Data from: Epigenetic mutations can both help and hinder adaptive evolution

Epigenetic variation is being integrated into our understanding of
adaptation, yet we lack models on how epigenetic mutations affect
evolution that includes de novo genetic change. We model the effects of
epigenetic mutations on the dynamics and endpoints of adaptive walks-a
process where a series of beneficial mutations move a population towards a
fitness optimum. We use an individual-based model of an asexual
population, where mutational effects are drawn from Fisher's
geometric model. We find cases where epigenetic mutations speed adaptation
or result in populations with higher fitness. However, we also find cases
where they slow adaptation or result in populations with lower fitness.
The effect of epigenetic mutations on adaptive walks depends crucially on
their stability and fitness effects relative to genetic mutations, with
small-effect epigenetic mutations generally speeding adaptation, and
epigenetic mutations with the same fitness effects as genetic mutations
slowing adaptation. Our work reveals a complex relationship between
epigenetic mutations and natural selection and highlights the need for
empirical data.