Research in this theme asks when, how and why selection shapes the psychology and behaviour of living organisms. This interdisciplinary research theme sits at the interface between evolutionary biology, economics, and psychology – and incorporates approaches and insights from all three. We work on a variety of human and non-human model systems, with techniques including game theoretical modelling, behavioural studies, neuroimaging, and neuroendocrinology. Specific areas of research include social evolution, developmental psychology, decision making and mental health.