Abstract:
:Human languages show a remarkable degree of variation in the area they cover. However, the factors governing the distribution of human cultural groups such as languages are not well understood. While previous studies have examined the role of a number of environmental variables the importance of cultural factors has not been systematically addressed. Here we use a geographical information system (GIS) to integrate information about languages with environmental, ecological, and ethnographic data to test a number of hypotheses that have been proposed to explain the global distribution of languages. We show that the degree of political complexity and type of subsistence strategy exhibited by societies are important predictors of the area covered by a language. Political complexity is also strongly associated with the latitudinal gradient in language area, whereas subsistence strategy is not. We argue that a process of cultural group selection favoring more complex societies may have been important in shaping the present-day global distribution of language diversity.
journal_name
Proc Natl Acad Sci U S Aauthors
Currie TE,Mace Rdoi
10.1073/pnas.0804698106subject
Has Abstractpub_date
2009-05-05 00:00:00pages
7339-44issue
18eissn
0027-8424issn
1091-6490pii
0804698106journal_volume
106pub_type
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