Sunday, August 16, 2015

Jerry Coyne Demonstrates the Real Power of Selection

Jerry looking very evolved.
Just a quick post here, since it is too easy to dig deeply into these silly exercises of Coynage, but Jerry Coyne wrote a blog post in response to an email from Paul Nelson discussing the limits of natural selection as the explanatory show pony of the evolutionary circus, citing the work of various biologists.

Coyne frames this a "McLuhan moment" (Annie Hall reference) since he is such a big mucky-muck in the speculative science of squishy things that, unlike the Woody Allen character, he can in real life pull these great biologists "from behind the sign" and have them comment on whether Nelson understands their fine work.

But first, the relevant claim by Paul Nelson:
So when you [Jerry Coyne] tell your WEIT audience that natural selection is the only game in town for building complex adaptations, . . .  Readers who already know about the thinking of workers such as Eric Davidson, Michael Lynch, Andreas Wagner, John Gerhart & Marc Kirschner, or Scott Gilbert (all of whom, among many others, have recently expressed frank doubts about selection) must discount what you say about the centrality of natural selection to evolutionary theory . . .
To sum up, even though Coyne hollers loud and long that natural selection is the central, driving, omnipotent core of evolution, various noted biologists have "frank doubts" about the centrality of natural selection and/or unrestricted appeals to its creative power--specifically relevant to the alleged claim of Coyne (which he appears not to deny) that selection is by-and-large omnipotent and all-sufficient even if there are other evolutionary processes interfering along the way.  This counter-claim by Nelson is what Coyne will supposedly debunk.

Coyne then emails these biologists, signaling quickly that this is ultimately about whether their answers could be taken in support of an ID proponent and "creationist," and asks them (in an almost McCarthyist manner) whether any of them have "denied the efficacy of selection in accounting for adaptations" (a phrasing with a distinctly credal ring).  Actually, as generally as it's stated, I don't think a baraminologist would necessarily deny this.  I am tempted instead to say that these notables understood that Coyne was asking whether they thought any sort of macroevolution was achievable under the power of natural selection (which wouldn't surprise me), but Coyne actually lowered the bar by asking them whether they believe selection can account for the low-hanging fruit of "obvious adaptations."

Eric Davidson quickly agrees (included in Coyne's post) that Selection is important for "species-specific characters of all kinds," and then joins the two-minute hate for anything guilty of looking like creationism.  Andreas Wagner cuts to the very heart of Coyne's plea, and affirms that though they may disagree on so much, they're all committed materialists come-what-may, and Selection will always have a seat at the table.  John Gerhart consoles Coyne that selection is important, and they never tried to "belittle" Selection but only to better understand the poor, dear thing.

I have no idea whether Marc Kirschner has argued about about the significance of phenotypes as forcefully as Rudy Rucker has.  If so, I wouldn't be surprised, though I don't doubt for a second that Rudy Rucker kisses the ring of materialism as well. At any rate, Kirschner affirms his antipathy for "strange supernatural forces at work" and clarifies that his "point of departure from population biologists is to try add to our present knowledge. . ."  Is merely adding something new usually called a "point of departure"? I can't tell from what he says exactly which claims he's departing from or arriving at.  But I can tell that he has learned to love Big Evo, thanks to Miniluv.  

Larry Moran (yes, "SandwalkLarry Moran) thinks that Paul Nelson did not mischaracterize the views of these authors:
I think this [Nelson's assessment of the biologists] is basically correct. All of these authors question in some way or another the “centrality” of natural selection to evolutionary theory. We can quibble about the exact meaning of words and sentences but I, for one, don’t think Nelson is way off base here. ...  I don’t think Jerry’s question is fair. Paul Nelson was not accusing these authors of denying a role for natural selection in “obvious adaptations.”
Of all these authors, I find Michael Lynch's response is interesting.  He describes non-adaptive causes as steering natural selection, which softens his erstwhile characterization of them as constraining selection (the difference being rhetorical rather than substantive).  Paul Nelson elsewhere quotes Lynch explaining that non-adaptive causes/factors
dictate what natural selection can and cannot do. Although this basic principle has been known for some time, it is quite remarkable that most biologists continue to interpret nearly every aspect of biodiversity as an outcome of adaptive processes. This blind acceptance of natural selection as the only force relevant to evolution has led to a lot of sloppy thinking, and is probably the main reason why evolution is viewed as a soft science by much of society. ([The Origins of Genome Architecture] 2007a, p. xiii).  [emphases mine]
(Oh, that's one good reason, Mr. Lynch!)  Other specific references to Lynch's work available herehereherehere, and here.  Gee, Michael Lynch almost sounds like a ... secular creationist!  Don't worry, though.  He'll stammer his way back to Darwin if he sees the heretic fires burning.  Shape him up right smart, boss!  Got his mind right!  But it does seem that he disagrees with Coyne in precisely the way that Nelson framed it (rather than Coyne's re-framing).
Anyway, Coyne has demonstrated here the real power of Natural Selection.  It has great power as a rallying force for true believers in the power of the evolutionary narrative and to instill fear in maverick biologists whose work might "give a piece of candy to" ... really, anyone who dares to think that biology shows potential evidence of design. To question selection too openly is to invite the public to consider whether answers that were asserted with great authority were all that certain.  And these intrepid materialists won't be mistaken for selection deniers.

Think about that before you say something that might be taken to belittle poor, noble Selection, who, though unable perhaps to explain the diversity and complexity of life, can nonetheless take credit for propping up methodological naturalism with its charismatic powers of plausible speculation, an even more worthy feat.
- David Berlinski, The Devil's Delusion, p. 197
We agree that very few potential offspring ever survive to reproduce and that populations do change through time, and that therefore natural selection is of critical importance to the evolutionary process. But this Darwinian claim to explain all of evolution is a popular half-truth whose lack of explicative power is compensated for only by the religious ferocity of its rhetoric. . . . Mutations, in summary, tend to induce sickness, death, or deficiencies. No evidence in the vast literature of heredity changes shows unambiguous evidence that random mutation itself, even with geographical isolation of populations, leads to speciation.  Lynn Margulis, Dorion Sagan, Acquiring Genomes (Basic Books, 2003) p. 29
Postscript:  To continue on the "sloppy thinking" motif of Lynch's, it is worthwhile to reflect on how easy it is for biologists to equivocate in their own heads about whether they are talking about microevolution, macroevolution, selection, common descent, population genetics...  They start to all blend together into a big sloppy thought-smoothie.  Especially in the presence of a denier who has doubleplus ungood anti-science thoughtcrimes, at which point these concepts not only meld together but congeal into an impenetrable meatball.

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