How much trouble can an unassuming black beetle no bigger than your fingernail be? Plenty, as we learn in this episode of One Species at a Time. Tiny stowaways like the European Gazelle beetle are arriving on container ships and wreaking havoc with native ecosystems. Long-standing pests like the gypsy moth have been joined by new exotic species that are crowding out North American fauna. Ari Daniel Shapiro journeys to the forests of Oregon to meet the beetles.