Monday, November 19, 2012
Michael Behe in Toronto: Part 2
The gist of Behe's talk was that "Darwinism" can't explain macroevolution. The problem isn't common descent—Behe agrees that common descent is "trivial." The problem isn't natural selection—Behe doesn't have a problem with natural selection. The problem is random mutation. It's incapable of generating the required changes in a timely manner.
Behe pointed to the problems of getting off of a local adaptive peak in order to climb a higher nearby peak. He pointed out that in order to move down a peak you would have to become less adaptive (i.e. maladaptive). He did not mention that fixation of slightly deleterious mutations is part of modern evolutionary theory because he only talks about Darwinism.
Behe claims that the probability of fixing multiple mutations is so low that most populations could never do it in billions of years. The implication—obvious to all—is that you need divine intervention in order to get the job done.
Behe claims that none of the evolution experiments have demonstrated the evolution of new functions. They all, according to Behe, involve disabling or modifying existing genes, a simple pathway that's quite compatible with the limitations of Darwinism.
He talked about Richard Lenski's long term E. coli experiment, pointing out that evolution of the ability to use citrate turned out to be as simple as activating a transporter gene that was otherwise silent. The experiment has followed more than 55,000 generations; that's equivalent to more than one million years of mammalian evolution and still nothing spectacular has happened.
After the talk I spoke with a Yong Earth Creationist who was very impressed by this result. He asked me why Lenski didn't see fruit flies forming in his flask since one million years is a very long time. The result shows that evolution fails the experimental test.
The audience was very polite. There were a few questions challenging Behe but they focused on rather obscure points that were way over the heads of the audience and, besides, Behe gave reasonable answers. The dominant impression was that Behe gave a very technical talk in a prestigious venue and none of the scientists in the audience could refute what he was saying. The fact that few people could understand what he was saying was irrelevant. It all sounded very scientific.
As one of the Sandwalk readers noted, the religious high school students who were bussed in would have rightly concluded that what Behe was saying is mainstream science sanctioned by the University of Toronto and the Faculty of Medicine. It's very difficult to refute Behe's claims in such a venue. You can't just stand up in question period and tell the audience that Behe is full of crap and that he's lying about evolution. (Although I was sorely tempted to do just that.)