IT'S A LAZY AFTERNOON IN LAWRENCEVILLE, Ga., and everything should be going Jimoh's way. As the top-ranking male in a group of 20 chimpanzees maintained by the Yerkes Primate Research Center, this muscular, black-haired 29-year-old is every female's favorite escort. And today Peony, one of his own favorites, has a red swelling on her rump, signaling a period of sexual readiness. As the rest of the group lounges, Jimoh sidles up to her, sporting an erection, and the two are briefly united. But when a pair of youngsters sense they're missing out on some fun, they bound over to throw dirt and pound on the amorous couple. Jimoh could throttle the punks, but the alpha male withdraws with a look of calm resignation and waits for a more auspicious moment to mate. "He has to be very tolerant of the juveniles," explains primatologist Frans de Waal. "He can't afford to alienate their moms."
Can't afford to alienate their moms? Until recently, no serious scientist would have uttered such a thought. As everyone knew, humans were cultural animals, born and raised to restrain themselves. Other primates were just plain animals. But the conventional view -- both of them and of us -- is shifting. A growing number of researchers are studying human and animal social conventions just as they would diets or mating patterns -- not as fixed ideals but as biological adaptations. And their findings suggest that the roots of morality are far older than we are. As de Waal shows in his new book, "Good Natured" (296 pages. Harvard University Press. $24.95), we're much like other primates when it comes to sharing resources, settling differences and enforcing order. Unfortunately, as other scholars are discovering, the ethical impulses we share with our furry cousins can undermine our best efforts to create a stable community.
De Waal has spent two decades top-pling misconceptions about chimpanzee society. He has shown, for example, that males achieve dominance not through sheer force but through shrewd politics. In his new book, he builds on that insight, arguing that the hierarchy is a "mutual contract" between leaders and subordinates. De Waal recounts how Jimoh once caught Socko, an adolescent male, mating with a female he had been pursuing himself. "He chased him all around the enclosure -- Socko screaming and defecating in fear." But when the females in the group joined in an angry howl of protest, Jimoh called off the attack and walked away with a nervous grin. "One never hears [such a protest] when a mother punishes her own offspring, or when an adult male controls a tiff among juveniles," de Waal writes. "Thinking in terms of rules and violations may help us [understand it]."
It may also help us understand the chimps' food-sharing rituals. Visit the lush, 117-acre Yerkes field station on an August afternoon and you'll find de Waal's research assistant Mike Seres clipping fresh shoots of bush clover, honeysuckle, sweet gum and muscadine. When he tosses the bundles into the chimps' compound, the rules of rank are briefly suspended. Within minutes, the chimps who haven't secured their own branches gather around someone who has. Despite an occasional skirmish, everyone ends up with something to chew on. De Waal has found that physical attacks increase ninefold when branches are tossed into a pen -- but not for the reason you'd expect. The chimps use violence not to secure food but, more often, to rebuff food seekers who have previously failed to share. The implicit moral rule: "Those who seek favors must grant them."
As moral actions go, punishing ill deeds is pretty rudimentary. But chimps sometimes rise above side-taking to exhibit what de Waal calls "community concern." A creature that can survive only in a group is right to perceive social disarray as a threat to its own well-being. And as de Waal recounts from experience, chimps are exceedingly sensitive to disharmony among their group mates. High-ranking males often act as beat cops, quelling disputes before they escalate into riots. Females practice a sort of diplomacy, drawing angry rivals together and encouraging them to reconcile. And when rivals embrace, signaling an end to their hostilities, the entire colony may erupt in joyous pandemonium.
Chimps may not think consciously about harmony; they pursue it as instinctively as they do sex. But de Waal sees in their communal spirit the seeds of civilization. "Human morality can be looked at as community concern made explicit," he writes. "Our ancestors began to understand how to preserve peace and order -- hence how to keep their group united against external threats. . . . They came to judge behavior that systematically undermined the social fabric as wrong, and behavior that made a community worthwhile to live in as right."
Alas, that's not to say that charity comes naturally to us and cruelty doesn't. Social impulses may flourish when they're useful to individuals, but you can count on them to wither when they're not. Mutualism is the rule among groups of Olympic marmots, furry rodents that eke out their living in the rocky meadows of the Olympic Mountains. The woodchuck, a related species found in lush lowland forests, is less dependent on its neighbors -- and it treats them accordingly. It's the same for chimps and humans. "Different environments require different degrees of moral solidarity," says John Tooby, an anthropologist at the University of California, Santa Barbara. "We tend to be convivial when it pays."
When it doesn't pay, ruthlessness is often the rule. The famed Jane Goodall observed male chimps in Africa patrolling the borders of their territories, mounting gang attacks on members of neighboring groups. "Males race forward and jointly attack mother-infant pair," reads one of her team's field notes. "Mother loses half an ear. . . . Infant alive and calling for four minutes while being eaten." To anyone who follows the news, that death-squad dynamic should sound chillingly familiar.
If we're quick to deny outsiders any moral consideration, we're even quicker to cheat on our comrades when we think we can get away with it. The chimps at Yerkes may understand rank and reciprocity, but they'll gladly slip out of sight to cop some illicit sex, or feign illness to avoid sharing a choice piece of food. If you think humans are different, consider that a 1994 poll found one American in four would steal $10 million if he knew he wouldn't get caught. Freeloading is hard to get away with in a small group; as de Waal has found in his food-provisioning experiments, cheaters are easily identified, and no one forgets who they are. Throughout vast stretches of evolutionary history, our own ancestors lived in groups of less than 100, where face-to-face accountability would have been the norm. But with the advent of agriculture 10,000 years ago, populations exploded. For the first time, groups of primates had to codify social norms and create governments and religions to administer them.
Not suprisingly, these brave new institutions have turned out to be as troublesome as they are necessary. As our collective efforts make life more comfortable, each of us ends up with more to lose, and the case for self-sacrifice starts to ring hollow. As Dartmouth political scientist Roger Masters observes in his new book, "Machiavelli, Leonardo, and the Science of Power" (384 pages. Notre Dame Press. $32.95), "the very success of [civic] institutions re-creates the pressures that made [them] necessary in the first place." It's comforting to know that notions of right and wrong are part of our animal heritage. But it's not at all clear that our innate moral sense is up to the challenges we've created.