The book reflects the main directions in which the science of animal behavior is developing: research into the mechanisms of learning, work on instinctive behavior, group, sexual, parental behavior, genetics of behavior, etc. The undoubted advantage of the book is the systematic and completeness of the presentation. Written from the perspective of evolutionism, it allows us to trace the behavioral characteristics of animals from their lower representatives to mammals inclusive. Intended for students and teachers of universities and pedagogical institutes, as well as for a wide range of readers interested in the life of animals.