At its heart, this work by Geary (psychological sciences, U. of Missouri) is a defense and extension of Charles Darwin's theory of sexual selection to the explanation of human sexual differences across a variety of domains. He begins by addressing the evolutionary origins of sexual reproduction, the dynamics of intrasexual competition and intersexual choice in Darwin's theory, evolution and sex differences in human developmental patterns over the life span, sexual selection in primates and during human evolution, and evolution and male investments in parenting. He then explores the key components of Darwin's theory, mating competition and choice, before turning to a review of how these components interact in producing sexual differences in human cognition; in infancy and at play; in social development; and in "folk" understandings of psychology, biology, and physics. Annotation ©2010 Book News, Inc., Portland, OR (booknews.com)