Still, about 500 years ago, Tasmanian devils became extinct on the Australian continent, probably due to dingoes and humans. If they were permitted to vanish entirely, it would profoundly affect the island’s ecology. The flesh-eating marsupials keep the cat and fox population in check. No more devils would mean a spike in the number of those predators, which would spell the extinction of more than a dozen other species, including some, and insects. And as scavengers, devils also remove sick and dead animals from the landscape.