Last month we noted two news stories that signal major changes ahead for evolutionary theory — an upcoming conference by the Royal Society seeking a “revision of the standard theory of evolution,” and a $8.7 million research project underwritten by the Templeton Foundation offering, according to Science Magazine, an “evolution rethink” (“Intelligent Design Aside, from Templeton Foundation to the Royal Society, Darwinism Is Under Siege“).

Developments like that obviously stick in the craw of Darwin defenders. For years they have assured the public that the theory requires few or no emendations.

Think of it in domestic terms. You might make improvements around your house — replacing worn fixtures and appliances, say — or even add on a room or two, but it’s still the same house. Or is it? Deconstruct and rebuild enough and, lo and behold, before too long you’ve gone and built a completely different structure, sharing little with the old other than the piece of property it sits on.

What then do we mean when we speak of the heralded “Extended Evolutionary Synthesis”? Journalist Susan Mazur got hold of two leading articulators of the Extended Synthesis and asked them how extensive the revisions will be. It turns out there’s a fundamental disagreement on that.

One, Kevin Laland, an organizer of the Royal Society meeting, has in mind something improved but not entirely new. Mazur got this comment from him:

The extended evolutionary synthesis does not replace traditional thinking [he means neo-Darwinism], but rather can be deployed alongside it to stimulate research within evolutionary biology. The new perspective retains the fundaments of evolutionary theory — genes and natural selection remain central, for instance — but there are differences in how causation in biology is understood. [Emphasis added.]

The other, Gerd Müller, is clear that he is building a new house, not merely refurbishing the old. He told Ms. Mazur:

The term “Extended Synthesis” was never meant to refer to an “extension of” the Modern Synthesis but to a new and different kind of synthesis that includes many more components — hence “extended.” The inclusion of the new concepts completely alters the structure and “logic” of the evolutionary model, and hence (as a theory) can only replace the Modern Synthesis, not merely improve it. This is not a change in opinion. Denis (Noble) originally also thought that our term “extension” referred to an “add on,” but now we are in agreement that this is not the case.

He added, after consulting a thesaurus:

I wrote to let you know what the scientific meaning of “Extended Synthesis” is. Many terms in science have a different meaning from the public usage, because they depend on particular definitions of the phenomena to which they apply.

…

There is no dilemma. I quick check with your Word thesaurus will show you that synonyms of “extended” include “comprehensive”, “extensive”, “broad” etc. This is the meaning in our case. As in “Extended Family”, referring to the wider family and not to an extension of the family.

Laland and Müller are co-authors of a paper in Proceedings of the Royal Society B, “The extended evolutionary synthesis: its structure, assumptions and predictions.” They wrote there:

The conceptual framework of evolutionary biology emerged with the Modern Synthesis in the early twentieth century and has since expanded into a highly successful research program to explore the processes of diversification and adaptation. Nonetheless, the ability of that framework satisfactorily to accommodate the rapid advances in developmental biology, genomics and ecology has been questioned. We review some of these arguments, focusing on literatures (evo-devo, developmental plasticity, inclusive inheritance and niche construction) whose implications for evolution can be interpreted in two ways — one that preserves the internal structure of contemporary evolutionary theory and one that points towards an alternative conceptual framework. The latter, which we label the ‘extended evolutionary synthesis’ (EES), retains the fundaments of evolutionary theory, but differs in its emphasis on the role of constructive processes in development and evolution, and reciprocal portrayals of causation.

Heading into the November Royal Society meeting, we predict more haggling over the nature and extent of the renovation.

A lot rides on the question, including the reputations of some hardline Darwinists. It’s not merely a question of academic, or philosophic or theological, interest. There are issues of personal prestige here, and we know those trump all for many people, not excluding scientists. The hardliners are not going to go down without a fight.

Photo credit: Olaf Köhler (Own work (Jahn-Bergturnfest-Ausschuss)) [CC BY-SA 3.0 or GFDL], via Wikimedia Commons.