98% homosapien and 4-6 million years separated from humans.
Bonobo Sex and Society
The behavior of a close relative challenges assumptions about male supremacy in human evolution
Frans B. M. de Waal
At a juncture in history during which women are seeking equality with men, science arrives with a belated gift to the feminist movement. Male-biased evolutionary scenarios-- Man the Hunter, Man the Toolmaker and so on--are being challenged by the discovery that females play a central, perhaps even dominant, role in the social life of one of our nearest relatives. In the past few years many strands of knowledge have come together concerning a relatively unknown ape with an unorthodox repertoire of behavior: the bonobo.
The bonobo is one of the last large mammals to be found by science. The creature was discovered in 1929 in a Belgian colonial museum, far from its lush African habitat. A German anatomist, Ernst Schwarz, was scrutinizing a skull that had been ascribed to a juvenile chimpanzee because of its small size, when he realized that it belonged to an adult. Schwarz declared that he had stumbled on a new subspecies of chimpanzee. But soon the animal was assigned the status of an entirely distinct species within the same genus as the chimpanzee, Pan.
Bonobos, Left & Right
Primate Politics Heats Up Again as
Liberals & Conservatives Spindoctor Science
by Frans de Waal
Imagine that you’re a writer and you have decided to offer your readers a first-hand account of the politically correct primate, the idol of the left, known for its “gay” relations, female supremacy, and pacific life-style. Your focus is the bonobo: a relative of the chimpanzee, and genetically equally close to us as the chimpanzee. You go all the way to a place called the Democratic Republic of the Congo to see these darling apes frolic in their natural habitat, hoping to come back with new and exciting material.
Alas, you barely get to see any bonobos. You watch a few of them quietly sitting in the trees, eating nuts. That’s all. This is what happened to Ian Parker, who nevertheless managed to write thirteen pages of carefully crafted prose as a “far-flung correspondent” for The New Yorker. We learn about the “hot, soupy air,” the rainstorms, the mud streams, the sound of falling fruit shells, and his German host, Gottfried Hohmann, who is described as rather unsympathetic.1
The main message of Parker’s piece could of course have been that fieldwork is no picnic, but instead he went for profound revelation: bonobos are not nearly as nice and sexual as they have been made out to be. Given that the bonobo’s reputation has been a thorn in the side of homophobes as well as Hobbesians, the right-wing media jumped with delight. The bonobo “myth” could finally be put to rest. Parker’s piece was gleefully picked up by The Wall Street Journal and Dinesh D’Souza (yes, the same one who blamed 9/11 on the left), who accused “liberals” of having fashioned the bonobo into their mascot. D’Souza urged them to stick with the donkey.2
This might all have been amusing if it weren’t for the fact that these are not just political skirmishes. At issue is what we know. Parker presented his trip as a fact-finding mission that had unearthed revolutionary new insights. His message was that bonobos are killer apes, just like their cousins, the chimpanzees. The animal kingdom remained “red in tooth and claw,” as it ought to be.
Yet, the most striking cases of bonobo aggression that he reported have been known for decades, and actually didn’t come from the natural habitat, even less from first-hand observation by our brave explorer. A typical description was given by Jeroen Stevens, a Flemish biologist, of a gang of five bonobos assaulting a single victim at Apenheul Zoo, in the Netherlands. “They were gnawing on his toes. I’d already seen bonobos with digits missing, but I’d thought they would have been bitten off like a dog would bite. But they really chew. There was flesh between their teeth.”1
Many such cases have been documented at zoos over the years, and have actually led to changes in policies of how to keep bonobos. This is why I warned in Bonobo: The Forgotten Apenot to romanticize the species: “All animals are competitive by nature and cooperative only under specific circumstances.”3
The second part of Parker’s revisionist attempt was the suggestion that bonobo sexual tendencies have been grossly exaggerated. Since most observations of bonobo sex come from zoos, they can be safely ignored, we were told, on the assumption that captivity distorts behavior. The problem is, of course, the incongruity of considering zoo observations valid in relation to aggression, yet worthless in relation to sex. One either accepts both or rejects both.
Perhaps it is time to go over the evidence once again and see if bonobos are as special as they have been made out to be. Unfortunately, the evidence that we have is relatively old. The impression that there are new discoveries is merely a product of creative writing. The DRC is only now emerging from a bloody civil war that has kept field workers away. Knowledge about bonobos in their natural habitat has been at a virtual standstill for about a decade.
