Table 2: The relative contribution (%) of geographic and environmental predictor variables to Speyeria atlantis , northernS. hesperis , and southern S. hesperis ecological niche models (ENMs). Geographic predictor variables included terrain ruggedness, heat load (based on terrain slope and aspect), and land cover (12 categories). Environmental predictor variables included mean temperature of the coldest month, mean temperature of the warmest month, the difference between mean temperatures of the coldest and warmest months (continentality), degree-days below 0°C (chilling degree days), degree-days above 5°C (growing degree days), extreme minimum temperature, precipitation as snow, and summer (Jun to Aug) precipitation. Relative contribution was measured as the drop in AUC values after each variable was randomly permuted. For each of the three lineages, five ENMs were built, each withholding a different 20% of occurrence localities used for model evaluation. The mean and standard deviation (s.e.) of relative contributions for each predictor variable across the five ENMs are reported.