Abstract

A decade ago, a landmark edited collection of essays made official the ongoing quest for an Extended Evolutionary Synthesis (EES), beyond the classic Modern Synthesis that took shape in the 1930s and ‘40s. When Evolution – The Extended Synthesis was published, research on epigenetic inheritance was at its onset, with the theory being far ahead of the empirical results. An important book, Evolution in Four Dimensions by Eva Jablonka and Marion Lamb, articulated the notion of multiple channels of inheritance, including genetic, epigenetic, behavioral, and symbolic. These multiple modes of inheriting information within the biosphere joined a number of other empirical findings and conceptual advances to articulate the early version of the EES. In the intervening decade, our empirical understanding of epigenetic inheritance has improved, so it seems that a reevaluation of where we are and where we may possibly be going, is in order. Progress is constrained by the fact that understanding systems of inheritance requires time-consuming experimental designs that incorporate multiple generations. Further, technological limitations have yet to be overcome and most of our understanding of genome level processes is still confined to model species. In this paper we discuss what we have learned so far about epigenetic inheritance and what developments are needed to make further progress. We conclude with a discussion of the current role of epigenetic inheritance in the EES, and how it has changed in the intervening decade.