Why do one percent of nature’s newcomers grow in numbers until they are a plague? Biologists study the resilience of the ecosystem in the face of exotic species.
As a result of globalization, plants and animals are ending up outside their original habitats, sometimes with disastrous consequences. Like the box tree moth or the Louisiana crayfish that has driven out indigenous crayfish. The original Asian tiger mosquito can transmit as many as 10 diseases, including the Zika virus and Dengue fever. New diseases and pests are continually appearing on the scene in agriculture and horticulture, from avian flu to the tomato leafminer moth. Water hyacinths are taking over ditches and ponds, nature areas are overgrown with giant hogweed and Japanese knotweed.