Re-reading Provine (1971), part 1

William Provine‘s seminal work of history, The Origins of Theoretical Population Genetics (1971), recounts how the foundations of modern neo-Darwinism were established in the first 2 decades of the 20th century.  Superficially, Provine’s book aligns with the standard triumphalist narrative in which the architects of the Modern Synthesis combine selection and genetics to yield a workable theory that refutes the mutation-driven view of early geneticists.

However, it also has another story to tell.  If we read the book with a critical eye, we’ll find a completely different story that expains why Provine himself, in a 2001 reprinting, said that the synthesis “came unraveled” for him in the period after 1980.

Understanding the history of our field is fraught with difficulty, largely because of what evo-devo-ist Stuart Newman referred to as an “unremitting 90-year campaign to identify ‘evolutionary theory’ with ‘Darwinism’“.   Newman, who was trained as a physicist and thus was never fully indoctrinated, finds it odd that the intellectual history of evolutionary biology, unlike the history of physics, has villains.  Our history has characters like Bateson and de Vries whose role in the story is to be spectacularly wrong— and yet somehow influential, leading gullible scientists on a stampede of error until truth and sanity are restored by Darwin’s deputies.   Among historians and philosophers, the self-serving version of history peddled by Ernst Mayr and his followers has gained such notoriety that it has a special name: “Synthesis Historiography”, i.e., telling history in a way that makes things turn out right for the Modern Synthesis.  For instance, Mayr’s Essentialism Story, widely taught in textbooks, is taken down by Mary Winsor (2006), who literally calls it a “fiction” “fabricated” by Mayr.

When I first examined Provine’s book, I dismissed him as part of the cohort of historians and philosophers who were drinking Mayr’s kool-aid and churning out crap starting in the 1970s and 1980s.  Indeed, Provine’s narrative has the same official cast of good guys and bad guys, in their conventional roles: the good guys appreciate Darwin and understand the power of selection (Weismann, Pearson, Castle, Fisher), and the bad ones are confused and delay progress, rejecting selection in favor of macromutations, based on their misunderstandings (de Vries, Bateson, Johannsen, Morgan).  Darwin gets credit for everything, even ideas he rejected, because he inspired others to expose his errors.

For that reason, I did not bother to read OTPG closely— until I had the ambition to publish a historical piece on evolutionary views of the early geneticists, covering exactly the same period (1900 to 1920), with a thesis directly contradicting the standard narrative.  One can’t claim to be a scholar, utterly contradict the seminal work on a topic, and refuse to explore the reasons for the difference!

So, I had to go back to Provine’s book to see how a respected historian who clearly studied the primary sources could have failed to notice that the “mutationist” villains of Synthesis Historiography laid the conceptual foundations of evolutionary genetics, and developed a synthetic view (combining mutation, selection and inheritance) that has held up better than the views of the Synthesis architects.

And what I found, unexpectedly, is that Provine’s analysis provides considerable support for this revisionist view.  When my co-author and I finally published our analysis, we cited Provine heavily (see Stoltzfus and Cable, 2014).

I had underestimated Provine.  To be sure, the facts in OTPG are embedded in a conventional narrative, but Provine was too much of a scholar to leave out key facts and quotations, even when they don’t fit the narrative.  Furthermore, Provine penetrates the fog surrounding the Modern Synthesis in a way that few historians or scientists have done.  The central claim of the Modern Synthesis is that genetics, when understood properly at the population level, justifies Darwin’s view of evolution by natural selection, and eliminates all rivals, the key rival theory being the “mutationist” or “Mendelian” view of the early geneticists.   Provine slowly lays out the logical foundation of this claim, which comes to rest on a very specific argument— based on results from experimental and theoretical population genetics— regarding the power of selection to create new types without mutation.  Provine calls this power “the effectiveness of selection” or “the efficacy of Darwinian selection,” and suggests that once this was established around 1920, the revival of Darwinism could proceed on a rigorous genetical basis.

IMHO, once one understands what “the effectiveness of selection” means, and recognizes the role of this claim in evolutionary rhetoric, the Modern Synthesis will come unraveled, as it did for Provine.  In the next few blogs, I will attempt this unraveling in 3 steps, each based on a quotation from Provine that contradicts the standard SH narrative, and reveals his understanding of the evolutionary views of Darwin, Pearson, Bateson, Morgan, and Fisher, et al:

  1. On p. 43, Provine quotes Bateson referring to “the subsequent perfection of the form . . .  by a slow process of selection”  and stating that “when the unit of segregation is small, something mistakeably like continuous evolution must surely exist.”   Wait!  Bateson is a mutationist and a saltationist!  Weren’t we told that Bateson rejected smooth change (and selection)?   If Bateson allows smooth change, why isn’t he a Darwinian?  How does Provine distinguish him from Fisher?
  2. On p. 139, Provine describes the first (reasonably full) model of allelic selection as “the perfect complement to Morgan’s theory of evolution by single gene replacement”.  Wait!  Morgan is the enemy, on the wrong side of Darwinism. Didn’t Morgan reject selection?  Provine says allelic selection is “the perfect complement” to Morgan’s theory, but his larger theme is that “Mendel’s theory of heredity was the perfect complement to Darwin’s idea of natural selection”.  What distinction is Provine trying to make?
  3. On p. 143, Provine is explaining why Pearson refused to consider (for his journal Biometrika) a draft of Fisher’s famous 1918 paper: “Pearson claimed, and Darwin would probably have agreed, that the continuous variations in a pure line were heritable and that continued selection in a pure line should be effective. . .  Fisher, unlike Pearson, believed in Mendelian inheritance and the continuity of the germ plasm.”  Wait!   What does Provine mean by suggesting that Darwin and Pearson believed in the inheritance of environmental variations?  How can Mendelism be the “perfect complement” to Darwin’s theory if Darwin himself rejected it?

Each of these quotations reveals a hole in the standard SH narrative.  Provine believes that Norton’s 1915 model of allelic selection is the perfect complement to Morgan’s theory, but not to Darwin’s.  I’ll explain how such a distinction is possible.  Bateson understood the potential for smooth selection-driven change, and articulated this idea when little Ronny Fisher was a schoolboy.  The difference, usually covered up by the fog, is that a saltationist like Bateson also allows evolution by discrete steps or jumps, while a Darwinian like Fisher believes that smooth change can explain everything.   Pearson and Darwin really did have a non-Mendelian view, and allegiance to that antique view is the achilles heel of the Modern Synthesis, a point that will become clear by unwrapping what “the effectiveness of selection” really means.


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