This text provides a concise introduction to the field of animalbiology. Readers discover general principles of evolution, ecology, animal bodyplans, and classification and systematics. After these introductory chapters,readers delve into the biology of all groups of animals. The basic features ofeach group are discussed, along with evolutionary relationships among groupmembers. Chapter highlights include newly discovered features of animals asthey relate to ecology, conservation biology, and value to human society.Regular updates to the phylogenies within the book keep it current.