PALEONEUROLOGICAL EVIDENCE FOR LANGUAGE ORIGINS

If there is any hallmark that might be said to be unique to the human animal, it is surely the ability to speculate about the origin of language. I have too much respect and regard for the intellective capacities of chimpanzees to imagine them prone to such exercises in egoistic futility. Thus I approach the topic with a mild case of schizophrenic serenity, in which I simultaneously share a n agreement with the very rational Frenchmen of the Nineteenth Century who banned such discussions from their learned society, and yet share a delight that the topic is available for organized discussion from so many viewpoints, disciplines, and scientific experimentation as represented by the interactants of these conferences. For me, a t least, the very fact that this Conference has been organized, and that human animals are ready to engage in a great “garrulity” over the merits and demerits of essentially unprovable hypotheses, is an exciting testimony to the gap between human and other animals, whether continuous or not in nature. My assigned task is to assess the paleoneurological evidence for language resulting from our rather meager fossil hominid record. This is, at least on one level, an exceedingly simple task, since there is no good paleoneurological evidence as yet from the fossil hominid record that either proves or disproves when this or that hominid acquired the capacity for language. At the level of precise unambiguity, the endocasts leave much to be desired, as I have repeatedly emphasized. 1-8 Still, these are the most proximal evidencial links we have, and when combined with the other indirect lines of evidence from the fossil record, such as stone tools made to standardized patterns of arbitrary shape, or the rest of the musculoskeletal evidence, or the remaining archaeological record of different functioning sites, the combination raises significantly, I believe, the probability that this uniquely human activity came relatively early in hominid evolution, perhaps two to three million years ago.7-9 I have tried in most of my publications to suggest that “reorganization of the brain,” i.e., the study of the quantitative changes in the various neural systems of the brain and their integrated interactions, coupled with our ever-increasing knowledge of neurofunctioning, is a profitable way of approaching the problem of human (indeed any taxa) brain evolution. Most of those earlier publications were a reaction to the views most popular during the 40s to the early 60s, in which brain mass, taken alone, by and of itself, was regarded as the level a t which human behavioral specificities would be eventually understood. Consequently, I purposely played down the role of brain size alone in the case of human evolution. Perhaps I went too far, judging by the reactions of some of my critics.“J-13 Still, I never claimed that brain size was totally meaningless; only that it was insufficient as a lone datum level from which human behavioral evolution, or even a truly comparative neurobiology, could be understood.~4-~6 In the last few years this position is being met with serious rebuke by other scientists,lO-IJ who have raised a number of issues with greater clarity than existed before. In this paper, I will address myself to certain of these criticisms as they