ABSTRACT
In the early 1970s a population-only explanation of anthropogenic environmental impacts was adduced, the “population bomb” (Ehrlich 1968). A discussion ensued as this model was ill-adapted to the impacts observed in afuent countries. A different explanation emerged, called IPAT, whereby impacts equal a function of population, afuence, and technology (formulated by 1972 by Commoner on the one hand and Ehrlich and Holdren on the other hand; York et al. 2002): large populations, high consumption, and low technology are posited to entail the largest encroachment on nature. While a suggestive simplication, this fails to capture the current relative weight of population impacts and future possibilities to curb population growth.
