CAT and cancer: Although these functions make CAT and CDH1 intriguing examples of genes that have potentially evolved to enhance bat cancer resistance, previous studies have also found a signal for selection in CAT (Enard et al. 2016; Slodkowicz and Goldman 2020) and CDH1 (Enard et al. 2016; Vicens and Posada 2018; Slodkowicz and Goldman 2020) in other mammals.