Did Technology Transfer More Rapidly East-West than North-South?

We offer evidence of the role of continental orientation in the historical diffusion of technologies. Diamond (1997) argued that technologies spread more slowly North-South than East-West for two reasons. First, it was relatively costly for individuals to transport innovations when experiencing North-South variations in climate. Second, some innovations (e.g, selectively bred seeds) would have been less likely to survive North-South movements. Continents with East-West orientation, then, were characterized by less costly and/or more successful sharing of technologies. We employ Comin et al.'s (2010) data on ancient and early modern levels of technology adoption in a spatial econometric analysis. Historical levels of technology adoption in a (present-day) country are related to its lagged level as well as those of its neighbors. We allow the spatial effects to differ depending on whether they diffuse East-West or North-South. Consistent with the continental orientation hypothesis, East