There is a fascinating new NBER paper out making the case for the humble potato as disruptive innovation:
We have estimated the effect of the introduction of the potato on Old World population growth and urbanization. The nutritional and caloric superiority of the potato, and its diffusion from the New World to the Old, allows us to estimate causal effects using a difference-in-differences estimation strategy. According to our most conservative estimates, the introduction of the potato explains 22% of the observed post-1700 increase in population growth. These results show that food and nutrition matter. By increasing the nutritional carrying capacity of land they can have large effects on population.
To the extent that urbanization serves as a measure of the shift from rural agriculture to urban manufacturing, our estimates also provide historic evidence of the importance of agricultural productivity for economic development. According to our estimates, the introduction of the potato explains 47% of the post-1700 increase in the average urbanization rate. Our estimates suggest that increased agricultural productivity can play a signi?cant part in promoting the rise of urban centers, industry, and economic development. [Emphasis mine]
Assuming these numbers are even close to being correct, they are astonishing gains indeed.
Nathan Nunn and Nancy Qian, “The Potato’s Contribution to Population and Urbanization: Evidence from an Historical Experiment,” National Bureau of Economic Research Working Paper Series No. 15157 (July 2009), http://www.nber.org/papers/w15157.
[Update] My ever-eclectic Kauffman colleague Dane Stangler has even earlier musings on the same spud subject.