The long-awaited third edition of this popular textbook, which has been unavailable for several years, is completely revised and updated. It retains the successful format of previous editions, dealing with the nature, actions and roles of hormones among vertebrate animals. Special emphasis is placed on the evolution and origins of hormones and their receptors; the role of hormones in the physiological coordination of vertebrates; and each endocrine process in the context of the organism's physiology, ecology, and evolution. Comparative Vertebrate Endocrinology discusses the intimate physiology of the endocrine system and the pivotal role of hormones in coordinating basic body processes such as nutrition, reproduction, calcium metabolism, and osmoregulation, as well as their contributions to animal coloration, molting, and development. The species included range from lower chordates to mammals, including marsupials.