What drives species distributions? What poses limits to current species distributions? And how will climate change impact future distributions and species survival? These are some of the questions I am interested in. Working across the Drosophila species complex, and native bees, I use a number of approaches (quantitative genetics, comparative phylogenetics and physiology) to answer my research questions.
Drosophila as a model
I use Drosophila as a model for understanding the processes that shape trait variation and to determine whether species differ in their capacity to adapt to environmental change. I have shown the presence of fundamental limits in ecologically important traits in restricted tropical Drosophila species; I have tracked evolutionary changes and limits of cold and desiccation resistance across the Drosophila phylogeny and found signatures of phylogenetic constraints in heat resistance (critical thermal maxima). This result suggests most Drosophila species may have reached a physiological limit for heat resistance.
I am also interested in the extent to which phenotypic plasticity can buffer species from environmental change and whether there is evidence for climatic variability driving the evolution in plasticity for stress-related traits. My research in ~40 Drosophila species has found limited evidence for the climatic variability hypothesis in desiccation plasticity.
Australia has a diverse bee fauna comprised mostly of solitary bees. Despite the fact native bees play an essential role in providing ecosystem services, we know very little about the capacity of bees to adapt to climate change. Using similar approaches to studying thermal adaptation in Drosophila here we ask, what environmental variables shape the distribution of Australian native bees? How does thermal tolerance vary across native bee species? And what is the contribution of genetics and environment to thermal resilience in native bees?
Fiji is home to a small group of Homalictus native bees. Originally there were thought to be only four species but recent studies have shown that in fact there are over 20 species. Interestingly all but one of these species is restricted to the highlands. What are the environmental drivers that limit the distribution of most of these native bees species and how will climate change impact the biodiversity of these native bees?
I am interested in a broad range of evolutionary questions with my work also touching on canalization, the evolution of longevity and correlated trait evolution.
Make shift lab in the field