Most, if not all, organisms possess the ability to alter their phenotype in direct response to changes in their environment, a phenomenon known as phenotypic plasticity. Selection can break this environmental sensitivity, however, and cause a formerly environmentally induced trait to evolve to become fixed through a process called genetic assimilation. Characterizing the proximate mechanisms that underlie genetic assimilation may advance our basic understanding of how novel traits and species evolve.
Here, Ehrenreich and Pfennig discuss the potential role of genetic assimilation in evolution, and propose genetic and molecular mechanisms that might facilitate the process.
Ian M. Ehrenreich, David W. Pfennig, 2015, 'Genetic assimilation: a review of its potential proximate causes and evolutionary consequences', Annals of Botany, vol. 117, no. 5, pp. 769-779 http://dx.doi.org/10.1093/aob/mcv130