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Harvard University biological anthropologist (retired) and co-founder of the Kibale (Uganda) Chimpanzee Project in 1987 with Elizabeth Ross. He is the author of “The Goodness Paradox: How Evolution Made Us Both More and Less Violent”, and “Catching Fire: How Cooking Made Us Human

How did you become interested in the science of nature?

I was a naturalist as a kid, following my parents' interests. Bird-watching and adventure took me to the wild, but it was when I encountered essays on evolutionary theory in SA Barnett's 'A Century of Darwin', in my early teens, that the wild became truly intriguing. I found a way to Zambia and spent 9 months in a savanna park before going to university. That was 1967, and I've done fieldwork in Africa every year since then (except one -the year my eldest son was born).

How did the study of chimps and human evolution come about?

I was always interested in human behavioural evolution but it was chance that got me studying chimpanzees - a recommendation from my tutor Harold Pusey at Oxford, based on his daughter Anne's experience. I expected to study them for a short time, and then move on to other animals. And I did - after a Ph.D. based on work at Jane Goodall's site, I studied vervet monkeys, then people in the Congo. But once you're confronted with chimpanzees, it's hard to ignore the questions that they force on us about our place in nature. These seemed much more than causal intellectual interest, though amazingly that's often how they're treated. They make us think in a

realistic way about what it means to be a species that's evolved, and what it means to be an individual made of the same essential matter as another great ape.

What particular aspect of chimp behavior fascinated you the most?

A big question was about the role of violence. There was unambiguous evidence from Gombe that chimps sometimes kill each other, but many people didn't take it seriously, blinded by hope (as I interpret their reaction) that natural selection couldn't have favored intense aggression

in one of our closest relatives. It was obvious to me that the nay-sayers were wrong, because the patterns of chimpanzee violence fit so clearly into their ordinary lives. The way to test that idea was to see how often violence would turn up in other populations. So I looked for somewhere where I could study chimpanzees (and take my family while doing so) and began in Kibale in western Uganda in 1987.

Since then, we've had chimpanzees killing other adults in two separate areas in Kibale, as well as in Budongo, another Uganda site. So as time goes on the role of killing among chimpanzees is becoming clearer. Of course that doesn't mean that natural selection has necessarily been relevant to the evolution of human aggression, but it does give us the opportunity to understand how it works in another species, and in practice, the evidence for parallel patterns of aggressive evolution in chimpanzees and humans looks stronger all the time. There's still this old social-science view around that says our own dear blank-slate species couldn't possibly have a history of natural selection for anything as nasty as aggression. It seems to me a dangerous idea because it leads people to be naive about the real-life dangers- for instance, the way that under the"right" circumstances, men are so prone to the excitement of opportunities to use violence for personal satisfaction.

We're still at a very early stage of understanding the human genetic and endocrinological predisposition to violence. The apes offer richer hypotheses than most other species, because we have so much in common with them. Simply to declare, as the late great Stephen Jay Gould did for example, that the similarities between chimpanzee violence and human violence are too superficial to be in the least informative, is a travesty. We have to be careful to use animal behavior well, but we ignore it at our peril. The good thing, I believe, is that much of the problem stems from mistrust about the information, so ultimately, the best thing we can do is simply show the facts. As the data from the wild build up, I'm convinced the academy will become more realistic. The big question is whether the interest in great apes will swell to the point where the world can commit to protecting them in the wild in time to do so.

How important was Jane Goodall and the work you did at Gombe in your career as a


Jane Goodall gave me the opportunity to study primates in the first place. Even though she was working mostly in Serengeti more than in Gombe during my three years there, she was a huge

influence. She taught me the critical importance of thinking all the time one is observing: why did

the individual do that?

What other chimp behavioral traits have you documented since you and colleagues

observed Imoso, a male chimp at Kibale, using a tool as a weapon by beating up Outamba, a female chimp, a trait previously

thought to be exclusively human?

