Wild about chimpanzees

Chimpanzees and their sister species, bonobos, certainly engender a passion in those who study them. Studies of chimps in the wild have 35 years of solid history behind them and the chimpanzee is a high-profile primate that captures the public imagination. Chimpanzees are sexy science.

But what of chimpanzee cultures? Biological anthropology and cultural anthropology have tended to eschew one another, split as they are along the lines of nature versus culture. Recently, however, there have been suggestions that rapprochement between cultural and Darwinian camps might be in the offing.

In consequence, Chimpanzee Cultures is a title to catch the eye. The dust-jacket on this book proudly informs us that "the world's leading authorities . . . offer the most thorough documentation to date of the remarkable variety of behaviours in these species (chimpanzees and bonobos) so tantalisingly close to our own". Certainly, the authorship of the papers covers most of the leading figures in chimpanzee research and the book has a distinct milestone feel.

The aims are made explicit at the outset: to create a discipline of "cultural primatology" by using the tools of the cultural sciences and encouraging the use of ethnography in comparing chimpanzee populations. This endeavour not only requires that there be sufficient variability across populations for ethnography to be appropriate but also that the concept of culture can be usefully applied in explaining this variability. In fact, the material on chimpanzees far outweighs the material on culture.

The quality of material on the subject animals is high. All the papers are original, many containing previously unpublished data, and they do an excellent job of highlighting behavioural diversity.

Tool use obviously receives attention: it is a remarkable and highly relevant fact that every chimpanzee population ever studied uses tools differently. The sophistication of chimpanzees extends beyond cracking nuts with stones however. An excellent chapter on hunting strategies shows how a tradition of collaborative hunting has evolved (culturally not genetically) at one field site and not at another.

The chapter on medicinal plant use is striking. For ourselves, medicine exemplifies the transmission and elaboration of knowledge down through generations. But sick chimpanzees seek bitter-tasting plants that we know to contain antibiotics; plants which do not comprise a part of their daily diet. It is implausible to suppose that individuals discover these plants by a random sampling of vegetation and thus we must suspect the existence of a behavioural tradition transmitted by observational learning.

The final section is devoted to the cognitive abilities of chimpanzees, clearly a limiting factor on their cultural sophistication. Kanzi, the bonobo prodigy who quietly learnt language while trainers were unsuccessfully trying to teach his mother, makes a fitting appearance here. The fact that, unaided, he absorbed an ability that was highly species-atypical testifies to great adaptive flexibility in this species.

A linguistically competent ape is particularly significant since social anthropologists have tended to see culture as necessarily unique to humans by virtue of being mediated by symbols and language.

Chimpanzees whose habitual companions are humans are said to be enculturated. The more we learn about chimpanzee personality, particularly (and rather ironically) in captivity, the more we are inclined to see them as persons.

Personhood in ourselves is certainly a consequence of having a large brain and a rich and complex representation of ourselves and our relation to the world. However, these are just the tools of the job, as it were: what imbues us with personhood is the culture we absorb. Kanzi, his trainers claim, has acquired something of the personality of a human child. Should we regard all chimpanzees as persons, enculturated by the group they are raised in? That is a possibility that this book raises.

Although Chimpanzee Cultures comprehensively reviews the diversity of chimpanzee behaviour, a shortcoming of the book is the absence of much synthesis of this diversity into hypotheses concerning whether chimpanzees really are cultural in the sense applied to humans. The editors seem to be promoting a paradigm shift in the way we think about chimpanzees but they have not really pulled it off.

Some of the papers consider how behaviour might be culturally transmitted but many do not. I was surprised to find no definition of culture or discussion of what previous scholars had to say on the subject: perhaps the editors should have invited a cultural anthropologist to make some observations on the assembled papers.

A notable exception to this is Michael Tomasello's chapter on "The question of chimpanzee culture". Tomasello explicitly considers what ought to be the central question: whether diversity across populations is sufficient to constitute culture, or whether it is the mechanism by which this diversity arises that should be at stake. In fact, Tomasello argues convincingly for important differences in social learning by humans and apes based on the former's purportedly unique ability to understand another's intentions.

Who should read this book? Those seriously studying chimpanzees will have already ordered their copy. Psychologists, social scientists, linguists and ecologists should certainly consult the book before making statements about what chimpanzees do or do not do: this will remain the definitive sourcebook for some time to come. Also, all but the most entrenched social and cultural anthropologists should benefit from attending to this first attempt at the reifying of cultural primatology.

This is a book chiefly aimed at the scholarly community, yet it carries an important message for all of us. Wild chimpanzee populations continue to decline through habitat destruction and hunting for bushmeat: the bare bones of this are made clear in the book's final chapter by Jane Goodall. The dwindling of any species through human short-sightedness is depressing, but chimpanzees present a special case. Chimpanzee Cultures provides ample evidence that chimpanzees are not simply carbon copies of one another. The species may survive but the extinction of cultures may be proceeding as we speak.

Thomas Sambrook is a member of the Scottish Primate Research Group, universities of St Andrews and Stirling.