This uniquely integrative volume brings together leading experts in developmental psychology and animal behavior to provide a new perspective on the nature and functions of play. In an introductory chapter, distinguished ethologist Patrick Bateson describes how youthful exploration and games contribute to both individual development and group survival--not only in humans, but in other species as well. Parallel chapters then examine social play, object play, and pretend play in humans and great apes, providing a broader context for understanding why human children behave the way they do. While much of the knowledge on human play comes from industrialized Western societies, the book also features important chapters on hunter-gatherer and pastoral cultures. Throughout, a rich array of black-and-white photographs and other illustrations enliven this authoritative work.