In December 2010 Sonya Kahlenberg and I published data showing that juvenile females and

males tend to use sticks in different ways. If someone is carrying a stick to no apparent purpose, they are more like to be a female. Because they occasionally treat sticks as if they are caring for them, such as patting them or making a nest for them, this behavior looks like a form of doll-play. On the other hand males are more likely to use sticks as weapons when they are older, and the few observations that we have of juveniles using sticks as weapons by throwing them or hitting

with them suggest that male juveniles do it more often than females.

Are we able to distinguish between chimp behavior learned from humans and chimp behavior independently developed?

I am not aware of any convincing examples of wild chimpanzee behavior that have been learned from humans, but there are some suggestions. Most or all chimpanzee populations west of the Ivory Coast sometimes smash nuts with natural hammers of wood or stone. Conceivably a group

of chimpanzees learned to do this after seeing humans doing something similar, or more likely after finding a place where humans had left hammers and some broken nuts with edible bits easily noticeable. But a hammering action is common among chimpanzees, such as when they hold a hard-shelled fruit and hit it against an anvil to open it. It seems much more likely that chimpanzees have invented their various tool-using techniques independently of humans, partly because it is hard to imagine them watching humans (rather than running away) and partly because most tool-using is very different from anything that humans can be seen doing. In Kibale, for example, the commonest form of tool-use is wiping the penis with leaves after copulation!

Have researchers reached a point where it's possible to speak of chimp cultures in the same way we talk about human cultures?

We can certainly talk confidently about chimpanzees showing social learning, and about learned traditions in the wild that vary among populations. So 'chimpanzee culture' is a

common-place concept nowadays. However chimpanzee cultures are very different from human cultures because chimpanzees have no social norms that we know of.

Are you still involved with the Great Ape World Heritage species project and if so what progress have been made over the past couple years in making the great apes the

world's first World Heritage species?

The Great Ape World Heritage Species Project ran for several years with the aim of bring the plight of the great apes to the world's attention, and in the hope of making them into a

new category of protected species, 'World Heritage Species'. Eventually we were persuaded that the political challenges of creating that new category may be overwhelming. GAWHSP works closely with UNEP's Great Ape Survival Project (GRASP), and helped set up GRASP's Scientific

Commission, which now monitors the status of great apes worldwide. GAWHSP's role has shifted mostly into practical aims of helping to increase the conservation status of specific populations.

How did the chimp research in Kibale figure

into your theory that cooking kick-started the

evolution of modern humans?

I have always been interested in the food choices and feeding behavior of chimpanzees, and try to

sample all their foods for myself. Many of their foods are sufficiently palatable to be edible, but there are very few one can fill one's stomach with. And even if you can, you will be hungry very soon. Eventually I realized that the gap between what they eat and what we eat actually means something.

What are some of the conservation challenges

facing chimpanzee populations at Kibale,

Bugondo forest and other chimp areas in other parts of Africa?

In Uganda there is little hunting of chimpanzees except for their being caught incidentally in snares

set for game animals. So the big threat is loss of forest to the growing human population. Uganda has one of the world's fastest population growth rates, so it is easy to imagine the future possibility of political pressures to de-gazette protected land.

And how are those challenges being met by

you and other primatologists?

In Kibale, as in Budongo, Kalinzu and several other forests, there are eco-tourism facilities that benefit the central government as well as local people. When President Yoweri Museveni opened the International Primatological Congress in Entebbe in 2006, he praised the contribution that primate ecotourism is making to national development. Like other primatologists, I have been involved in initiating and supporting these projects. But they are worth little without conservation education. I work with Elizabeth Ross on the Kasiisi Schools Project that has invested in raising the quality of education in general for schools around Kibale, including a focus on conservation education. A recent study found that around Kibale, most households felt that they benefit

from the Park, and although environmental services were appreciated in general, the single benefit

most cited by local committee chairmen was the improvement in school classrooms and staff houses. Continuing investment in education by researchers working in the forest seems a promising way to help people realize the benefits of maintaining forests for future generations.

Originally published in 2012 in SWARA Magazine.


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