A structural model of the transition to agriculture

I develop a model of the transition to agriculture that can be estimated using cross-cultural data on the incidence of agriculture. The model allows for endogenous growth effects in which population density and technological sophistication are symbiotically related, and also allows for technological spillovers from centers of civilization. The model describes conditions under which population density and technological sophistication are likely to cause a switch to agriculture. Results suggest that endogenous growth affects are absent among hunter gatherers, but that technological spillovers are important in generating a switch to agriculture, and in generating technological change. Technology appears to diffuse more slowly along the north-south axis than along the east-west axis. Among agricultural peoples, endogenous growth effects appear to be present and important-a society that is 10% more technologically sophisticated has a population density about 5% larger, and a society with a 10% higher population density is on average 5% more technologically sophisticated. Hunter-gatherer population density appears to be independent of technology, but elastic with respect to environmental factors such as rainfall and habitat diversity.