One of my postings, Good Science Writers: Richard Dawkins, has been re-posted on RichardDawkins.net. This doesn't happen very often—in fact this may be the very first time. I can't imagine why they would have selected this particular posting.
I mentioned that some of the Dawkins metaphors are misleading and I suggested that Climbing Mount Improbable was one example. That prompted a comment from Richard Dawkins so I replied on his website. In case anyone is interested, I'm reproducing it here.
Richard Dawkins asks,
I am interested in the suggestion that Climbing Mount Improbable might not be an ideal title.
Richard, we've been over this ground before but for the benefit of the lurkers let me explain why I think the metaphor is inappropriate.
To begin with, you use the Mt. Improbable image as a metaphor for evolution. This is misleading since evolution encompasses more than just adaptation. It would be difficult to apply the "Climbing Mt. Improbable" metaphor to the organization of our genome, for example, since it's clearly not well-designed and could never be characterized as the peak of an adaptive landscape.
But even as a metaphor for adaptation the image is less than perfect. Most readers will see the peak of Mt. Improbable as a goal of adaptation, implying that evolution somehow recognizes that there is an ultimate perfection that all organisms seek to achieve by reaching the summit. As you well know (I hope) there are very few (any?) species that are perfectly adapted to their environment. If this were true, adaptation would cease because the species resides on the summit of Mt. Improbable.
Thus, in the real world, species tend to move about in the foothills rather than attempt to scale the highest peak. As long as they are good enough to survive and reproduce that's all that's required.
Yes, some individuals within the population might acquire a mutation that makes them a little more fit but in most cases the selective advantage will be too small to make much of a difference. I don't believe there's any great pressure to get to the top of Mt. Improbable. That's why we usually don't see perfection in nature. And it explains why most organisms do not look as though they have been designed by some intelligent being. If anything the "design" looks more like a Rube Goldberg creation, and I doubt that anyone would say that those creations represent the peak of perfection.
I prefer a different view of evolution, one that emphasizes chance and accident [Evolution by Accident]. For me, the metaphor of "Climbing Mt. Improbable" is quite wrong as a metaphor of evolution.
Now, I understand that you disagree about the role of chance and accident. You say, for example, on page 326 of Climbing Mt. Improbable, "It is all the product of an unconscious Darwinian fine-tuning, whose intricate perfection we should not believe if it were not before our eyes" (referring to the evolution of figs and fig wasps). For someone who believes that such a description is characteristic of most evolution (adaptation) the "Climbing" metaphor may seem quite appropriate.
BTW, I agree with you that your case for adaptationism is much stronger in Climbing Mt. Improbable than in The Blind Watchmaker. I especially like the chapter you mention, The Museum of All Shells, where you discuss - among other things - the contrast between your view of evolution and the mutationist view. Ironically, you begin that discussion by pointing out that this is a sophisticated controversy, "... and Mount Improbable, even in its multiple-peaked version, isn't a powerful enough metaphor to explore it."
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