But there exists excellent field data from before this time. Combined with reports from captive apes, these provide a rather coherent picture. The most important fact, which has remained unchanged over the last three decades of bonobo research, is that there exist no confirmed reports of lethal aggression, neither from the field nor from captivity. For chimpanzees, in contrast, we have dozens of cases of adult males killing other males, of males killing infants, of females killing infants, and so on. This is in the wild. In captivity, I myself documented how two male chimpanzees brutally mutilated a third, castrating him in the process, which led to his death.4 There is absolutely no dearth of such information on chimpanzees, which contrasts greatly with the zero incidence in bonobos.
Reviewing chimpanzee violence in Demonic Males, Richard Wrangham went on to draw the following comparison with “the gentle ape,” the bonobo: “we can think of them as chimpanzees with a threefold path to peace. They have reduced the level of violence in relations between the sexes, in relations among males, and in relations between communities.”5
None of this is to say that bonobos live in a fairy tale. When first writing about their behavior, I spoke of “sex for peace” precisely because bonobos had plenty of conflicts. There would obviously be no need for peacemaking if they lived in perfect harmony. Sexual conflict resolution is typical of females, but also occurs among males: “Vernon regularly chased Kalind into the dry moat … After such incidents the two males had almost ten times as many intensive contacts as was normal for them. Vernon would rub his scrotum against Kalind’s buttocks, or Kalind would present his penis for masturbation.”6
It is entirely possible that one day we will discover serious, perhaps deadly aggression in this species, and it probably will be females collectively attacking a male, since this is the fiercest aggression seen at zoos (and a good argument against attributing female dominance to male “chivalry”). For now, however, bonobos offer the opposite picture. Whereas most observed chimpanzee killings occur during territorial disputes, bonobos engage in sex at their boundaries. They can be unfriendly to neighbors, but soon after a confrontation has begun, females have been seen rushing to the other side to copulate with males or mount other females. Since it is hard to have sex and wage war at the same time, the scene rapidly turns into socializing. It ends with adults from different groups grooming each other while their children play.
These reports go back to 1990, and come mainly from Takayoshi Kano, the Japanese scientist who worked the longest with wild bonobos.7,8 While writing Bonobo, I interviewed field workers, such as Kano and also Hohmann. Asking the latter how his bonobos react to another group, Hohmann replied: “It starts out very tense, with shouting and chasing, but then they settle down and there is female-female and male-female sex between members of the two communities. Grooming may occur, but remains tense and nervous.”9 This is not exactly the stuff expected of killer apes, although Hohmann did add that groups do not always mingle and that he never saw males from different groups groom.
Perhaps the bonobo’s peaceful image can be countered with descriptions of them catching and eating prey? Isn’t this violent behavior? Not really: feeding has very little to do with aggression. Already in the 1960s, Konrad Lorenz explained the difference between a cat hissing at another cat and a cat stalking a mouse. The neural circuitry of the two patterns is different: the first expresses fear and aggression, the second is motivated by hunger. Thus, herbivores are not any less aggressive than carnivores — as anyone who has been chased by a bull can attest. The fact that bonobos run after duikers and kill squirrels — which has been seen many times — is therefore best kept out of debates about aggression.
As for sex, I perceive the shyness of many scientists as a problem. It leads them to either ignore sexual behavior or call it something else. They will say that bonobos are “very affectionate,” when the apes in fact engage in behavior that, if shown in the human public sphere, would get you quickly arrested. Two females may be pressing vulvas and clitorises together, rapidly rubbing them sideways in a pattern known as genito-genital rubbing (or “hoka-hoka”), and Hohmann, who has seen this pattern many times, wonders: “But does it have anything to do with sex? Probably not. Of course, they use the genitals, but is it erotic behavior or a greeting gesture that is completely detached from sexual behavior?”1
Fortunately, a United States court settled this monumental issue in the Paula Jones case against President Bill Clinton. It clarified that the term “sex” includes any deliberate contact with the genitalia, anus, groin, breast, inner thigh, or buttocks. In short, when bonobos contact each other with their genitals (and squeal and show other signs of apparent orgasm), any sex therapist will tell you that they are “doing it.”10
Bonobos do it a lot, and not just between male and female. Nothing has changed in this regard. The only disagreement arose when Craig Stanford compared existing data in wild chimpanzees and bonobos. Stanford is an American primatologist who has studied chimpanzees but not bonobos, which may explain why he considered only adult heterosexual relations when claiming similar sex rates for both species.11 Since bonobos have sex in virtually all partner combinations, they were seriously short-changed by these calculations.
