“…The distinction is complex, since phenotypic plasticity is genetically based but also underlain by epigenetic mechanisms that can be independent of genetic differences (Richards et al, 2006(Richards et al, , 2010(Richards et al, , 2017Cortijo et al, 2014;Banta and Richards, 2018). Furthermore, the molecular-level mechanisms that contribute to such plastic responses can ultimately lead to genetic changes or non-genetic inheritance (West-Eberhard, 1989;Day, 2009, 2018;Klironomos et al, 2013;Kronholm and Collins, 2016;Kronholm et al, 2017;Wölfl et al, 2020). A particularly striking example of the disconnect between genetic variation and heritable phenotypic response is in the single octoploid clone of Japanese knotweed that has spread aggressively through a broad range of habitats in temperate Europe and North America (Beerling et al, 1994;Bailey and Conolly, 2000;Grimsby et al, 2007;Gerber et al, 2008;Bailey et al, 2009;Richards et al, 2012;Zhang et al, 2016).…”