Nature-nurture in the twenty-first century

Environments are not just the physical environment but also the biotic and social environments provided by other individuals, which have emerge as key factors shaping behaviour and the effects of behaviour. As these latter environments are highly dynamic, continually changing and evolving, this form of gene-environment interaction (GxE) is also always shifting and thus contributes to the substantial variability observed in behaviour. The study of GxE, including indirect genetic effects, has been extended in the last decade to include feedback loops between genes and the environment based on the realization that organisms modify the environment in which they live and that in turn this modification alters selection acting on the organism. Eco-evolutionary dynamics is becoming an emerging field in evolutionary ecology, especially as this can occur at much shorter time scales than 'classic' evolutionary change.