It's sometimes unclear in this curiously engaging study whether chimpanzees and their cousins are where we humans came from or where we ought to be heading. Certainly they seem to have developed systematic ways of preventing violence—and limiting it when it occurs—that are the equal and might be the envy of our more combative species.
The Netherlands-born De Waal, now a research primatologist at the Wisconsin Regional Primate Research Center in Madison, doesn't romanticize the animals he studies. One of the most striking incidents he describes is a murderous attack by two male chimps upon another at the Arnhem Zoo in the Netherlands in 1980. But he describes the assault to show how exceptional it was for the chimps to break their group's rules, in which most aggression took the form of threats. Such displays were usually met with conciliation in the form of averted eyes or bowing; actual attacks were often followed by reconciliatory acts such as mutual grooming.
Everyone seems to be constantly testing each other—confirming his or her place in the social order—but these creatures also seem generally willing to accept that place. Nonhuman primates, De Waal concludes, "sustain their communities by a highly developed cooling system that prevents overheating, explosion or disintegration of the social machinery."
De Waal convincingly argues that the animals he writes about—chimps, their (and our) cousins the bonobos, stump-tailed macaques and rhesus monkeys-are sufficiently interesting in their own right. But he can't resist comparing their behavior with that of humans. He notes, for instance, that "the erroneous image of women as noncompetitive may result from a tendency similar to that of female chimpanzees, that is, a proclivity to stay away from rivals." He also relates ape and monkey aggressive behavior to the human theory that arguments are healthy: "Screaming and shouting followed by tenderness may actually strengthen a bond, in that the sequence assures both parties of the viability of the relationship."
Because the animals he has studied have been captive and little field research covers intergroup behavior, De Waal is limited to internal disputes comparable to fights among residents of a country. But he does extrapolate his findings enough to question disarmament as a way of solving larger human conflicts: "If my studies of monkeys and apes contain any lesson for the global arena, it is that parties who need each other for one reason or another are less likely to fight, and if they do fight, they are more likely to make up afterward. If, on the other hand, a sound basis for the relationship is lacking, I am convinced that the two sides will fight regardless of the size and condition of their teeth." (Harvard, $29.95)