Sometime in the Miocene, apes started going extinct. For reasons still unclear the more specialised Old World monkeys got the upper hand, proliferating into the current 100 or so species of monkey found today. Extrapolating from the extinctions seen in the fossil record the apes should have shuffled into palaeontological history about three million years ago.
Yet five genera remain. Apes are relatively primitive primates, much closer in many respects than the Old World monkeys to their shared common ancestor. Specialist ape adaptations are limited to swinging below branches rather than running on top of them, not having a tail and having an unusually large brain. The other important thing about apes is, of course, that we are one of them.
Great Ape Societies, born of a meeting of luminaries in Baja two years ago, is the descendent of The Great Apes, published 17 years ago; a similar book derived from a similar meeting - in some cases of the same luminaries. While the editors are keen to highlight the continuity established, the 1979 volume now seems incredibly dated; it predated the meteoric rise of socio-biology as guiding dogma in the functional explanation of behaviour and the great developments made in comparative cognition. This omission is set to rights in its successor.
Great Ape Societies is predictably good, given the concentration of expertise found within. The title is something of a misnomer; social phenomena tend to drift into ecology at one end and cognition at the other. Nor are the species of great apes fairly represented; the majority of the papers concern the common chimpanzee and only one is devoted to the orang-utan - admittedly not the most sociable of species. In fact, this volume is more realistically a sequel to the recent Chimpanzee Cultures with which it shares the majority of its contributors.
The book is divided into six sections: an overview, social ecology, social relations, minds, apes compared and the modelling of ourselves. I am consistently impressed by the motley assortment of theories that ape scholars kick up and am unable to decide whether this is because the subjects are so complex, and therefore foster creative thinking in the field, or whether its practitioners just tend to be wacky. At any rate, the field is not stagnating; Barbara Fruth's contribution on nest building seeks to derail the steady progress of the ape tool-use debate and focus attention on the material skills for, and the psychological consequences of, a good night's kip. Maybe "man the hunter" scenarios have unfairly promoted the importance of tool use, and this is an interesting idea, but it is in danger of being seen as a bit twee until more evidence is produced. In another of the more conjectural chapters, Sue Savage-Rumbaugh tries to convince us that pygmy chimpanzees leave trampled vegetation as markers for their conspecifics to follow. This follows from reports that chimpanzees drum specific patterns for the same reason.
Socioecology, the study of social and ecological correlates and the less vilified sister of sociobiology, is a guiding framework for many of the mainstream field data chapters. There is something intellectually stimulating about a subject that in the space of a few paragraphs can wander from fruit trees to sperm via gut length and infanticide. In particular, the pygmy chimpanzee's virtual absence from the 1979 volume is rectified here, with several specific comparisons with the common chimpanzee. The low levels of aggression both between individuals and groups, the virtual equality of sexes and the variety and insatiability of sexual activity do little to disabuse us of the popular stereotype of one big Zairean love-in. On the social side of things, Frans de Waal continues his quest to single-handedly anthropomorphise primatology but provides a nice reanalysis of the function of aggression along the way.
The use of living apes as reference points for a reconstruction of human origins is an idea that has gone in and out of fashion. Its relevance, however, has massively increased since the time of the original "Great Apes" conference due to the development of molecular clocks that allow us to establish who is related to whom and when the species split. It is now widely accepted that chimpanzees are more closely related to humans than either is to any other ape and that the human-chimpanzee split occurred about six million years ago. However, one of the problems of using an ape as a human-ancestor model is which species to choose since they are so different, particularly in their social systems. In fact, baboons have often been used as a model because unlike the apes, they are savannah adapted like our hominid ancestors. For this reason it is nice to see Jim Moore's thoughtful chapter on savannah chimps as a way out of this dilemma. He also provides en route an ironic but salutary "thesaurus" of 12 synonyms for what is essentially conjecture (model, scenario, analogy, etc) used by human evolutionists to confer status on work that is short on evidence.
Great Ape Societies presents no radical new synthesis of material; if anything it stresses the diversity of a discipline determined by its subject matter rather than its methods. It is an excellent statement of the state of research, suitable for advanced undergraduates or above.
The book ends as it begins, on the pressing issue of the conservation of great apes. It is ironic that a small fraternity of ape species should survive the Miocene extinction only now to be threatened with destruction by one of their own number.
Thomas Sambrook is a research associate, department of anthropology, University of Durham.
Great Ape Societies
Editor - William C. McGrew, Linda F. Marchant and Toshisada Nishida
ISBN - 0 521 55494 2 and 55536 1
Publisher - Cambridge University Press
Price - £55.00 and £19.95
Pages - 328