Are humans more like chimpanzees or bonobos? (Personally, I'd rather be a bonobo than a human.)

SPIEGEL INTERVIEW: THE TWO APES WITHIN US
Hippy Sex Fiends and Brutal Machiavellians
So if humans evolved from apes, which ones are our closest relatives? Dutch primate researcher Frans de Waal spoke with SPIEGEL about bloodthirsty chimpanzees, sex-crazed bonobos, the origin of the family and the nature of human beings.

The Dutch zoologist Frans de Waal, 57, has been researching the behavior of primates since the beginning of the 1970s. Dozens of chimpanzees and bonobos in the Arnheim zoo in Holland and the San Diego zoo know him almost as well as their own clan mates. De Waal now leads the Living Links Center in the Yerkes National Primate Research Center at Emory University in Atlanta. The Center has some 3,400 primates including around 100 chimps. He is the author of "Our Inner Ape," published in 2005 and co- author of "Primates and Philosophers: How Morality Evolved," which will appear in September.

SPIEGEL: Mr. de Waal, if you were a member of the group of chimpanzees here beneath your observation tower, would you be the alpha male?

De Waal: (laughs) Absolutely not! My rank would be far lower. I'm not even allowed to enter the enclosure. The chimpanzees could tear me apart in no time. They're many times stronger than we are.

SPIEGEL: Let's assume you had the necessary strength.

De Waal: I would still run into all kinds of problems with the pecking order. It's like working for a company, where there are intrigues and where you have to do favors for friends and form networks. When it comes to social interaction, the chimpanzees appear to be just as intelligent as we are.

SPIEGEL: And who manages to fight his way to the top among the chimpanzees? The cleverest one? The biggest one?

De Waal: Not necessarily. We have two leaders in our group here, for example. One is a very relaxed, large male chimpanzee, which makes him popular with the females. The other one is a little guy who is extremely tenacious and uses dirty tricks when he fights, but he is detested by the females.

SPIEGEL: How do the leaders show their subjects that they're in charge?

De Waal: By putting on a big show. There is a male chimpanzee in Tanzania's Mahale Mountains who likes to make a huge to-do about throwing boulders into a dry riverbed. Each time he does it a large audience gathers and shows their deference. The chimpanzees bow and chatter, both typical submissive behaviors.

SPIEGEL: So they're perfect subjects?

De Waal: Not at all! There's plenty of intrigue going on beneath the surface. To help each other acquire power, chimpanzees form alliances based on giving and taking. It's the same thing with people. For example, unless US President George W. Bush doesn't give (British Prime Minister) Tony Blair, his biggest supporter, something significant soon, Blair will probably eventually withdraw his support for Bush.

SPIEGEL: You mean that the power game Blair and Bush are playing is essentially ape behavior?

De Waal: I'm convinced that that's the case. In people it starts already in childhood. If you put a group of two-year-olds in a room together, they quickly figure out who's the boss -- using fists, if necessary.

SPIEGEL: You claim in your book that a clear chain of command is superior to democratic decision-making. But couldn't such argumentation be used to justify a dictatorship?

De Waal: Hierarchies are unavoidable, but they're not the same as despotism. It's interesting that those human endeavors that depend most heavily on cooperation, armies or large companies, for example, have the most strongly developed hierarchies.

SPIEGEL: But clear hierarchies alone apparently aren't enough. Chimpanzees don't have armies, nor have they subjugated the world.

De Waal: No, armies are a purely human invention. Most soldiers who go to war nowadays don't even do it because they're inherently aggressive. Many American GIs in Iraq are poor kids who are only waging war because a couple of guys in Washington decided to send them to war. The guys in Washington, for their part, do it for territorial reasons. That brings us back to the chimpanzees, which also exhibit territorial behavior.

SPIEGEL: Primatologist Jane Goodall has said: "If chimpanzees had guns and knives and knew what to do with them, they would use them the way people do." Apes tear out their enemies' fingernails, crush their testicles and rip out their windpipes.

De Waal: Oh yes, they can be very brutal. Wild groups of chimpanzees attack their enemies like gangs. What they completely lack, precisely because of their strong territorial behavior, is a friendly relationship with their neighbors.

SPIEGEL: This, of course, is different in human beings. We trade with our neighbors, travel through their territory and help each other when disaster strikes.

De Waal: Exactly. And because of such traits, we cannot use the chimpanzee alone to explain why we are the way we are. For example, we can learn nothing from chimpanzees about our ability to make peace with other groups or nations. For that it's worth taking a closer look at the bonobo...

SPIEGEL: ...which is just as closely related to us as the chimpanzee.

De Waal: Yes. In fact, with its relatively small head and its frequently upright way of walking, it even bears a closer resemblance to us. Most importantly, however, the bonobos are remarkably peaceful in their interactions with one another.

