Bonobo Bliss

Evidence that doing good feels good.

Humans may not know exactly what a bonobo facial expression means, but it would be hard not to feel a connection with this adult male.

Jutta Hof

Excerpted from The Bonobo and the Atheist: In Search of Humanism among the Primates, by Frans de Waal. Copyright © 2013 by Frans de Waal. With permission of the publisher, W.W. Norton & Company, Inc.

Photographs in this article are by Jutta Hof from her book, Menschenaffen Wie Wir/Apes Like Us (German/English) with text by evolutionary anthropologist Volker Sommer.

Amos was one of the handsomest males I have known, except perhaps on the day he stuffed two entire apples in his mouth, which taught me again that chimpanzees can do things we can’t. He had large eyes in a friendly, symmetrical face, a full, shiny coat of black hair, and well-defined muscles on his arms and legs. He was never overly aggressive, as some males can be, yet he was supremely self-confident during his heyday. Amos was beloved. Some of us cried at the time when he died, and his fellow apes were eerily silent for days. Their appetites took a hit.

At the time, we didn’t know what his problem was, but we learned postmortem that in addition to a hugely enlarged liver that took up most of his abdomen, he had several cancerous growths. He had lost 15 percent of his weight from a year before, but even though his condition must have been building for years, he had acted normally until his body just couldn’t hold out any longer. Amos must have felt miserable for months, but any sign of vulnerability would have meant loss of status. Chimps seem to realize this. A limping male in the wild was seen to isolate himself for weeks to nurse his injuries, yet would show up now and then in the midst of his community to give a charging display full of vigor and strength, after which he’d withdraw again. That way, no one would get any ideas.

Amos didn’t betray his condition until the day before his death, when we found him panting at a rate of sixty breaths per minute, with sweat pouring from his face, sitting on a burlap sack in one of the night cages while the other chimps were outside in the sun. Amos refused to go out, so we kept him separate until a veterinarian could take a closer look. The other chimps kept returning indoors to check on him, though, so we cracked open the door behind which Amos sat to permit contact. Amos placed himself right next to the opening, and a female, Daisy, gently took his head to groom the soft spot behind his ears. Then she started pushing large amounts of excelsior through the crack. This is a wood shaving that chimps love to build nests with. They arrange it all around them and sleep on it. After Daisy had given Amos the wood wool, we saw a male do the same. Since Amos was sitting with his back against the wall and not doing much with the excelsior, Daisy reached in several times to stuff it between his back and the wall.

This was remarkable. Didn’t it suggest that Daisy realized that Amos must be uncomfortable and that he would be better off leaning against something soft, similar to the way we arrange pillows behind a patient in the hospital? Daisy probably extrapolated from how she feels leaning against excelsior, and indeed, she is known among us as an “excelsior maniac” (instead of sharing the stuff, she normally hogs it).

The next day, Amos was put to sleep. There was no hope for survival, only the certainty of more pain. This incident, at the Field Station of the Yerkes National Primate Research Center, near Atlanta, Georgia, illustrates two contrasting sides of chimpanzee social life. First, these primates live in a cutthroat world, which forces a male to conceal physical impairment for as long as possible in order to keep up a tough façade. But second, they are part of a tight community, in which they can count on affection and assistance from others, including nonrelatives. Popular writers prefer to simplify things by describing the lives of chimpanzees either in Hobbesian terms, as nasty and brutish, or by stressing their friendly side, but in fact it’s not one or the other. It’s both. If people ask how chimpanzees can possibly be called empathic, knowing that they sometimes kill one another, my return question is always whether by the same token we shouldn’t abandon the whole notion of human empathy as well.

This duality is crucial. Morality would be superfluous if we were universally nice. What would there be to worry about if all that humans ever did was show sympathy for one another, and never steal, never stab someone in the back, never covet another’s wife? This is clearly not how we are, and it explains the need for moral rules. On the other hand, we could design a zillion rules to promote respect and care for others, but they’d come to naught if we didn’t already lean in that direction.

Bonobos express concern for others following conflict by grooming and licking any (usually minor) injuries that they have caused.

