Largely rewritten and containing many new illustrations, the latest edition of this text incorporates updated classifications as well as new information on many subjects, especially in the areas of endocrinology and neurology. Retaining the systematic arrangement of earlier editions, the text now also contains a readable two-column format. Detailed descriptions of basic anatomy make the book a good reference for dissectionists of fish, frogs, birds, and mammals. In addition, the author reviews controversial topics such as the origin of chordates, punctuational evolutionary changes, and the nature of progress in evolution, providing analyses and comparisons of the homeostatic capacities and evolutionary potential of the various groups of vertebrates.