ABSTRACT
Some introduced species thrive a little too well in their new habitat, where they become destructive to the ecosystem. These invasive species can threaten the existence of native species. We begin with two case examples: first, cane toads that are destructive in Australia and in Florida, and then large mice that are threatening birds on Gough Island and other islands in the South Atlantic. We then turn to the general features of invasive species and the threats they pose. Can we predict which introduced species are likely to become invasive? Progress in addressing this question has been largely elusive; however, a few common suggestive themes have emerged. For instance, invasive plants tend to have small genomes and rapid growth. Native species can respond to threats from invasive species: for instance, soapberry bugs have evolved larger beaks in response to an invasive weed outcompeting the native plants. We conclude with a discussion of an invasive fungus that has been a major factor in the decline of amphibians.
