This is a collection of papers on a theme well described by its title. Seven of the ten contributors are primatologists, one an archaeologist, one an anthropological linguist, and one is a human developmental psychologist. Of the ten, eight were well-known names to me in language evolution, so this is a collection with a high concentration of scholars of distinction. A collection on human language origins by only primatologists would risk extreme imbalance, and one feels that the non-primatologists were included in the seminar from which this collection emerges to keep the primatologists focussed on the relationship between primate behaviour and human behaviour.
The issue of whether there is continuity between animal communication and human language is the focus of an ideological rift between linguists (with a few exceptions) and primatologists (with hardly any exceptions). Unfortunately, the factual issue of whether a discontinuity exists is often confused with the methodological issue of whether interesting explanatory accounts can be given of the discontinuity. Caricaturing somewhat, there seem to be two prevalent attitudes: (1) there is really no significant discontinuity between animal communication and human language, and therefore we have no need to invoke any mode of explanation specially designed to cope with discontinuities (e.g. phase-change-type explanations, emergence mechanisms, or macromutations); and (2) there is a significant discontinuity, which is, furthermore, beyond the reach of explanation, so attempts to ``bridge the gap'' are futile, often tarred with the label of Just-So Stories.
The contributions to this collection, while not exactly fitting the caricature under (1) above, tend (often with diplomatic cover-your-back caveats) to adopt the position that the early evolution of human language can be seen as a continuous (though unique) process originating directly in animal communicative capacities. None of the contributors effectively grapples with the major problem, that of the phylogenetic syntax explosion, as a result of which moderns humans command grammars whose complexities take thousands of academic pages to describe.
As the title suggests, the collection overall takes the position that nonhuman primates can tell us something about language origins. This runs counter to a view held by a fair number of linguists, that nonhuman primates can tell us nothing about language origins. Barbara King sets the scene of the whole contentious field very well in an introductory chapter, sketching the opposing extreme views held, how these views relate to their holders' academic agendas, and exposing inconsistencies in works of several of the best known writers in the field, such as Bickerton and Pinker. She treads a carefully reasoned tightrope between the view that there is no significant difference in kind between humans and apes, and the view that there was a quantum leap or major phase change from ape communicative behaviour to human language.
Some of the contributions are specialized and narrow, though good, while others are more wide-ranging in scope. Maestripieri reports a comparative study of three species of the macaque genus, concluding that the species whose social arrangements are most egalitarian-individualistic and least despotic-nepotistic have the greatest variety of distinct meaningful gestures. This is interesting and comforting food for thought for liberal humans, but we must remember that macaque communication is lightyears away from human language in complexity. Nevertheless, the point is taken that egalitarian-individualistic social arrangements in pre-hominids could have formed part of the preadaptive platform on which human language was built. Snowdon, also a primatologist, points to a wide range of basic similarities between primate signalling and human language, concluding ``it is very difficult to find explicit criteria that differentiate human language from the vocal communicative capacities of other species, yet it is clear that something is different about language'' (pp.112-113). Linguists might exasperatedly respond that they have been working for decades, even centuries, on what is different about language, and the right place to look for it is in the grammars of languages. Snowdon gets his linguistic terminology wrong in a few places, and his summary of linguistic universals is one-sided. While linguists should definitely be more aware of the primatological literature that Snowdon summarizes, the route needs to be travelled in the other direction as well, with anyone pronouncing on the evolution of human language consulting a range of linguists to get a sense of the full picture from the linguistic side.
Savage-Rumbaugh's article is the longest (too long). She argues for a view of science that would not rule out a priori the conclusion that apes think, have intentions, and can communicate in complex ways. Certainly there is a gulf between the kind of participant observation methods that Savage-Rumbaugh uses and traditional empirical psychological methods, with their emphasis on rigorously controlled experiment. Ironically, generative linguistic methodology, founded on a view of native speaker intuitions as data, is closer to Savage-Rumbaugh's own position than to the traditional psychological methods.
Gibson and Jessee review the comparative anatomy, brain structure and behaviour of humans and great apes in order to suggest that quantitative changes in the brain during evolution enabled humans to construct more hierarchically complex schemata, both in language and in other behavioural arenas, than other animals. They suggest that Homo erectus used language to coordinate action and that Neanderthals and modern humans were cognitively indistinguishable. But then, what might explain the extinction of Neanderthals in Europe coincident with modern human arrival? Davidson begs to differ. He is the odd man out in this collection, tending to emphasize ape-human discontinuity and very recent origins of distinctively human language, as late as 60,000 years, which seems to me quite implausible. This may be an example of how the agenda of one discipline influences what one is inclined to believe. Archaeologists, especially those impressed by the earliest art-forms, are perhaps bound to attach greater significance to eras where their data are richer.
McCune's paper adopts a more general and more plausible twist to the ``ontogeny recapitulates phylogeny'' theme. Instead of surmising about the phylogeny of one species on the basis of what is known about the ontogeny of modern individuals of that species, she compares the ontogenetic development of communicative behaviour across humans and nonhuman primates, finding some common threads, and speculating, reasonably, I think, that at least these common threads in ontogeny can plausibly be taken as indicative of the early stages of the phylogeny of meaningful communication in humans. The paper emphasizes the very early stages in communicative behaviour, from meaningless grunts, gradually through more meaningful grunts, to the first meaningful signs. The theme of a staged development to meaningful signs is also empohasized by Burling, via a stage he calls ``motivated signs'', which resemble C.S.Pierce's icons. Both Burling and Wilcox, in somewhat similar ways, argue for particular continuous routes from animal communication to something like human language, Wilcox emphasizing gesture and ritualization, and Burling emphasizing iconicity of signals and conventionalization.
Before I read this collection, I was not dismissive, as some linguists are, of the relevance of ape studies to language origins, but some of the articles in this book have made me take evidence from nonhuman primates more seriously than before. I would not recommend all the papers in this collection to students of the origins and evolution of human language, but in my personal view King's introduction, and Gibson and Jessee's paper stand out as highly recommendable, followed closely by McCune's and Burling's.