Fig. 7

Histograms of Schoener’s D and predicted suitability as a function of latitude. a Histograms of Schoener’s D null distributions obtained from ENMtools background test for Lissotriton vulgaris meridionalis (red) and L. italicus (blue), compared with the observed niche overlap value (black arrow). Small lines with dots represent the 95th percentile of the null distribution densities for L. v. meridionalis (in red) and L. italicus (in blue); b predicted suitability as a function of the latitudinal gradient spanning the study area