I have a broad interest in host-parasite ecology and evolution. My current interest focuses on how parasites switch between host species, what factors affect the ability of parasites to successfully host shift and how these may be important for the emergence of novel pathogens. I am also interested in the evolution and ecology of vertically transmitted parasites and how they spread through new host species or populations. I use insects and their natural viruses to examine these questions, in particular the Drosophila-sigma virus system."