Figure 4. Predicted geographic distribution of Toxostoma rufum, the brown thrasher, in the continental US based on three different niche modeling experiments.

(A) All 22 variables used in the study were included in the prediction; (B) prediction based on a reduced set of 13 variables based on a UI threshold of 0.5; (C) prediction based on a reduced set of 10 variables based on a UF threshold of 0.25. Darker shades of blue reflect greater model agreement between individual models in the best subset or greater confidence in the prediction of presence of the species in those pixels.