For most of the time that anatomically modern humans have existed, small mobile foraging bands followed natural resources. Starting around 15,000 years ago, communities of sedentary foragers began to emerge. This transition has been detected archeologically in numerous regions of the world, including southwest Asia and Japan. In these cases and others, the transition to sedentary foraging occurred several millennia before the transition to agriculture. We develop an economic model of this process that combines climate change, population growth, and technical progress. Better climate led to a larger population for Malthusian reasons, and in some cases this led to technological innovation. A novel insight from our theory is that technological change caused a ratchet effect that made sedentism persist even in cases where climate subsequently deteriorated. (C) 2015 Elsevier B.V. All rights reserved.
