Featuring in-depth contributions from an international team of experts, the Biology of Turtles provides the first comprehensive review of the Testudinata. The book starts with the premise that the structure of turtles is particularly interesting and best understood within the context of their development, novelty, functional diversity, and evolution. It provides a robust discussion of the development and diversity of the shell. The book also explores the turtle body plan, its physiological and ecological consequences, evolutionary novelties, and their importance. The 200 illustrations found throughout the text enhance the chapters combine with color illustrations of the development of the shell, aspects of bone structural diversity, growth, and skeletochronology, to make this book an unparalleled resource. The volume concludes with a thoughtful discussion of the more than century long debate on the origins of turtles and the reasons why our understanding of the phylogenic origins and evolution of turtles remains tentative. Currently available books on this subject are woefully out of date and no overall review of Testudinata has been undertaken...until now. Each chapter represents a milestone in synthesizing a wide range of available information on specific subjects. The book's challenge: look both inside and outside the shell to build a clearer understanding of the diversity and evolution of turtles.