Human Evolution at the Crossroads. "Essays of a Humanist" by Julian Huxley Chatto arid Windus, 288, 30s by Walter F. Bodmer- '-_.. The central theme in this collection of essays by Julian Huxley is the importance of what he calls "Psychosocial Evolution" in a reappraisal of Man's present and future position on earth. The topics covered range from the description of an expedition to a bird sanctuary in Spain, to an attempt to define a new religion based on evolutionary humanism. As has often been emphasized in the pages of this journal and elsewhere,'Man is now in the unique position of being able consciously to control his own future evolution. Since he is the dominant biological species, this necessarily implies the ability to influence in a major way the whole pattern of biological existence. If he uses his power unwisely, the results may be wholesale destruction. To take on the burden of nature's decisions is no easy task. As is appropriate for a book with evolution as its central theme, the first chapter entitled "The Emergence of Darwinism", is a historical analysis of the development of Darwin's ideas on evolution by natural selection. Darwin, it seems, failed to recognize that Man, in contrast to other animals, has the unique capacity to transmit cumulative 'experience from one generation to the next through his development of the written and spoken language. He is thus able to accumulate not only hereditary infor- mation by the relatively slow process of natural selection, but also "cultural" information by the much more rapid process of direct acquisition, 2. by the spoken and written word>of the information accumulated by his forefathers. It is not clear why Huxley considers this cultural or psychosocial evolution as nonbiological. Man is, after all, still a part of the biological world. These special features of human evolution are further emphasized in a discussion of what is meant by higher and lower organisms. The evolutionary development of the mind is clearly the major single factor which has resulted in Man having this unique capacity for rapid cultural evolution. Here, as elsewhere in the book when discussing ethology or the . science of animal behavior (particularly.in birds), Huxley points out clearly those aspects of human behavior which are not unique to the 1 species. Man has inherited components of behavior as do other animals. However, the hereditary program for his brain (computer) must occupy a I? ,