Fig. 1

Global distribution of language diversity. Left panel: values on a logarithmic scale of number of languages are shown for 200 × 200 km cells of an equal-area grid. Right panel: correlation in language diversity between each pair of grid cells owing to spatial autocorrelation and phylogenetic relatedness. Correlation coefficient is estimated from our generalized least squares model that includes all the climatic and landscape variables as predictors (see Methods). Correlated grid cells are roughly clustered into nine geographic regions, so we color code the rows and columns by these regions. Grid cells within East Asia, Europe, and the Americas are more autocorrelated than grid cells within the other regions