Nelson in the Lions' Den
There's an interesting dialogue going on now at Why Evolution Is True. In an email to Jerry Coyne, Discovery Institute's Paul Nelson cited the names of several evolutionary researches who in their writing expressed doubts on the sufficiency of the Darwinian mechanism of blind churning and natural selection to explain the forms of life and how they got there.
Jerry Coyne, the author of WEIT, emailed those same authors -- Eric Davidson, Michael Lynch, Andreas Wagner, John Gerhart, and Marc Kirschner -- asking if they agreed with Nelson's citing them. They wrote back that they do not, and Coyne made a blog post of this. But Nelson in the comments cites at length from the writing of these same researchers, where it's pretty evident that his initial point to Coyne is justified: doubts about natural selection, not about its existence obviously but on its sufficiency, are very much out there and in play in the field of biology.
At this a bunch of anonymous commenters leap on Dr. Nelson, with the usual accusations of quote-mining. Nelson calmly replies with further citations from the work of these authors, only to be greeted with more accusations of being a liar, stupid, etc. Finally, none other than biochemist Larry Moran, very far from being an admirer of intelligent design, weighs in to say that Nelson in his presentation of the disputed authors' views is right!
I think this 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. Perhaps Nelson shouldn't have said "expressed doubts about selection" because it could be taken to mean that the authors deny that positive natural selection exists. I don't think that's what Paul Nelson meant.And:
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."Look, you can never really know for certain what another person thinks and believes in his heart, his true motivations in saying or doing as he does. All you have is at what he says, the record of the words he selected, presumably to express his thoughts. That's all. The authors in question are not intelligent design advocates but in their previous writing they expressed strong doubts about ideas that are central to contemporary Darwinian thinking. When called on this by Coyne, and told they were being cited by an ID advocate, they assured Dr. Coyne of their fundamental evolutionary orthodoxy.
In short, they voted for doubt on natural selection before they voted against it.
Does this constitute a change of heart? Again, there's no way to know because we can't see into their hearts. We can only read their words and the words say what they say.
But I can try to imagine myself into a place like the one I think they may occupy. In the days of the Inquisition, Spanish Catholics with Jewish backgrounds often found themselves the objects of terrifying scrutiny. Someone reported that you had been observed to refuse pork or avoid work on Saturday. An inquisitor called you to account for yourself and you had to make a decision. Seemingly, the prudent thing was to immediately assure him there was some mistake. "Someone said that about me? Absurd! Here, hand me that ham sandwich. Delicious!"
In the present persecutory climate, given the way reputations are shredded by anonymous informants on the Internet and with "friend to creationists" being a label considered by many in university life as one step above "wife beater," I know that if I were someone with an academic career in evolutionary biology and I got an email like that from Coyne, I would be nervous. The prudent thing to do would be to assure him there is some mistake.
So the authors wrote what they wrote and that can't be undone. But really, much more important than the published statements that Paul Nelson cites are the arguments he brings to bear. I referred you earlier to his recent and superbly clear talk, whose gist he summarizes in the comments thread at WEIT:
Text from one of my Saddleback slides:Rather than tussling over what biologist said what, why not respond to Paul's argument? Set aside the extracts from published scientific works and the perhaps hastily composed emails responding to demands for confirmation of evolutionary orthodoxy. Tell us, on the merits, why Paul Nelson is wrong. Ah, but that, so far at least, Jerry Coyne will not do.
1. Animal body plans are built in each generation by a stepwise process, from the fertilized egg to the many cells of the adult. The earliest stages in this process determine what follows.
2. Thus, to change -- that is, to evolve -- any body plan, mutations expressed early in development must occur, be viable, and be stably transmitted to offspring.
3. But such early-acting mutations of global effect are those least likely to be tolerated by the embryo.
Losses of structures are the only exception to this otherwise universal generalization about animal development and evolution. Many species will tolerate phenotypic losses if their local (environmental) circumstances are favorable. Hence island or cave fauna often lose (for instance) wings or eyes.