The Intelligent Design (ID) crowd is jubilant over the publication of a paper by a trio of ID authors (Ola Hössjer, Günter Bechly, and Ann Gauger) in a sub-prime but legitimate journal. This paper is an example of a common straw man argument employed by ID. In the straw man approach, you set forth some weak or flawed “straw man” version of your opponent’s position, knock it down, and then proclaim victory.
The straw man in this case is a scenario where the evolution of a complex trait requires the prior accumulation (appearance and fixation) of a large, predefined set of nonbeneficial mutations before there is any functional, selectable benefit from these mutations. ID folks keep proposing that this scenario is the way evolution proceeds, and then they present detailed calculations showing how probabilistically disfavored this process would be.
These calculations serve to knock down their straw man, so the ID theorists can claim to their supporters that they have (once again) vanquished “Darwinism”: the “waiting time” for the accumulation of a large set of predefined mutations in this disjointed manner is much longer than geological time permits for evolution.
Unfortunately for their case, their straw man is a non-starter. Actual, practicing biologists have sound reasons to hold that this proposed genetic scenario is simply not how evolution proceeds in the real world. Biologists are not fooled or impressed by this waiting time argument, although the willing supporters of ID are.
I have summarized the key issues in very general terms. To put more meat on the bones of this discussion, I commend a short article, “Waiting time problem” and imaginary hurdles for evolution, by Mikkel Rasmussen in Panda’s Thumb. Rasmussen critiques the Hössjer, et al. paper more explicitly. He starts out with the devastating observation:
[Hössjer, et al.] argue that a complex adaptation would take a very long time to evolve given certain imaginary conditions. They never give any evidence that any known complex adaptation had to evolve through their imaginary scenario, so the relevance of their paper to real biology is only that, imaginary.
Rasmussen goes on to provide a link to an experimental study that confirms that (contrary to the ID straw man) you don’t necessarily have to accumulate a lot of random mutations in a section of DNA before any selectable advantage is obtained. Bonus: the long string of informed comments on Rasmussen’s article is an education in itself.