News and Views

A View on the Science: PhysicalAnthropology at the Millennium

RICHARD W. WRANGHAMDepartment of AnthropologyHarvard UniversityCambridge, MA 02138

EDITOR’S NOTE The year 2000 marksthe onset of the 21st century. Physical an-thropologists will provide brief reflectionson our discipline, including what attractedthem to it, and their views on the directionsour discipline may pursue as we enter, in

January 2001, the third millennium. Am JPhys Anthropol 111:445–449, 2000.© 2000 Wiley-Liss, Inc.

THE OTHER APES; TIME FOR ACTION

New Year’s Day 2000, an excuse for mil-lennial thoughts. How soon will the old an-tagonisms of biology and culture turn to mu-tual respect, even to celebration? In time tohelp the other apes?

A lingering cartesianism

Consider a Martian visiting committee,reviewing anthropology’s progress afterits first hundred and fifty years. Theymight congratulate us on recognizing ourmorphological and evolutionary proximityto the apes, but wouldn’t they wonder atthe persisting anthropocentricity that sooften causes a false dichotomy between usand our cousins? As interplanetary biolo-gists, they would puzzle at the widespreadnotion that behavior which varies acrosshuman populations can’t have been influ-enced by genes, unlike other animals; or atthe fact that even though primatology’sraison d’etre is to shed light on humanity,most comparative primate studies excludedata on humans. Looking at the range ofearth’s species and their many differ-ences, they would surely be startled thatconventional anthropological wisdom of-ten deems human social structure infi-nitely variable, whereas all other speciesare granted their typical social forms. Not-ing the human pervasiveness of fission-fusion grouping and male-bonded commu-nities, patriarchy and war—a combinationstrikingly similar to traits among chim-panzees—they would be surprised that wedon’t yet have a unified theory of ape andhuman social evolution. And surely, theywould lament a species that allows itsnearest relatives to slide to extinctionwithout a determined howl at the tragedyof the loss.

Richard Wrangham is Professor of Anthropology atHarvard University. He is interested in the behavioralecology of primates, including humans and human an-cestors. He studied chimpanzee behavior in Gombe Na-tional Park (Tanzania), and in Kibale National Park(Uganda), where he has co-directed the Kibale Chim-panzee Project for research and conservation since1987, together with Dr. G. Isabiriye-Basuta. He re-ceived a MacArthur Foundation Fellowship (1987-1992), the Rivers Medal from the Royal AnthropologicalInstitute of Great Britain (1993), and a Fellowship inthe American Academy of Arts and Sciences (1993). In1996 he and Dale Peterson wrote Demonic Males: Apesand the Origins of Human Violence (Houghton Mifflin).

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 111:445–449 (2000)

© 2000 WILEY-LISS, INC.

The ultimate causes of social life:deductions from chimpanzee

soap operas

My path to appreciation of the apes beganat the age of 17, when on a whim I boughtS.A.Barnett’s edited collection, “A Centuryof Darwin,” and discovered the thrill of evo-lution’s explanatory power. Doubtless Ididn’t understand the arguments verydeeply, but they were wildly superior to ab-stract philosophy or religious cosmology. Idetermined to experience African wildlifeand then to major in zoology. I was lucky tofind a job—it paid a shilling a day—assist-ing a biologist in Zambia. John Hanks wasstudying the social system of waterbuck, aslow-moving antelope. For several months Iwatched habituated waterbuck, and it is tothose hot, bright, long, bush hours in mylate teens that I trace a lifelong interest inthe ultimate causes of social life. Plains an-imals are easy to study because their livesare so public. There were obvious lessonsabout how females moved to the fresh grass,while males strategized to stay with them.The evening talk was of Y33’s fight with RB,and where GL had creched her infant, andwhy the bachelors had crossed the river.The importance of individual strategies wasas clear as the primacy of females in thedesign of social life.

If this seems remote from anthropology, itwas. But student life at Oxford in the late1960s was full of wonderfully fundamentalideas about humans. Robert Ardrey, KonradLorenz, and Desmond Morris were the talkof the town because of their clear-eyed andprovocative biological narratives of humansocial behavior (Ardrey, 1961, 1966; Lorenz,1967; Morris, 1967). These authors sub-jected human aggression, mating, andfriendship to the same cool evolutionaryanalyses that biologists were beginning toapply to other animals. In doing so theycaptured the imagination of the public andforeshadowed the rise of a more serious be-havioral ecology.

