Grooming, Gossip, and the Evolution of Language: ,

There is no denying that Dunbar (The Trouble with Science) makes something of a splash in the field of evolutionary psychology when he argues that the main impetus behind the evolution of language is the human need to gossip. Of course, readers should not be fooled by the seemingly flip use of the term ""gossip,"" since Dunbar's gossip refers to any type of social conversation. For Dunbar gossip constitutes the linguistic equivalent of grooming, the means by which primates, especially chimpanzees and baboons, establish relations within a group. Dunbar checks into research in the fields of cognitive psychology, primatology, endocrinology, linguistics, and neurology to argue that the growth in the size of nomadic human groups (from the 40-60 for apes to about 150 for our human ancestors) and our neocortex best explains the development of language. In Dunbar's formulation language performed the important function of holding these large groups together by substituting the energy-efficient ""vocal grooming"" for the more time-taxing physical act. With vocal grooming, early humanity could now move in larger groups, which afforded them protection from predators, and still have time to gather food over large areas. Concisely and clearly written for lay readers, Dunbar exhibits a gift for argument and explanation most science writers would give their right hand for. And while the penultimate chapter overreaches in its sociobiological claims, explaining in evolutionary terms phenomena that seem more cultural and economic in origin, one still admires Dunbar's ability to synthesize research in so many fields without taxing our interest. (Mar.)