Nature versus nurture in social insect caste differentiation

*[Recent evidence for genetic effects on royal & worker caste differentiation from diverse social insect taxa has put an end to the view that these phenotypes stem solely from a developmental switch controlled by environmental factors. Instead, the relative influences of genotypic & environmental effects on caste vary among species, ranging from largely environmentally controlled phenotypes to almost purely genetic systems. Disentangling the selective forces that generate variation for caste predisposition will require characterizing the genetic mechanisms underlying this variation, & identifying particular life-history strategies & kin structures associated with strong genetic effects on caste.]