Population genetics. Much of my research in this field has concentrated on measuring inbeeding depression and heterosis in wild populations. I developed a microsatellite-based measure to examine the effects of inbreeding on life history traits in wild populations and demonstrated inbreeding depression is widespread in wild vertebrate populations. I have also worked on genetic by environment effects on demography.

Evolutionary ecology. My research in this field has explored adaptive birth sex ratio varation in Soay sheep and plasmodium and the immunological response to co-infection. My current focus is on linking individual-level demography to population level dynamics to estimate opportunities for selection, selection and responses to selection.

Conservation and management. Good conservation biology and population management recommendations should be based on ecological and genetic theory. Often they are not. My research in this area has focused on how a solid ecological understanding can be used to underpin the conservation and management decision-making process.