Selsam has revised her 1963 introduction to the social life of animals in order to take into account the field observations of Schaller, Goodall, and Iain Douglas-Hamilton (on elephants); the investigation of pheromones in insects; and other important studies conducted in the interim between editions. The bulk of the book remains as before, most of the changes being in the nature of insertions and additions--with an occasional correction of earlier misconception (e.g., ""A pack of wolves was once thought to consist of only two parents and their offspring, but recent work shows that many packs have several extra adults that may also breed';). To accommodate the new information, the final section on relationships among species (a whole different subject anyway) has been dropped. Another change for the better and brighter is the substitution of black-and-white photos for Elgin's lackluster drawings. Well worth the update.