The Impact of Farming on Expansion of Human Populations

Abstract

In the history of humanity there must have been many critical times in which new technological advances made possible increased population growth, higher population density, or greater chances of successful migration and therefore stimulated growth and expansion of specific populations. Among them, the beginnings of domestication of plants and animals must have had paramount importance, and new important additions to the list of domesticates must have had their own influence. Other technological developments: tools, means of transportation or for waging war may also have contributed in important ways. Population growth, once started, tends to proceed by inertia and gets close to, or even above, the limits set by the carrying capacity of the land. It will then, if at all possible, stimulate migration to occupy new places near or far, depending on means of transportation. Thus in the long run important technological developments have stimulated not only growth but also migration that will continue until boundaries too difficult to surpass are reached. In a recent book with Ammerman (1984) we have shown how the economy based on plant and animal domesticates, arisen in the Middle East, was exported to a very large surrounding area by the slow migration of the neolithic people themselves, continuing over millennia, and not simply or uniquely by stimulus diffusion. The reason behind this conclusion will be illustrated. Other examples of demic diffusion worth considering that are presumably stimulated by agricultural developments are the spread of Bantu speakers to Central and South Africa, and the spread of several waves of neolithic people from China and S.E. Asia to the Pacific islands.