Table 1.

Results of the main hypotheses tested in this study, from ordinary least-squares regression (OLS) and PGLS. TNB and PNB are temperature niche breadth and precipitation niche breadth, respectively. Values of r² are adjusted for multiple variables.

variables	r2	p-value
OLS
TNB versus mean annual temperature	0.240	<2.2−16
PNB versus annual precipitation	0.144	<2.2−16
TNB versus distance from midpoint temperature	0.152	<2.2−16
PNB versus distance from midpoint precipitation	0.144	<2.2−16
TNB versus PNB	0.066	<2.2−16
PGLS
TNB versus mean annual temperature	0.120	<2.2−16
PNB versus annual precipitation	0.116	<2.2−16
TNB versus distance from midpoint temperature	0.049	<2.2−16
PNB versus distance from midpoint precipitation	0.082	<2.2−16
TNB versus PNB	0.202	<2.2−16