Most professionals, admittedly, were notamused. These popularly written scenariosof human evolution were full of holes. Muchof their biology and anthropology was dubi-ous, and they had an alarming whiff of

genetic determinism. But there was inspira-tion in the vision of uniting paleoanthropol-ogy with studies of living animals, and for-tunately there was serious science availablein the University to balance the speculation.Niko Tinbergen and David Lack were teach-ing: Tinbergen, a founder of ethology (Tin-bergen, 1964), and Lack, the ecologist whoexplained bird mating systems in terms ofindividual food-finding (Lack, 1968). Iplanned a PhD in animal behavior, hopingto work with a diurnal social carnivore thatmight serve as a model for human ances-tors. Banded mongooses were a possibility.

But my plans changed overnight, whenmy advisor, Harold Pusey, told me that hisdaughter Anne was going to work with JaneGoodall, and suggested that I ask Goodallfor a job as a research assistant. She hap-pened to need help, so by sheer luck, the endof 1970 found me in Gombe observing chim-panzees. I hadn’t read a word about apes incollege, but I soon learned how wrong thecartesian barrier between humans andother animals feels. Every day in the com-pany of wild chimpanzees offered a sensethat anything might happen, from inventionto insight to understanding. The chimpan-zees had expressive emotional lives andstrong, clear, resonant personalities. Theirchanging relationships made a terrific dailysoap opera. Their interactions could involveseveral individuals and sometimes ap-peared to incorporate events over manydays. The complexity of alliances, grudges,and tenderness made this a dramaticallydifferent world from an antelope’s.

In 1970, observers were just beginning toconduct all-day observations on individualchimpanzees, and my job was to documentsibling relationships. It was immediatelyapparent that the mood and activity level ofthe day would be dictated by the sex andstatus of the individual I was observing.While the mothers were relatively seden-tary and reserved, the males were boister-ous and gregarious. At the same time, thesocial lives of both sexes were strongly in-fluenced by the changing seasons of fruitproduction. Thrilled at the chance to exploresuch fundamental issues, I planned a studyof seasonal variation in female behavior. Iwas talked out of it, however, because fe-

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males vary so much in their reproductivestates that extrinsic influences would be rel-atively hard to detect. So I worked on thesame question with males instead, and itwould be twenty years before I returned tothe questions about females; questions Istill pursue.

Apes: anthropology’s luck

My transforming journey into the world ofwild chimpanzees was unplanned and unde-served. I think of it as a private metaphorfor a parallel piece of luck for anthropology.It’s not merely that we have three particu-larly close ape relatives—gorillas, chimpan-zees, and bonobos—but also that these spe-cies have apparently evolved rather little inthe last five to ten million years. They havechanged much less than we have, for exam-ple. It didn’t have to happen that way. Ourown species might easily have been morelike coelacanths, isolated members of a deeptaxon with no relatives sufficiently close tosay much about our pre-history. Or we couldhave had a bevy of close kin who had di-verged so much from each other that none ofthem was informative about our ancestors.But by happy chance, the living Africanapes are so fundamentally similar to eachother in their biology and morphology thatthey portray a clear common heritage: theape essence on which our subsequent pre-human existence was built. Even more thanDarwin or anyone else realized until re-cently, this means that we can use the livingapes to reconstruct our ape past, to thinkabout why we diverged, and to considerwhat we were like as we did so (Pilbeam,1996).

However, we can’t reconstruct our ances-tors simply by virtue of features held incommon between apes and humans, be-cause many traits vary among living apes.For example, the only two species of mam-mals in which males are known to live withtheir relatives, and occasionally launch le-thal raids on neighboring groups, are hu-mans and chimpanzees. Whether our com-mon ancestor shared the habit of lethalraiding, or which other ancestors did so, willremain uncertain until we understand whylethal raiding is favored (or not) in livingspecies (Wrangham, 1999). The same ap-

plies to other features shared between hu-mans and apes, such as hunting, or a richset of behavioral traditions, or learnedstyles of communication, or an incipient the-ory of mind (Hare et al., in press; Marshallet al., 1999; McGrew, 1992; Stanford, 1998;Whiten et al., 1999). So the differencesamong the three African apes are highlyinformative, because they are large enoughto provide specific ideas about the ecologicaland social pressures that shaped the surviv-ing species from a single ancestor. Theseideas can be tested by studies of the livingapes, using different habitats to provide dif-ferent selection pressures. Our search forthe sources of our own existence is madeenormously easier by the happenstance thatfour other great apes are still alive.

