My research group usually consists of 4-6 PhD students and 5-8 post-docs. We work at the interface between behavioural ecology, population dynamics and evolutionary biology. We currently work in three main areas: (1) The evolution of vertebrate breeding systems Current studies are investigating the division of labour and the evolution of cooperation in social mongooses; the evolution of leks in mammals and birds; and the functional significance of variation in parental care in fish. (2) Population regulation and the control of population stability in large mammals Long-term studies in red deer (on Rum), Soay sheep (on St Kilda) and suricates (southern Kalahari) are examining the ecological factors generating stability and instability in populations; the effects of early development on adult success and survival; asymmetries in competition between the sexes; and the effects of different management regimes on ungulate populations. (3) Natural and sexual selection in natural populations We are currently using the long-term studies of red deer and sheep to investigate selection on phenotype and genotype in natural populations; the heritability of reproductive success; and the effects of variation in population density on natural and sexual selection.