Jutta Hof

Morality is a system of rules concerning the two H’s of Helping or at least not Hurting fellow human beings. It addresses the well-being of others and puts the community before the individual. It does not deny self-interest, yet curbs its pursuit so as to promote a cooperative society.

This functional definition sets morality apart from customs and habits, such as eating with knife and fork versus chopsticks or one’s bare hands. People may disapprove of my eating with my hands, at least in my current culture, but their disapproval is not of a moral nature. Even young children distinguish etiquette (boys go to the boys’ toilet and girls to the girls’ toilet) from moral rules (don’t pull ponytails). Rules related to the two H’s are taken far more seriously than conventions. Toddlers believe in the universality of the former. If you ask them whether they can imagine a culture where everyone goes to the same toilet, they can, but ask them whether there may be cultures where it is perfectly fine to hurt someone else unnecessarily, and they refuse to believe so. As the philosopher Jesse Prinz has explained, “Moral rules are directly grounded in the emotions. When we think about hitting, it makes us feel bad, and we cannot simply turn that feeling off.” Moral understanding develops astonishingly early in life. Infants under one year of age already favor the good guy in a puppet show. The puppet who nicely rolls a ball back and forth with another is preferred over one who steals the ball and runs off with it.

Empathy is critical. At a young age, the child learns that slapping or biting a sibling produces a screaming reaction with a range of negative consequences. Apart from those few children who will grow into psychopaths—whose childhood is marked by animal torture, excessive violence, and lack of remorse—the vast majority don’t enjoy the sight of a crying sibling. Second, hurting your sibling brings all fun and games to an abrupt halt. No one wants to play with someone who lashes out all the time. Finally, an angry parent or teacher is likely to enter the scene and yell at the hitter, or make him or her feel guilty by pointing out the victim’s tears. All of these emotional consequences discourage hurting a playmate and encourage empathy, teaching children to take the feelings of others seriously.

Not that we should be surprised by such early development. If we are surprised, it is only because some have believed that goodness is not part of human nature, and that we therefore need to work hard to instill it in our children. In that view, children are selfish monsters, who learn to be moral from teachers and parents despite their natural inclinations. They are reluctant moralists. My view is the exact opposite. The child is a natural moralist, one that gets a huge helping hand from its biological makeup. We humans automatically pay attention to others, are attracted to them, and imagine their situation as our own. Like all primates, we are emotionally affected by others.

Darwin speculated that morality grew straight out of animal social instincts, saying that “it would be absurd to speak of these instincts as having been developed from selfishness.” Darwin saw the potential for genuine altruism, at least at the psychological level. As do most biologists today, he drew a sharp line between the process of natural selection, which indeed has nothing nice about it, and its many products, which cover a wide range of tendencies. He disagreed that a nasty process ipso facto needs to produce nasty results. To think so is what I have dubbed the “Beethoven error,” since it is like evaluating Ludwig van Beethoven’s music on the basis of how and where it was composed. The maestro’s Viennese apartment was a messy, smelly pigsty, strewn with waste and unemptied chamber pots. Of course, no one judges Beethoven’s music by it. In the same way, even if genetic evolution proceeds through death and destruction, this doesn’t taint the marvels it has produced.

Science tells us that we breathe in order to supply our bodies with oxygen. Lacking this knowledge, however, I’d still do exactly the same, like billions of humans and animals before me. Awareness of O2 is not what drives breathing. Similarly, when biologists speculate that altruism evolved for its payoffs, it doesn’t mean that actors need to know about this. Most animals don’t think ahead, as in “If I do this for him, he may return the favor tomorrow.” Lacking foresight, they just follow a benevolent impulse. The same applies to humans. Except in business or between unacquainted people, humans rarely tally up the costs and benefits of their behavior, especially among friends and family. In fact, doing so is a bad sign, which family therapists use as an indicator that a marriage is on the rocks.

