The interface of organismal physiology and community and ecosystem ecology. I have worked on mathematical models to describe a range of biological phenomena including broad-scale biodiversity gradients, rates of DNA evolution, and nutrient cycles in organisms and ecosystems. My current work is funded by the Australian Research Council. It entails developing and testing a new class of biodiversity models that relate contemporary biodiversity to speciation-extinction dynamics in the fossil record and ecologically induced changes in population abundance through time. This work aims to provide a better understanding of how environmental changes, including those induced by human activities, influence the numbers of species present in ecosystems
