Coefficients of determination (R2) and Akaike information criterions (AIC) of the best SAR models.

There were 8, 16 and 32 possible SAR models for tropical, temperate and total genus diversity, respectively (see S5 Table). For each biogeographical group, the ΔAICc compares the best model (ΔAICc = 0) with all of models generated, and any models with a ΔAICc of less than two in comparison with the best model were considered an equally good fit to the data.