Evidence for plant epigenetic response to selection

Natural selection shapes the size and reproduction of organisms harbouring genetic variation. Transgenerational epigenetic variation exists for these traits and theory predicts that selection can rest on such heritable variation. Remarkably, this prediction has not previously been tested although the evolutionary significance of epigenetic variation is hotly debated. Here, we found an epigenetic signature of selection in experimental Arabidopsis thaliana populations of epigenetic variants called epiRILs harbouring almost identical DNA sequences but differential methylation regions.