Classic study of dog behavior, the authoritative information from 20 years of research at the Jackson Laboratory. Central to the book is the role heredity plays in the development of behavior. Giving puppies an environment designed on the principles of a well-run school, Scott and Fuller tested five breeds representing the major dog groups and carried out a Mendelian experiment with two of the most different breeds: The basenji and the cocker spaniel. They found that heredity affects almost every trait tested; that gender affects aggressiveness and the dominance order, but not trainability and problem-solving; that emotional traits profoundly influence performance; that, although breeds differ widely in emotional and motivational characteristics, none shows distinct superiority in problem solving; and that detailed statistical analyses indicate a highly complex pathway between primary gene action and its final effect on behavior. Includes important information on rearing methods, the origin and history of dog breeds, basic behavior patterns and the psychological and behavioral development of puppies. Originally published in 1965.