World Population Growth

Abstract

The human race has a long history. Depending on which paleontologist or paleoanthropologist one consults, man's beginnings reach back from a third to more than a half million years. At the Darwin Centennial in Chicago, in November I959, anthropologist L. S. B. Leakey told of an early man or late protoman, evidence of whom has been found in East Africa, who may mark the beginnings of the species. The available skeletal material and artifacts, which were uncovered deep in the side of a canyon that afforded quite an accurate geological dating, indicate that these people were, indeed, human.1 During the next 200,000 years or more of man's rather precarious foothold on Earth, his numbers were extremely small and our knowledge of him is quite meager.2 Typically, he congregated in nomadic tribes and was completely subject to all of the vagaries of the weather and the ecological cycle of the game animals on which his existence depended. Food shortages were usually endemic, and the ravages of epidemics were routine-although the wide dispersal of the population tended to localize these hazards. Nevertheless, the picture that emerges is one in which births and deaths were roughly balanced, with births perhaps holding a narrow margin. Despite the rigors of life, however, many island civilizations of a high cultural level prospered for a time in the rich river valleys of Egypt and Asia and then vanished. Populations apparently grew rapidly during the emergence of a golden age, and then declined during the following period of regression and decay. In the most varied contexts, this cycle of growth and decline appears to have been repeated for millennia. Even in China, the location of a man's most stable culture, this seems to have been the recurrent pattern. In any event, the competent consensus is that by the time of Christ, near the midpoint in the cycle of growth and decline of the Roman Empire, the population