental life of baboons is vastly simpler and less flexible. But this also shows how complicated human mental life is.

Oddly, no comparable studies of chimpanzee abilities to monitor social relationships has yet been undertaken, so comparisons between baboons and chimps remain to be drawn. Chimpanzees make and use tools and baboons do not; that is a big difference; and perhaps because chimps live in far smaller and more changeable groups than humans they need less ability to grasp social complexity. So much is speculation, Cheney and Seyfarth write; but it is also an invitation to further inquiry. One thing is clear: whereas human self-importance once placed human beings outside nature, everything that has followed from research of the kind done by Jane Goodall and Cheney and Seyfarth makes it impossible to think in such terms any longer. This point should by now be a mere commonplace; yet there are many millions of people whose faith-based ways of viewing the world lead them to think otherwise.

This Issue

May 15, 2008