The Epigenetic Evolution of Genetics (and Epigenetics)

by Shea Robison

Instead of the evolution of modern genetics and the Modern Synthesis as a progressive process of gradually narrowing in on the one true path of scientific knowledge, the history of genetics suggests that genetics could have developed along any number of alternate pathways, including paths in which epigenetics was accepted in one form or another within the theoretical edifice of modern genetics.  This description of the path-dependence of the evolution of modern genetics and the Modern Synthesis of evolutionary thought actually mirrors Waddington’s own dynamic visual metaphor of biological development as a marble on a landscape of “branching valleys with steep or gently rising sides, with cols and hanging valleys or more or less well-defined contours.”[1] Whichever particular course a marble placed on this landscape begins to roll down depends upon the initial placement of the marble and the conditions of the landscape; as the marble rolls, more and more alternate routes are bypassed until the marble becomes confined to one groove out of all the other possible channels.

That genetics has evolved as it has with the decisive rejection of epigenetics is as much a historical accident and the product of internal and external politics as it is the result of neutral scientific processes.  Recognition of this contingent nature of the development of genetics actually constitutes an important aspect of the analysis of the narratives of epigenetics, and will be discussed in much more depth in the subsequent posts on the narratives of epigenetics.

That the discourse of genetics has evolved as it has over the last seventy years with the exclusion of epigenetic phenomena means that the introduction of epigenetics at this point in time now constitutes a significant challenge to the entire theoretical edifice of modern evolutionary thought.  If epigenetics as promoted by Waddington and others had been accepted into the mainstream of genetics at a relatively early stage of its development, epigenetics likely would have been incorporated into the overall theoretical structure of genetics without too much disruption.  However, that genetics has evolved within its specific trajectory – as an example of “canalization,” which is another of Waddington’s important conceptual contributions to evolutionary theory[2] – has committed mainstream genetics and geneticists to a whole nest of theories and assumptions and empirical results to which the newly reemerging science of epigenetics now represents such fundamental challenges.

Some of the philosophical roots of the dogmatic limitations of the Modern Synthesis and the implications of the challenges to its basic ontological commitments introduced by epigenetics were discussed by Waddington sixty years ago.  In particular, the insuperable wall between genes and their environment constructed by the modern science of genetics—and codified within modern evolutionary thought as “the central dogma of molecular biology”[3]—is for Waddington evidence again of the “exaggerated atomism” which is the “gravest defect” not just of modern genetics but of modern science as a whole.[4]  This dichotomization of organism and environment commits modern evolutionary theorists and geneticists to the idea that, in Waddington’s words:

All living things, man included, had been brought into being by the collocation of two entirely independent factors: on the one hand the occurrence of mutations whose nature was totally unconnected with any ambient circumstances, and on the other hand a sieving process in which the environment merely selected from organisms which were offered to it ready made as units of being…each [factor] having its character in its own right, which come together with as little essential inter-relation as a sieve and a shovelful of pebbles thrown on to it.[5]

The philosopher Alfred Whitehead locates the pervasiveness of this “facile vice of bifurcation” as the inevitable result of the commonsense – but incorrect – perception of objects as ‘out there’ and as obviously distinct from the entity ‘in here’ that is perceiving those objects.[8] This dichotomization of environment and organism which is so fundamental to modern genetics and the Modern Synthesis constitutes a breach “as complete as the Cartesian dualism of mind and matter,”[6] for which Waddington proposes epigenetics as a means of “healing” this unwarranted and ultimately unscientific separation of ourselves from our environments.[7]

That Waddington equates this fundamental ontology of genetics with Cartesian dualism is not an inconsequential scientific factoid.  Some form of substance dualism – e.g., mind over matter or the soul over the body – has been the implicit assumption of most philosophies and sciences and religions throughout the history of the Western world.  The Cartesian dualism of mind as substantially distinct from the matter it observes is the ontological and epistemological basis of modern science – primarily as the subject-object distinction.

The problem with such exaggerated and oversimplified internal/external or mind/matter dualisms is that they do not usually have a ready-made solution. In this case, at least, the exaggerated dualism is the alleged isolation of genes from their environments, which is remedied by the recognition of epigenetics as the intermediate level between genes and the environment.  Because in the end “organism and environment are not two separate things,” Waddington optimistically proposes his integrative and more interactive theory of evolution as a means of “healing” this unwarranted and ultimately unscientific separation of ourselves from our environments.[9]  Likewise, unraveling and challenging this fundamental dichotomization is also actually the primary way that epigenetics makes its impact on public policy.

I am curious to hear what you think. Leave your comments below and I will respond.

Also, if you find these thoughts I’ve shared interesting and worthwhile, Like this post, Reblog it, or Tweet about it using the buttons below.

 

[1] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin, 189.

[2] Waddington, C. H. (1942). Canalization of Development and the Inheritance of Acquired Characters. Nature 150 (3811), 563-565.

[3] Crick, F. “Central Dogma of Molecular Biology.” Nature 227 (1970): 561-563.

[4] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin, 188.

[5] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin, 189.

[6] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin, ix.

[7] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin,189.

[8] Whitehead, Alfred North. [1920] 1964. The concept of nature. Cambridge: Cambridge University Press,188.

[9] Waddington C.H. (1953). The strategy of the genes. London: George Allen & Unwin,189.

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2 thoughts on “The Epigenetic Evolution of Genetics (and Epigenetics)

  1. […] As discussed here, the father of modern epigenetics C.H. Waddington also highlights this dichotomization of organism and environment as evidence again of the “exaggerated atomism” which is the “gravest defect” not just of modern genetics but of modern science as a whole. Because in the end “organism and environment are not two separate things,” Waddington optimistically proposes epigenetics as a means of “healing” this unwarranted and ultimately unscientific separation of ourselves from our environments.[7] […]

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