June 11, 2012

Geographic orientation and cultural homogeneity

Excellent coverage of this article at Nature News:
The researchers found that if a country had a greater east–west axis than a north–south one, the less likely it was for its indigenous languages to persist. The relationship isn't straightforward, but the model suggests that Mongolia, which is about twice as wide as it is tall, would have 5% fewer indigenous languages than Angola, which is roughly square. Meanwhile, Peru — about twice as tall as it is wide — would be predicted to have 5% more persistent languages than Angola. The result, say the authors, supports Diamond's theory because it indicates that east–west countries have more homogeneous cultures.

PNAS doi: 10.1073/pnas.1205338109

Geographic axes and the persistence of cultural diversity

David D. Laitin et al.

Jared Diamond’s Guns, Germs, and Steel [Diamond J, (1997) Guns, Germs, and Steel (WW Norton, NY)] has provided a scientific foundation for answering basic questions, such as why Eurasians colonized the global South and not the other way around, and why there is so much variance in economic development across the globe. Diamond’s explanatory variables are: (i) the susceptibility of local wild plants to be developed for self-sufficient agriculture; (ii) the domesticability of large wild animals for food, transport, and agricultural production; and (iii) the relative lengths of the axes of continents with implications for the spread of human populations and technologies. This third “continental axis” thesis is the most difficult of Diamond’s several explanatory factors to test, given that the number of continents are too few for statistical analysis. This article provides a test of one observable implication of this thesis, namely that linguistic diversity should be more persistent to the degree that a geographic area is oriented more north-south than east-west. Using both modern states and artificial geographic entities as the units of analysis, the results provide significant confirmation of the relationship between geographic orientation and cultural homogenization. Beyond providing empirical support for one observable implication of the continental axis theory, these results have important implications for understanding the roots of cultural diversity, which is an important determinant of economic growth, public goods provision, local violence, and social trust.



Ezr said...

I'm not sure the authors understand Diamond's thesis. IIRC, his theory on continental east-west spans concerns large scale climate/vegetation differences, and these obviously vary more at the "macro" (continent-sized) level. It is not applicable to the micro-level at all, since a mid-sized country will typically have very few climatic differences going either east-west or north-south; in this case, e.g., orography usually counts more than cardinal directions. Also, language extinction processes can happen at a much quicker pace than the differences in economic development the book describes - and so, again, they try to apply a "macro" model to "micro" processes, which is not what is was designed for in the first place.

Roy said...

Would be interested to see what 'artificial geographic entities' they conjured up for this as http://www.ethnologue.com/country_index.asp clearly suggests the exact opposite.

Bob said...

This souns a little bit correlating the cock crowing with the sun rising