Both human and animal altruism may be genuine, therefore, in that it lacks ulterior motives. This is true to the point that we have trouble suppressing it. James K. Rilling, an Emory University anthropologist colleague of mine, concluded from neuroimaging experiments that we have “emotional biases toward cooperation that can only be overcome with effortful cognitive control.” Think about it: this means that our first impulse is to trust and assist; only secondarily do we weigh the option of not doing so, for which we need reasons. This is the exact opposite of being driven by incentives. Only psychopaths lack this natural impulse. Rilling further showed that when normal people aid others, areas in the brain associated with reward are activated. Doing good feels good.

This “warm glow” effect brings a touching image to mind that I have seen countless times while working with rhesus monkeys. The behavior in question was not exactly altruistic, but very close to the source of all mammalian nurturance. Every spring, our zoo troops produced dozens of newborns. The babies held magnetic appeal for juvenile females, which would try to get their little hands on them by patiently grooming their mothers. It would take a long time of hanging around the mother until the baby would be released to take a few wobbly steps toward the would-be sitter. She’d pick it up, carry it around, turn it upside down to inspect its genitals, lick its face, groom it from all sides, but eventually doze off with the baby firmly clutched in her arms. We took bets on how long it would take. Five minutes, ten minutes? The sleepiness that overcame the babysitters gave the impression that they were in a trance, or perhaps ecstatic, having waited so long for their lucky break. As they held their treasure, release of oxytocin, known as the hormone of love, in their bloodstream and brain weighed down their eyelids. Their sleep would never last long, though, and soon they’d return the baby to its mother.

An older bonobo offspring follows how its mother carefully grooms the face of her infant. Such joint attention is common in the species

Jutta Hof

The joy of baby care prepares young females for the most altruistic act of all. Mammalian maternal care is the costliest, longest-lasting investment in other beings known in nature, starting with nourishment of the fetus and ending many years later. Or, as most parents would say, never. Strangely enough, however, maternal care has been largely absent from the altruism debate. Some scientists don’t even want to count it as altruism, since it doesn’t fit their emphasis on sacrifice. They want to speak of altruism only if it harms the performer, at least in the short run. No one should be eager to be an altruist, let alone take pleasure in it. I call this the altruism-hurts hypothesis, which is deeply erroneous. After all, the definition of altruism is not that it needs to cause pain, only that it carries a cost.

If maternal care was almost too obvious for theoreticians to consider, it is also the most self-rewarding care, which brings me to the altruism-feels-good hypothesis. Invariably, nature associates things that we need to do with pleasure. Since we need to eat, the smell of food makes us drool like Pavlov’s dogs, and food consumption is a favorite activity. We need to reproduce, so sex is both an obsession and a joy. And to make sure we raise our young, nature gave us attachments, none of which exceeds that between mother and offspring. Like any other mammal, we are totally programmed for this in body and mind. As a result, we barely notice the daily efforts on behalf of our progeny and joke about the arm and leg that it costs. Distant relatives and nonrelatives obviously recruit less help, but the underlying satisfaction remains the same—an insight already present in the Meditations of the second-century Roman emperor Marcus Aurelius (“. . . acts that are consistent with nature, like helping others, are their own reward”). We are group animals, who rely on each other, need each other, and therefore take pleasure in helping and sharing.

Imagine you’re a writer, and you have decided to offer your readers a firsthand account of the politically correct primate, the idol of the left, known for its “gay” relations, female supremacy, and pacific lifestyle. Your focus is the bonobo: a close relation of the chimpanzee. You travel all the way to a place ironically called the Democratic Republic of the Congo (DRC) to see these darling apes frolic in their natural habitat, hoping to come back with new and exciting stories.

Alas, you barely get to see any bonobos. You watch a few of them quietly sitting in the trees, eating nuts. That’s all. Nevertheless The New Yorker managed to publish thirteen pages of carefully crafted prose from which we learn about the “hot, soupy air,” the rainstorms, the mud streams, the sound of falling fruit shells. Its main message could of course have been that fieldwork is no picnic, but instead the piece claimed that bonobos were not nearly as nice and erotic as people think. Given that this ape’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, and nature remain red in tooth and claw. The conservative commentator Dinesh D’Souza accused “liberals” of having fashioned the bonobo into their mascot, and he urged them to stick with the donkey.

