In mid-September of this year, Harvard professor Richard Wrangham stood before an audience at the university and told of a "startling" new development in weapons technology. But the talk Wrangham gave that day did not concern dirty bombs or weapons-grade anthrax. There was no mention of Al Qaeda or Saddam Hussein. Instead, to the ominous opening chords of Richard Strauss’s Also sprach Zarathustra, Wrangham faced his rapt audience and produced ... a stick.

As instruments of destruction go, tree limbs aren’t generally held in such esteem. But this wasn’t just any old tree limb. This was the tree limb with which Imoso, a male chimpanzee in Uganda’s Kibale Forest, had beaten the tar out of a female chimp named Outamba. In the space of a few minutes, this thuggish, enterprising ape may have revolutionized chimpanzee society. He certainly succeeded in turning the field of primatology on its head.

"This is the first time any animal other than humans has been seen to pick up clubs as weapons and use them against others of their own species," explains Wrangham, a 54-year-old professor of biological anthropology and world-renowned authority on chimpanzees. "This is the first repeated hitting. This is picking up a stick and wham-wham-wham-wham!"

Even more remarkable than the initial whamming, Wrangham adds, is the fact that matters did not end there. In July 2000, a little over a year after Imoso’s initial attack, a younger chimp named Johnny was seen using a stick to beat another ape senseless. To date, five separate incidents of weapons use have been recorded by Wrangham and his fellow researchers. In this sense, Imoso’s makeshift club was the A-bomb of sticks, the space-based laser beam of sticks.

Despite being a groundbreaking, even historic, development, the discovery of weapon use among chimps garnered little in the way of press coverage — which is perhaps understandable. At the time of Wrangham’s Harvard talk, the country was consumed by the anniversary of the September 11 attacks — not to mention the looming prospect of war with Iraq. The fact that a few chimps had taken to beating each other over the head with branches paled beside the terrible violence that seemed about to engulf the world.

But then, when it comes to the study of warfare, primatology has never commanded much respect. After all, it would seem that chimps, even those who take up weapons against each other, have little bearing on the current world crisis — with its complex web of religious, territorial, and economic determinants. As if to drive this point home, a number of Harvard professors were recently invited to contribute to a paper on terrorism for the National Academy of Sciences. The School of Public Health was represented in the report, as were the John F. Kennedy School of Government and the chemistry and economics departments. No one, though, thought of asking Dr. Wrangham what his research might lend to the study.

But Wrangham insists he’s not losing any sleep over the snub. "I don’t want to foist myself upon the debate," he says. "I think it’s important that [primatologists] are not given a false air of authority to talk about the specific political issues. I recognize that what I do is not like physics, where you’re suddenly going to be able to develop something — here’s your new lump of energy or your new medical device. It’s extremely unlikely that you can use these studies in any immediate practical sense."

Yet Wrangham is brimming with theories about September 11 and its aftermath — many of them founded on what he has seen in the forests of Kibale. "It seems to me that the most important contribution I can make is to add to the sense of danger, the sense of realism," he says. "What the chimpanzee studies are telling us is how easily natural selection can favor these sorts of patterns of violence and how ridiculous it is to think that if we can just persuade humans to be nice to each other, then they will be. You have to take a very hard-headed approach to it."

Wrangham, who has been studying chimpanzees in the wild for over 30 years, certainly knows a thing or two about warfare — at least as it pertains to apes. In the early ’70s, he was among the first primatologists to note the tendency of chimpanzees to conduct so-called lethal raids against neighboring groups — a momentous discovery. In his 1996 book Demonic Males (Houghton Mifflin), a study of chimpanzee aggression, he describes one such attack:

The raiders rushed madly down the slope to their target. While Goliath screamed and the patrol hooted and displayed, he was held and beaten and kicked and lifted and dropped and bitten and jumped on.... His aggressors showed their excitement in a continuous barrage of hooting and drumming and charging and branch-waving and screaming.

While this scenario may sound nothing like modern human warfare, Wrangham insists that the motives for the assault were the same as those that drive conflicts among human societies: the acquisition of territory and resources, the enhancement of status, and the sheer will to conquer. "One of the amazing things is how there are these similarities between nation-states and chimpanzees in a group," he says. "We are the only two species of mammals who raid territories."

That humans and chimpanzees display similar patterns of behavior shouldn’t come as too much of a surprise. Recent studies have shown that the two species’ DNA make-up is about 99 percent identical. Indeed, there are many primatologists who believe that modern-day chimps are a fair representation of what our own ancestors must have looked like, and acted like, six million years ago; Wrangham has often described the animals as "time machines." "The underlying emotional systems that guide humans," he says, "are almost certainly very similar to those that guide chimpanzees."

The implications of this statement are troubling. If aggressive chimpanzee behavior corresponds to our own aggressive behavior six million years ago — and also to our behavior today — this implies that our violent tendencies have persisted throughout our evolutionary history. In other words, humans are hard-wired for violence. We’re stuck with it. "There is that implication, that’s right," Wrangham says. "We’re stuck with the propensity for violence, at least. That is the slightly alarming thing about this. It is daunting."

Even more daunting is the fact that chimpanzees are not only capable of the same kinds of group aggression that we are, they’re also capable of the same kind of wanton barbarity. In Wrangham’s office there is a picture of a corpse — a chimpanzee who has been set upon by aggressors. The animal is lying face down, frozen into a kind of crucifixion pose, as if he had died while being pinned down. Strips of skin have been peeled from his body. He bears the marks of countless puncture wounds and contusions. In another photograph, one of the victim’s blue-gray testicles lies nestled in the brush. The chimpanzee had been tortured to death.

Conventional wisdom holds that man’s propensity for sadistic violence is a sickness, a horrible psychic quirk. Wrangham’s theories, though, suggest that the inclination to commit extravagant atrocities is a part of our biological make-up — a mechanism of natural selection. In the light of Kibale’s marauding apes, the mob of teenage Milwaukee boys who recently chased down and viciously beat a man to death were not an aberration — they were simply engaging in the kind of territorial violence that young males have engaged in since the dawn of our species.

Understandably, such theories do not enjoy widespread popularity.

In 1987 — 15 years after Wrangham first reported on warfare among chimps — a group of scientists issued a document called the Seville Statement on Violence. In the paper, the scientists declared that war "is a product of culture," implying that, given a bit of cultural tweaking, warfare can be eradicated.

"This seems to me to be foolish optimism," Wrangham says. "Even in the scientific area, there’s a tendency to allow hope to overcome reason. So you have people writing that humans are basically good and cooperative, and where we have aggression and war it’s all an abnormal mistake that we can easily overcome. I see that they would get a readier reception than someone like me, and I understand that, because nobody wants bad news. But it’s putting our heads in the sand. Therefore, it’s dangerous."