Argues that a thorough understanding of factors that influence aggression in children cannot be achieved without including behavior genetic studies that allow examination of the effects of shared versus non-shared environment, as well as genes, on aggressive behaviors. Details the growing body of evidence on the genetic effects on aggression.…

This report summarizes preliminary results from a behavioral study of 13 male infants who were ascertained to have an XX Y sex chromosome complement at birth and who are being followed longitudinally through early ontogenesis. (CM)

Much of our thinking about contemporary social problems reflects tacit presuppositions regarding the operation of heredity and environment in human behavior. These beliefs have important implications for practical decisions. Advances in genetics, psychology, anthropology, and other disciplines have contributed much to a clarification of the…