Many short-term experiments have demonstrated the potential impacts of ocean warming and acidification on marine organisms. However, longer-term experiments are needed to test the capacity for acclimation and adaptation to these stressors. In this talk I will describe experiments being used to test the effects of elevated temperature and CO2 levels on coral reef fishes and explore their capacity for acclimation and adaptation. These same experiments are being coupled with modern molecular approaches to understand the mechanisms underlying phenotypic responses to warming and acidification. Our results indicate that exposure to higher temperatures during early life can induce beneficial developmental plasticity that improves performance at higher temperatures later in life. Parental and multigenerational exposure to elevated temperatures can have further beneficial effects on the performance of fish at higher temperatures, both through transgenerational plasticity and the presence of heritable genetic variation. However, there are limits to these beneficial effects and challenges remain in deciphering the mechanisms involved in adaptive responses across generations. While these results offer some hope for reef fishes in a warming climate, they are undermined by the degradation of coral reef habitat that is already occurring due to climate change. Reef fishes may be able to cope with a moderate increase in water temperature, but they will be severely impacted by the loss of coral habitats and changes in the physical structure of reefs induced by climate change, which will have further compounding affects on adaptive responses to climate change in fish populations.
Professor Philip Munday has broad interests in the ecology and evolution of reef fishes. His primary research focuses on predicting the impacts that climate change and ocean acidification will have on populations and communities of marine fishes, both directly through changes in the physical environment and indirectly through effects on coral reef habitat. Using a range of laboratory and field-based experiments the research group he leads is investigating the effects of climate change on fish populations and testing their capacity for acclimation and adaptation to a rapidly changing environment.