Get smart: native mammal develops toad-smart behavior in response to a toxic invader

Although invasive species can cause major declines in native populations, some individuals in a native population are better equipped to deal with the threat than others. Existing trait variation—especially in highly flexible behavioral traits—may thus buffer populations and allow natural selection to proceed. Cane toads (Rhinella marina) have caused dramatic declines in native Australian predators, which unwittingly attack the poisonous toads. The northern quoll (Dasyurus hallucatus) is one such predator, with declines and local extinction of quoll populations typically occurring rapidly after toads arrive. Despite this, some quoll populations persist in areas where toads have been present for ≥70 years. Here, we compare northern quolls from toad-infested and toad-free areas to test whether this persistence is enabled by behavioral traits. We demonstrate that northern quolls from long-term toad-infested areas have indeed become “toad-smart,” spending significantly less time investigati...