White-nose syndrome (WNS) has had significant effects on many populations of bats, but exactly how certain populations are affected varies among species, likely based on physical, genetic, and behavioral differences. The Little brown bat (Myotis lucifugus) for example, rebounds after the initial WNS-induced mass mortality event, and shows gradual improvement each following year. The closely related species, the Indiana bat (M. sodalist), shows the opposite pattern of annual survival following infection by WNS. This trend suggests that WNS imposes strong selection for a WNS-resistant phenotype in some species, potentially allowing infected populations to revert to positive growth (a phenomenon known as “evolutionary rescue”).