The profound effect of body temperature on physiology can have a major impact on the ecology and survival of organisms. Consequently, global climate warming may have manifold biological repercussions. However, the effects of climate warming might be ameliorated if evolution can quickly alter the thermal sensitivity of fast-breeding organisms such as insects. This project will use two different approaches to study experimentally how fruit flies respond evolutionary to simulated climate change in the laboratory. The first approach uses an efficient new technique that enables us to breed flies that are very resistant to periodic exposure to heat or cold or both. This approach involves monitoring physiological divergence in stocks of flies that have already been evolving at different temperatures for several years. This study will monitor how quickly physiology responds evolutionarily to a sustained shift in (non-extreme) temperatures. Using both sets of flies, we will determine how quickly the sensitivity of physiology to temperature can evolve as well as any important side effects (life history, resistance to other studies will have direct implications for projection models of how insect populations will respond to global climate warming.
