Populations of common midwife toads (Alytes obstetricans) in the Pyrenees have survived outbreaks of Batrachochytrium dendrobatidis, the fungal disease responsible for more vertebrate species extinctions than any other infectious disease in recorded history. Surviving toads secrete antimicrobial peptides from their skin unusually early, during the tadpole phase, giving them protection precisely when the transition to keratin-bearing adult skin makes them most vulnerable to th