SPIEGEL: What makes them such pacifists?

De Waal: Wild bonobos live in a habitat that is more bountiful. Unlike chimpanzees, they have more than enough to eat, so that female bonobos can travel in groups. They form coalitions, help each other and defend themselves to avoid being dominated by the males.

SPIEGEL: A matriarchy?

De Waal: Yes, but not one in which individual females are dominant. Instead, the entire group is dominant, with the older female bonobos generally in charge within that group.

SPIEGEL: Is it this female dominance that makes the bonobos so gentle by nature?

De Waal: Female bonobos at least appear to be good at keeping the peace. After all, it isn't especially worthwhile to them to constantly fight over their rank within the hierarchy, because rank has little impact on reproductive success. Although high-ranking female bonobos have better access to food for their young, this advantage is minimal compared to the benefits high-ranking male chimpanzees enjoy. For them, dominance translates directly into more offspring -- which explains their frequently brutal competition.

SPIEGEL: Does this mean that armchair psychologists got it right after all, that men are from Mars and women, the peacemakers, are from Venus?

De Waal: Wait a minute. I said that female bonobos keep the peace. The males are better at making peace.

SPIEGEL: What do you mean?

De Waal: Females avoid conflict. They are afraid of violence. The males, on the other hand, are less averse to strife. But once conflict breaks out, the males are much better at reconciling. In a study done in Finland, children who had quarreled were asked how much longer they intended to be angry at one another. The boys proudly said: "Oh, at least one or two days." The girls said...

SPIEGEL: Let's take a guess: "forever?"

De Waal: (laughs) Exactly.

SPIEGEL: And how do bonobo males fare in this peaceable, female-dominated society?

De Waal: Not badly. They have far less stress, which allows them to live longer -- and healthier -- lives than male chimpanzees. Nevertheless, most men probably wouldn't want to live the lives of bonobos. They're constantly clinging to their mothers' apron strings. They lack the ability to make decisions about their own fates, something that we and male chimpanzees practically consider our birthright.

SPIEGEL: Make love, not war. Bonobos are famous for their uninhibited sex. How important is it for their social order?

De Waal: Very important. Bonobos have sex about seven times more frequently than chimpanzees. But their encounters are also shorter, lasting 14 seconds on average. For them, sex is like shaking hands, and they do in all kinds of positions. These Kama Sutra primates stimulate each other orally and with their hands, and they even have sex hanging upside down. Most importantly, however, they engage in all kinds of combinations, homosexual or heterosexual. They do avoid sex between mothers and sons, however. Unlike chimpanzees, they also have sex when bonobo females aren't even in heat. I would say that three-quarters of their sexual activity isn't for reproductive purposes.

SPIEGEL: For what, then?

De Waal: For pleasure and relaxation. And for repairing damaged relationships. When bonobos climb a fruit tree, the first thing that happens is that the females have plenty of sex. Their so-called GG rubbing, or rubbing their genitalia together, is the cement holding together their social order. Finally, the males use sex to try to get food from the females.

SPIEGEL: Why so much sex? How did this behavior develop?

De Waal: It prevents infanticide, or the killing of young animals by the adult males, the leading cause of death in young primates. Because bonobo males have sex with all bonobo females, they have no idea which children could be theirs. We call this paternity concealment. Female chimpanzees use a different strategy. They leave the group shortly before giving birth and spend years avoiding the dangerous male groups.

SPIEGEL: What role did infanticide play in human evolution?

De Waal: A very important one. In humans, the family prevents infanticide. Next to language, the core family, consisting of a mother, a father and children, is the greatest difference between us and other primates.

SPIEGEL: How so?

De Waal: Humans became easy prey when they moved from the forest to the savanna, which deprived them of the option of climbing trees to flee predators. This shift made it necessary for the men to actively protect the women and their babies. Only as a result of this protection were women able to give birth in shorter intervals, perhaps once every two or three years. This meant that they could produce offspring about twice as frequently as apes. I would be willing to bet that this rapid reproduction is one of the reasons why we dominate the world today, and not the apes.

SPIEGEL: It was as easy as that?

De Waal: Of course not. The development of family entities has another, more important consequence. It enables men to cooperate far more effectively. Instead of constantly competing for the women with other men, each man essentially has a partner assigned to him, one with whom he can establish a family.

SPIEGEL: He forces her to stay at home, while he goes out into the world with his buddies to build bridges and land on the moon?

De Waal: Something like that. But there is still one problem. In this type of system, it becomes extremely important for a man that his wife not have sex with anyone else, which would mean that he ends up having to raise someone else's offspring. This is why men almost obsessively control their women. Extreme examples are the chastity belts of the Middle Ages or the burkas women wear in Islamic countries like Afghanistan.

