What makes this volume by the distinguished Kenyan paleoanthropologist and coauthor of Origins (1977) and Origins Reconsidered (LJ 9/1/92) particularly engaging is the lucid presentation and interpretation of recent findings and current issues in human evolution, all of which are woven into the story of human origins. Leakey attempts to explain what he holds to be the four big evolutionary events, all foci of scientific disputation: the evolution of bipedal locomotion in apelike primates, proliferation of species of the human family (the hominids), expansion of the brain with the evolution of the genus Homo, and evolution of modern humans. Leakey argues that complex social behavior-and not the use of tools and weapons-acted as the principal driving force in human evolution. Although the sections on the origins of the hominids and Homo seem the most cogent, discussions of the evolution of art, language, and consciousness are both informative and thought-provoking. Strongly recommended for general science collections.