Meeting Abstract
Anthropogenic climate change and invasive species represent two of the most feared threats to our planet’s biodiversity. Typically, these stressors are studied in isolation, but their interaction may profoundly impact native species in unanticipated ways. For example, invasive species by definition have successfully adapted to novel environments, and may therefore be particularly resilient to future environmental change. Climate change, then, may tip the balance in favor of invasive species over the native species with whom they compete. We examined the evolutionary potential of the harlequin ladybug (Harmonia axyridis), a predatory, globally-invasive beetle that competes with native species in South Africa and elsewhere. We measured the thermal sensitivity of walking speed in over 500 third generation captive-reared individuals and estimated the genetic architecture (heritabilities and genetic correlations) of parameters that define the shape of the thermal performance curve. We discuss the implications of our results for competitive interactions between H. axyridis and native beetles as the climate in South Africa continues to become hotter and drier. More generally, we discuss the role of evolutionary adaptation in facilitating invasion and changing the competitive dynamics between native and alien species around the globe.