Bonobos are among the most playful primates, and have a special laughing expression, known as the “play face,” exhibited here by the bonobo at left.

Jutta Hof

This might all have been amusing if it hadn’t been for the fact that these are not just political skirmishes. At issue is what we know. That bonobos can be aggressive is not in doubt. We know of fierce group attacks, mostly by females against males. Many such cases have been documented at zoos over the years, and have actually led to changes in how bonobos are kept. Since separation of mothers and sons disrupts a protective bond, zoos are increasingly keeping them together. As I warned in my 1997 book Bonobo: The Forgotten Ape, “All animals are competitive by nature and cooperative only under specific circumstances.”

With regard to bonobo behavior in the field, there are few new discoveries. The DRC has only recently emerged from a bloody civil war that killed an estimated 5 million people—an atrocious situation that has not been conducive to primatological research. Knowledge about wild bonobos has been at a virtual standstill for over a decade. We have excellent field data from before that time, however. The most important observation, which has remained unchanged over the last three decades, is that there are no confirmed reports of lethal aggression among bonobos. 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 male chimpanzees brutally mutilating and castrating a political rival, which led to his death. There is absolutely no dearth of such information on chimpanzees, which contrasts sharply with the zero incidence in bonobos.

Reviewing the violence of chimpanzees in Demonic Males, Harvard anthropologist Richard Wrangham went on to give the following characterization of bonobos: “. . . 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.” None of this is to say that bonobos live in a fairy tale. They engage in “sex for peace” precisely because they have plenty of conflicts. What would be the point of peacemaking if they lived in perfect harmony? Sexual conflict resolution typically occurs among females, but also among males, such as at the San Diego Zoo:

Vernon regularly chased Kalind into the dry moat. . . . After such incidents the two males had almost ten times as many intensive contacts as normal for them. Vernon would rub his scrotum against Kalind’s buttocks, or Kalind would present his penis for masturbation.

The contrast with their fellow species is striking. Most observed chimp killings take place during territorial disputes, whereas 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 of Kyoto University, the Japanese scientist who worked the longest with wild bonobos. Writing Bonobo, I interviewed field researchers, such as Kano and Gottfried Hohmann, a primatologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. When I asked the latter how his bonobos react to other groups, 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.” This is not exactly the stuff associated with killer apes, although Hohmann did add that communities do not always mingle and that males from different groups don’t groom each other.

At a sanctuary near Kinshasa, it was recently decided to merge two bonobo groups that had lived separately, just so as to create some activity. No one would ever dream of doing such a thing with chimpanzees, because the only possible outcome would be violence. It is well known at zoos that chimpanzee strangers need to be kept apart at all costs until they have become acquainted; otherwise one may be facing a bloodbath. The bonobos at the sanctuary, however, produced an orgy instead. They mixed freely, turning potential enemies into friends. To top it all off, there are the observations by Isabel Behncke, a Chilean primatologist working toward her PhD at Oxford University. She studies bonobo play behavior at Wamba, the site where Kano and other Japanese scientists have worked for decades. Behncke couldn’t believe her eyes when she saw individuals of different groups play together. She recently showed me videos taken in dense forest of an adult male surrounded by juveniles from a neighboring group, who were poking him, climbing on top of him, and dangling around him. It was all in fun, without a grain of danger or hostility. She also showed a game between a male and a female from an outside group, in which the female followed the male and grasped his testicles while both of them ran around and around a tree, again without any obvious tension. A bit of a playful character herself, Behncke joked that this is where the expression “holding him by the balls” must derive from.

Part of the confusion about aggressiveness of bonobos comes from their predatory behavior. While not on the scale of that of chimps, it is well developed. Bonobos kill small game, such as duikers (forest antelopes), squirrels, and immature monkeys, and sometimes hunt in groups. The problem is that this has little to do with aggressiveness. Already in the 1960s, the Austrian ethologist Konrad Lorenz warned that a cat hissing at another cat is not the same as a cat stalking a mouse. The first expresses a mixture of fear and aggression, the second is motivated by hunger. We know now that the neural circuitry is different. This is why Lorenz defined aggression as within-species behavior, and why herbivores are not considered any less aggressive than carnivores—as anyone who has witnessed a stallion fight can attest.

