Phenotypic plasticity and the emerging field of ‘invasion epigenetics’

Epigenetic variation provides an important, but complex, layer of information involving gene regulation. Epigenetic variation represents various biochemical modifications of the genetic code (DNA) that influence gene expression, best known for its role in governing plastic responses to changing environmental conditions. This chapter summarises the main epigenetic mechanisms (DNA methylation, histone modification, non-coding RNAs) and remarks on how these may influence the ecological and evolutionary dynamics of organisms. The chapter then takes a closer look at examples involving invasive species to synthesise current knowledge on the role of epigenetic variation during different stages of invasion. The compensatory role of epigenetic variation in the performance of invasive species with no or low genetic diversity is discussed, in particular in relation to stress conditions. The chapter also briefly discusses the link between hybridisation and genome doubling (i.e. polyploidization) and epigenetic remodelling.