Genomic signatures of evolutionary rescue in bats surviving white-nose syndrome

Evolutionary rescue can help populations avoid extinction after abrupt environmental change through the rapid evolution of advantageous traits that promote population growth. However, evolutionary rescue is thought to be rare in taxa with long generation times because demographic declines towards extirpation are likely to outpace the acquisition of adaptive de novo mutations. Adaptive alleles must therefore be selected from standing genetic variation, a process that leaves few detectable genomic signatures. Here, we provide the first genetic evidence for evolutionary rescue in bat populations affected by white nose syndrome (WNS). By comparing genetic samples from before and after little brown bat populations were decimated by WNS, we identified signatures of soft selection on standing genetic variation. This selection occurred at multiple loci in genes linked to hibernation behavior, suggesting that changes in hibernation have allowed these bats to survive infection with WNS. Through these findings, we show that evolutionary rescue can be a conservation-relevant process even in slowly reproducing taxa facing extinction.