Confusing predation with aggression is an old error that recalls the time when humans were seen as incorrigible murderers on the basis of evidence that our ancestors ate meat. This “killer ape” notion gained such traction that the opening scene of Stanley Kubrick’s movie 2001: A Space Odyssey showed one hominin (a member of our ancestral branch that split off from that of the chimpanzees) bludgeoning another with a zebra femur, after which the weapon, flung triumphantly into the air, turned into an orbiting spacecraft. A stirring image, but based on a single puncture wound in the fossilized skull of an ancestral infant, known as the Taung Child. Its discoverer had concluded that our ancestors must have been carnivorous cannibals, an idea that the journalist Robert Ardrey repackaged in African Genesis by saying that we are risen apes rather than fallen angels. It is now considered likely, however, that the Taung Child had merely fallen prey to a leopard or an eagle.

Glorification of violence stands in contrast to our coyness about sex, which has led scientists either to ignore sexual behavior or to label it something else. In the same way that we prefer euphemisms—calling a toilet a “restroom,” or the unintended exposure of a nipple a “wardrobe malfunction”—the literature customarily calls bonobos “very affectionate,” while in fact referring to behavior that, if conducted in the human public sphere, would promptly get you arrested. Two females may be pressing their swollen genitals together, rapidly rubbing them laterally in a pattern known as genito-genital rubbing, but 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?”

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. We may quibble with this definition, but when bonobos stimulate each other by grabbing testicles, fingering clitorises, or rubbing genitals together while squealing and showing other signs of apparent orgasm, any sex therapist will tell you that they are “doing it.” I am thinking here of Susan Block, an American therapist who teaches “The Bonobo Way of Peace through Pleasure,” which seems an appropriate slogan, given that, apart from our own species, no other animal is as much into sex as the bonobo.

How dramatically bonobos differ from chimpanzees was highlighted by a recent experiment on cooperation. Evolutionary anthropologist Brian Hare and coworkers at the Duke Institute for Brain Sciences in Durham, North Carolina, presented apes with a platform that, by working together, they could pull close. When food was placed on it, the bonobos outperformed the chimpanzees. 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, by contrast, had trouble overcoming their competitiveness. For two species to react so differently to the exact same setup leaves little doubt about a temperamental difference.

Female bonobo at the Frankfurt Zoo with her offspring: The species often walks bipedally for brief periods.

Jutta Hof

Another piece of evidence comes from a comparison of ape orphans by Vanessa Woods, Hare’s wife and part of his team at Duke. Sadly, both chimps and bonobos are frequent victims of bushmeat hunting in Africa. Adults are typically sold as meat, whereas infants often end up in sanctuaries where humans lovingly care for them until they are strong enough to fend for themselves. Woods made a detailed comparison of infants of both species and found that bonobo infants engage in sexual contact at moments of excitement, such as when they are being fed, whereas chimp infants don’t. The species difference therefore shows up extremely early in life.

In short, so long as we dare to call sex “sex” and focus on known levels of within- species (as opposed to between-species) violence, there remains strong support for the claim that bonobos are relatively peaceful and that sexual behavior serves nonreproductive functions, including greeting, conflict resolution, and food sharing. The occasional hyperbole (for example, “chimpanzees are from Mars, bonobos are from Venus”) may be going too far, but no one would ever have heard of the species had it been described as merely affectionate. Whatever we find out in the years to come, with bonobo researchers returning to Africa to do fieldwork, a Hobbesian makeover of the species is not to be expected anytime soon. I just can’t see this ape going from being a gentle, sexy primate to a nasty, violent one. The only scientist who has extensively studied both chimpanzees and bonobos in the forest, the Japanese primatologist Takeshi Furuichi of Kyoto University, said it best: “With bonobos everything is peaceful. When I see bonobos, they seem to be enjoying their lives.”