Biodiversity is in crisis. Our cities seem to have become hybrid spaces where we encounter far more animals than we do in our forests. Take, for instance, the 33,000 wild boars in Berlin's parks, the leopards on the outskirts of Bombay, or even the coyotes of Chicago and the mountain lions of Mulholland Drive. Some have adapted, behaviorally or physiologically: Brooklyn mice are resistant to heavy pollutants, Barcelona snails withstand urban heat, Manhattan swallows have shorter wingspans to dodge skyscapers, and vultures in Lima work together.