Scientists have long attempted to discover why animals rarely live alone. Animal society seems to be based on despotic rule by the strongest, tempered by the powerful attractive forces of sex. Portrayals of Thorlief Schjelderup-Ebbe, Solly Zuckerman,... (more) Clarence Ray Carpenter, Frank Fraser Darling, William Hamilton, and Amotz Zahavi, show the contributions of each of these men towards understanding the puzzle.