SPIEGEL: Family and language are traits that you recognize as being unique to human beings. There is also another major difference: We have religion and ethics. Apes can't compete in that respect, can they?

De Waal: I'll admit that. But I do believe that religion and ethics are based on psychological building blocks that we share with related species. We have added a system of social pressure, with which we justify and emphasize rules. One of those rules is "Thou shalt not kill." It may be expressed by religious leaders or philosophers, but it merely signifies something that is deeply engrained in our consciousness.

SPIEGEL: When the Pope appeals to us to love our brothers, is he appealing to the apes in all of us?

De Waal: Essentially. I'm not saying that chimpanzees and bonobos are moral beings.

SPIEGEL: They're unlikely to be familiar with the categorical imperative.

De Waal: But they are. They're very familiar with the motto "Do unto others as you would have them do unto you." It's precisely the principle of reciprocity that I see, in addition to empathy, as the fundamental element in the psychology of all primates. We did an experiment in which we gave chimpanzees watermelons and then documented how they divided up the fruit among themselves. In the hours leading up to the experiment, we recorded which animals groomed which other animals' fur. The results were clear. The ape that divided up the watermelon gave significantly more to those apes that had groomed him earlier on.

SPIEGEL: You also mentioned empathy...

De Waal: Oh yes. For example, chimpanzees are quite good at comforting one another. If a friend is suffering, they hug him and attend to him. It's only our arrogance that makes us doubt that this is even possible. When someone brutally kills someone else, we call him "animalistic." But we consider ourselves "human" when we give to the poor.

SPIEGEL: On the other hand, the philosopher Thomas Hobbes said: "Homo homini lupus," or "man is a wolf to man."

De Waal: The evolutionary struggle for survival is really a self-serving series of blows and stabs, and yet it can lead to extremely social animals like dolphins, wolves or, for that matter, primates. I call the notion that we are nothing but killer apes the Beethoven fallacy. Beethoven was disorganized and messy, and yet his music is the epitome of order.

SPIEGEL: Is it possible that even the dream of a selfless society is the result of each individual's self-serving endeavors?

De Waal: No. Socialism cannot function, because its economic reward structure is contrary to human nature. Despite massive indoctrination, people are not willing to give up their own needs and those of their immediate families for the general good. And for good reason. Morality, after all, has nothing to do with selflessness. On the contrary, self-interest is precisely the basis of the categorical imperative.

SPIEGEL: Wouldn't that mean that capitalism is the more suitable model for human coexistence?

De Waal: A system based purely on competition also comes with significant problems. You can see this here in the United States, where there are too few constraints on market forces. It's a balancing act. Competitiveness is just as much a part of our nature as empathy. The ideal, in my view, is a democratic system with a social market economy, because it takes both tendencies into account.

SPIEGEL: Nevertheless, democracies have been the exception in human history.

De Waal: I don't think that's true. Hunter-gatherer cultures, in which we presumably lived throughout most of our history, are normally organized in a rather egalitarian fashion.

SPIEGEL: But the age of such small groups ended long ago...

De Waal: ...and the world is becoming smaller. This is precisely our greatest challenge. We, who think like animals living in small groups, must structure a global world. We believe in universal human rights and believe racism and war are wrong. On the other hand, it is our nature to be cooperative and loving almost exclusively with the members of the group to which we feel we belong.

SPIEGEL: In this respect, the violent chimpanzees aren't exactly a good model. Would we, in our efforts to bring our ideals in line with our nature, be better served to emulate the bonobos?

De Waal: Imagine if we didn't even know that chimpanzees existed. We would be forced to conclude that our closest relative is a friendly, sex-obsessed hippie, and we would probably come up with all kinds of theories as to where our aggressiveness comes from. It looks as though we have lots in common with both. On the one hand, we're good at making peace and perhaps even more empathetic than bonobos. We certainly have more sex than chimpanzees. On the other hand, we are territorial, power-hungry and even more brutal than chimpanzees.

SPIEGEL: Is there anything that's exclusively human, or do you see parallels to all our traits in the behavior of our furry cousins?

De Waal: People can fall in love, for example. And apes have no sense of privacy, which is closely linked to the concept of the family.

SPIEGEL: And what about consciousness?

De Waal: Do we even know whether chimpanzees or bonobos have a consciousness? Anyone who claims that we are the only primates with this trait should first tell me how we can even recognize consciousness from an external point of view. The only thing I'm sure of is that we are by far the most contradictory of all primates. An animal with this much internal conflict has never lived on this earth. In this respect, we don't have just one ape within us, but at least two. We have to live with this contradiction.

SPIEGEL: Mr. de Wall, thank you for this interview.

(Interview was conducted by editors Philip Bethge and Rafaela von Bredow.)