How much bonobos differ from chimpanzees was highlighted by a recent experiment on cooperation. Brian Hare and co-workers presented apes with a platform that they could pull close by working together. When food was placed on the platform, the bonobos clearly outperformed the chimpanzees in getting a hold of it. The presence of food normally induces rivalry, but the bonobos engaged in sexual contact, played together, and happily shared the food side by side. The chimpanzees, in contrast, were unable to overcome their competition.12 For two species to react so differently to the same experimental set-up leaves little doubt about a temperamental difference.
In another illustration, at a forested sanctuary at Kinshasa it was recently decided to merge two groups of bonobos that had lived separately, just so as to induce some activity. No one would ever dream of doing this with chimpanzees as the only possible outcome would be a blood bath. The bonobos produced an orgy instead.
In short, so long as we call sex “sex” and focus on known levels of intraspecific (as opposed to interspecific) violence, there is absolutely no reason to drop the claim that bonobos are relatively peaceful, and that sexual behavior serves a wide range of non-reproductive functions, including greeting, conflict resolution, and food sharing.
I understand the frustration of field workers with the image of bonobos as angels of peace, which is not only one-dimensional, but incorrect. On the other hand, anyone who objects to the occasional hyperbole (such as “chimpanzees are from Mars, bonobos are from Venus”), should realize that no one would ever have heard of the species — and no reporter would have considered them for a piece in The New Yorker — if they’d been described as merely affectionate. Possibly, one or two decades from now a new image of the bonobo will emerge, one more complex than what we have today. This is already happening thanks to detailed studies of their socio-ecology, observations that nuance the dynamics of female dominance, and video-analyses of their natural communication. No doubt, the return of bonobo field workers to Africa will significantly add to our knowledge.
But whatever we find out, a Hobbesian make-over of the bonobo is not to be expected any time soon. I just can’t see this ape go from being a gentle, sexy primate to a nasty, violent one. Japanese primatologist Takeshi Furuichi, perhaps the only scientist to have studied both chimpanzees and bonobos in the forest, said it best: “With bonobos everything is peaceful. When I see bonobos they seem to be enjoying their lives.”1
About the Author
Frans B. M. de Waal was trained as a zoologist and ethologist in the European tradition resulting in a Ph.D. in biology from the University of Utrecht, in 1977. In 1981, Dr. de Waal moved to the USA, first to Madison, Wisconsin, and now in a joint position in the Psychology Department of Emory University and at the Yerkes National Primate Research Center, both in Atlanta. He is known for his popular books, such as Chimpanzee Politics (1982), Peacemaking Among Primates (1989, which received the Los Angeles Times Book Award), Bonobo: The Forgotten Ape (1997), and his latest, Our Inner Ape (2006). His current interests include food-sharing, social reciprocity, and cultural transmission in primates as well as the origins of morality and justice in human society.
Bonobo communities are peace-loving and generally egalitarian. The strongest social bonds are those among females, although females also bond with males. The status of a male depends on the position of his mother, to whom he remains closely bonded for her entire life.
In chimpanzee groups the strongest bonds are established between the males in order to hunt and to protect their shared territory. The females live in overlapping home ranges within this territory but are not strongly bonded to other females or to any one male.
Gibbons establish monogamous, egalitarian relations, and one couple will maintain a territory to the exclusion of other pairs.
Human society is the most diverse among the primates. Males unite for cooperative ventures, whereas females also bond with those of their own sex. Monogamy, polygamy and polyandry are all in evidence.
The social organization of gorillas provides a clear example of polygamy. Usually a single male maintains a range for his family unit, which contains several females. The strongest bonds are those between the male and his females.
Orangutans live solitary lives with little bonding in evidence. Male orangutans are intolerant of one another. In his prime, a single male establishes a large territory, within which live several females. Each female has her own, separate home range.