Humans versus apes: the contrastbetween intellectual interest and

species survival

Each year thousands of African apes arekilled for the pot, and hundreds of orangu-tans die in the service of the pet trade (Bo-wen-Jones and Pendry, 1999; Wilkie et al.,1992). The ape range countries have theworld’s highest rates of human populationgrowth and of forest loss, so it’s not surpris-ing that a litany of problems affects even thebest-protected sites, which are those withlongterm research. To take a few currentexamples, Indonesian orangutans in Tan-jung Puting, Gunung Palung, and Ketambeare all under immediate threat from log-ging, and a population newly found to usetools in north Sumatra seems likely to bealready extinct (Rijksen and Meijaard, inpress; C. van Schaik, pers. comm.). Sevenhabituated groups of gorillas in the Demo-cratic Republic of the Congo’s Kahuzi-Biegawere slaughtered during military conflictlast year (J. Yamagiwa pers. comm.), justlike the many gorillas converted to food forlogging crews and middle-class restaurantsin central Africa. Snaring has begun inGombe, where Goodall considers the chim-panzees too few and isolated to survive forlong. Several populations of the newly pro-posed Nigerian subspecies of chimpanzees,P.t. vellerosus, are apparently already ex-tinct in the wild, less than a decade afterbeing documented. In the Ivory Coast,

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poaching, logging, and human diseases arefast reducing the population of Taı’s nut-cracking chimpanzees. Bonobos live only inthe Democratic Republic of the Congo, anddon’t look safe anywhere. Even in Wamba,where bonobos have been studied since 1974and there used to be a food taboo, they livein a forest newly depleted of other largemammals, and have themselves been thetargets of hunters since 1994. Orangutansand bonobos, each with just a few thousandindividuals worldwide, will presumably gofirst. Within a few decades gorillas, perhaps100,000 now, will be lucky to have anystrongholds. Chimpanzees, now twice as nu-merous as gorillas, will last the longest. Buteven merely stabilizing the rate of loss willtake a massively increased effort that com-bines education, resources, and imagina-tion. Weighed down by their very slow ratesof reproduction, their needs for large areasto live in, their conflicts with humans overland, and their popularity as food and pets,the great apes can’t hope to survive withoutserious help from their kin (Peterson andGoodall, 1993).

The need for a planetary action plan

So three tasks loom, each one supportingthe other two.

First, anthropologists can extol the greatapes to the policy-makers—whether to vot-ers or presidents, NGOs or governments,range countries or international institu-tions. We can help end the debates overwhether it’s culturally legitimate to eatgreat apes, or whether it’s right to give greatapes conservation priority over other mam-mals. We shouldn’t eat apes, and we shouldgive them special attention.

Second, we can encourage new field stud-ies. Even if most of the extant populationswill be gone within a few short decades,those being studied will last the longest,because researchers keep monitors in thefield and enlarge the constituency of inter-est and support.

Third, there is much to be learned beforethe opportunities evaporate. Great apeshave been studied in the wild for 40 years,less than a chimpanzee lifetime. There arewhole subspecies still essentially untouched:neither western gorillas nor central chim-

panzees has yet had a population habitu-ated in the wild. We have only the mostelementary understanding of their ecology(such as why gorillas grow faster than chim-panzees), cognitive abilities (such as themeanings of their calls), reproductive strat-egies (such as what they know about pater-nity), cultures (such as whether traditionsinclude social rules), parental influence(such as how much teaching occurs), orwhat they understand about each other (theextent of their theory of mind). Our expla-nations for their societies still hold hugegaps (such as why male orangutans don’tcommit infanticide, and why females toler-ate forced copulations; or why extra-commu-nity copulations are favored among chim-panzees, and why males sometimes killneighboring females; or why bonobos don’thunt monkeys, or are always as peaceful asthey seem). Non-invasive studies of genes,diseases, hormones, diet, and nutritionalstatus are opening new directions. We havebarely begun to attempt an integrated the-ory of ape social adaptations, or to under-stand how human relationships can be an-alyzed in similar ways to the apes, or tothink seriously about how ape social lifebecame transformed into human cultures.We have largely accepted our physical evo-lution from apes, but we have yet to accom-modate the reality of our ape biology for oursocial world. Our visiting committee wouldsurely raise some Martian eyebrows.

Humans are mammals, primates, ca-tarrhines, and great apes. We can relish thespecies that most closely share the dawningof our consciousness, or we can let them go.While we’re pondering, the forests are fall-ing and the apes are dying. It’s up to evolu-tionary anthropologists, as much as anyone,to take the battle to the halls of government.Let us be bold. There’s an internationalagreement not to hunt whales and dolphins.Why not an equivalent for the great apes?Can we persuade the United Nations tomake the great apes the first World Heri-tage Species?

It’s time for a planetary agreement to pro-tect and cherish the great apes. The soonerwe get it, the more it will be worth. Everyday counts.

448 R.W. WRANGHAM

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