Table 3: List of environmental variables used in our analyses.

Data RecordInstrumentEcological attributesVariables derived

Normalized Difference Vegetation Index (NDVI)Satellite-MODISVegetation densityNDVI mean
Vegetation Continuous Field (VCF)Satellite-MODISForest cover + heterogeneityTree cover
Scatterometer-Backscatter*†Satellite-QSCATSurface moisture + roughness (forest structure), seasonalityQSCAT aug
DEM*SpaceShuttle SRTMTopography + ruggednessSRTM
WorldClimStation-NetworkBioclimatic variablesBio1, Bio2, Bio10, Bio11, Bio12, Bio15, Bio17, Bio18

*Data at native resolutions smaller or larger than 1 km have been aggregated to 1 km.
QSCAT is based on data from 2001.
§Based on MODIS data from 2001 [41].
WorldClim data are based on monthly climatologies from 1950–2000 [39]. The bioclimatic variables are annual mean temperature (Bio1), mean diurnal temperature range (Bio2), mean temperature of the warmest quarter (Bio10), mean temperature of the coldest quarter (Bio11), annual precipitation (Bio12), precipitation seasonality (Bio15), precipitation of the wettest quarter (Bio17), and precipitation of the warmest quarter (Bio18).