Apparent stabilizing selection explains micro and macroevolution of Drosophila wings

Abstract

Evolution over deep time is often slow relative to neutral or directional expectations. A striking example is provided by Drosophila wing shape, which shows substantial genetic variance yet comparatively little macroevolutionary change. Using a large-scale fitness assay, we find pervasive stabilizing selection across dimensions of D. melanogaster wing shape that is proportional to standing variation, driven by variance in male fitness, and likely generated by pleiotropy. Parameterizing a macroevolutionary Ornstein-Uhlenbeck model using our selection estimate recapitulates observed among species variance under reasonable effective population sizes, suggesting a role for apparent stabilizing selection in constraining wing shape evolution over deep time.