An expansion of the demographic transition model: the dynamic link between agricultural productivity and population

Russell Hopfenberg expands on the traditional demographic transition model by considering a longer time frame and incorporating the critical factor of agricultural productivity.

ABSTRACT: The classic demographic transition model illustrates the pattern of birth and death rates over time, shifting from high and equivalent to low and equivalent, with population increasing sharply during this transition as a society industrialises. However, the model has a limited temporal frame and cultural scope. It also overlooks that human population trends follow agricultural productivity. Because food is an essential carrying capacity variable and a fundamental economic driver, as food availability is increased the population increases leading to severe biodiversity loss. The current analysis expands the classic model, taking into account all of human history, and highlighting the basic carrying capacity foundations of fertility changes. This comprehensive model shows birth and death rates in Stage A as low and equivalent before the advent of the agricultural revolution. Stage A is followed by Stages B and C, in which the increasing birth rate precedes the increasing death rate, causing a rise in population. The stages then progress as in the classic demographic transition model.