Most anthropologists agree that a comprehension of adaptation and adaptive processes is central to an understanding of human biological and behavioural systems. However, there is little agreement among archaeologists, cultural anthropologists, and human biologists as to what adaptation means and how it should be analyzed. Because of this lack of a common underlying theory, method, and perspective, the subdisciplines have tended to move apart, and anthropology is no longer the integrated science envisaged at its inception in the nineteenth century. In this book, the authors-both biological and cultural anthropologists-use a common theoretical framework based on recent evolutionary, ecological, and anthropological theory in their analyses of biological and social adaptive systems. Although a synthesis of the subdisciplines of anthropology lies somewhere in the future, the original essays in this volume are a first attempt at a unified perspective.