What do such words as "information," "displacement," and "courtship" mean to the growing ranks of ethologists who study animal behavior? Like all sciences, ethology has accumulated its own set of concepts and terms, taken from everyday language, borrowed from neighboring disciplines, or coined especially to describe novel ideas and phenomena. Klaus Immelmann and Colin Beer have responded to the acute need for an authoritative dictionary of ethology with this valuable guide to the world of animal behavior. The authors present a balance of historical, enduring, and current terminology, providing clear and concise definitions of the terms central to ethological writing. They give special treatment to terms from related disciplines, particularly evolutionary biology, physiology, ecology, and sociobiology, and to controversial concepts such as "instinct," "motivation," and "imprinting." For words like these, the authors take pains to explain the nature of the problem, to distinguish differences of meaning, and to chart the range of application. A preponderance of terms relate to the behavior of higher vertebrates, especially mammals and birds, since these animals supply a high proportion of ethology's basic ideas and technical concepts. Representing the culmination of two decades of assiduous scholarship, this book will be immensely useful to neophyte and professional alike.