Just ran across an article entitled, “Between ‘‘design’’ and ‘‘bricolage’’: Genetic networks, levels of selection, and adaptive evolution” by Adam Wilkins. It was published the same year as Da Matrix in PNAS. What is so striking about the article is the vast amount of overlap between the views of Wilkins and yours truly. Let me begin by quoting a paragraph from his conclusion and then, over the next couple of days, I will provide some juicy excerpts.
This article has explored the ways that evolutionary trajectories are influenced by (i) the properties of gene products, (ii) the on/off switches that control transcription of individual genes, and (iii) the structured properties of the regulatory ensembles we know as genetic network modules. It would be overstating the case to call the biases created by these selection-honed properties ‘‘constraints,’’ which connotes strong barriers, but it seems certain that these properties must exert some preferential influence or channeling effects at the start of every evolutionary departure. Such molecular attributes make possible the kinds of ‘‘facilitated variation’’ described by Gerhart and Kirschner (56). Their perspective is both fully consistent with and complementary to the one sketched here.
If you have read the DM or read this blog regularly, that paragraph, written for a mainstream scientific journal, should give you a warm, fuzzy-eared feeling.