The history of human origins must be written in terms of four dynamic parameters: (1) the physical changes in the hominoid line which led to man; (2) the development of artifacts used by hominoids; (3) changes in hominoid behavior, with all their implications regarding modifications of his emotional and intellectual capacities; and (4) the natural ecological context within which these changes occurred. Experts on this subject have tended to concentrate attention on the first two of these four, partly because these two left the physical evidence of bone and tools on which the whole study has been built. Physical anthropologists must reconsider their assumption regarding the fourth parameter. In doing so, they may find help in some new views on the homini-predator relationship: (1) that the hominid defense against predators must have been in the area of nonphysical behavioral patterns and must have included avoidance of predators as well as the growth of cooperation and communication among men, and (2) that the phenomenon of predation in general makes it highly unlikely that man could ever have been anything more than an incidental victim of predators. As an incidental consequence of these changes in our assumptions in the areas of human behavior and natural ecology.
