A role for epigenetic adaption in evolution

The outcome of epigenetic responses to stress depends strictly on genetic background, suggesting that altered phenotypes, when induced, are created by a combination of induced epigenetic factors and pre‐existing allelic ones. When individuals with altered phenotypes are selected and subjected to successive breeding, alleles that potentiate epigenetic responses could accumulate in offspring populations. It is reasonable to suppose that many, if not all, of these allelic genes could also be involved in creating new phenotypes under nonstressful conditions. In this review, I discuss the possibility that the accumulation of such alleles in selected individuals with an epigenetic phenotype could give rise to individuals that exhibit the same phenotype even in the absence of stress.