Fig. 2

Results of structural equation models examining the direct and indirect effects of mean annual temperature (MAT), mean annual precipitation (MAP), glacial-interglacial velocity in MAT (Velo MAT), campus population density (Population) and age (Age), and plant species richness (Plant SR) on bird species richness (Bird SR, a), phylogenetic structure (Phylo NRI, b), and functional structure (Funct NRI, c). Standardized regression coefficients were given, and the strength of the effects was proportional to line width. *p < 0.05, **p < 0.01