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To: Ichneumon
not mistakes or corner-cutting which was later corrected. So that leaves out "Nebraska Man" or Haekel's embryos

8-) And the peppered moth fiasco was "corner cutting" too?

531 posted on 01/30/2005 6:51:36 AM PST by Aquinasfan (Isaiah 22:22, Rev 3:7, Mat 16:19)
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To: Aquinasfan
8-) And the peppered moth fiasco was "corner cutting" too?

CONGRATULATIONS!

Remember just a few minutes ago when I warned you thusly?

Friendly warning: If you've made the mistake of reading Wells "Icons of Evolution" anti-evolution book -- and *believing* it -- you need to read these before you attempt to respond: Icons of Evolution FAQs . They document just how wildly off-base (and how much of a *documented FRAUD*) Wells himself is in his bizarre accusations. Don't say I didn't warn you.

Well, you chose to ignore my advice, and so you've just made a fool of yourself, because there's NOTHING WRONG with the peppered moth example, and the link I gave you explains at length why Wells has his head up his butt when he claims there is. Here's what you neglected to read before you shot your mouth off (DESPITE my clear warning to you and link to the information):

Chapter 7: Peppered Moths

So many things are wrong with Wells's treatment of peppered moths (Biston betularia) that it is hard to list them all; but I will try. The authoritative reference on this topic is Michael Majerus' 1998 book Melanism: Evolution in Action. This book includes two long chapters on Biston. The first chapter, "The peppered moth story," recounts the basic story of melanism in Biston, and relates how this story was pieced together by Kettlewell and others. The second chapter, "The peppered moth story dissected," gives a thorough critical review of the basic story, considering aspects and details of the basic story in the light of research (by Majerus and others) post-dating Kettlewell.

Crucially, however, Majerus clearly and explicitly concludes that, in his view, Kettlewell got things basically correct. At the beginning of his second peppered moth chapter, Majerus writes,

First, it is important to emphasize that, in my view, the huge wealth of additional data obtained since Kettlewell's initial predation papers (Kettlewell 1955a, 1956) does not undermine the basic qualitative deductions from that work. Differential bird predation of the typica and carbonaria forms, in habitats affected by industrial pollution to different degrees, is the primary influence of the evolution of melanism in the peppered moth (Majerus, 1998, p. 116).

Majerus is so clear on this point that one suspects that he was anticipating that his critique would be misinterpreted by non-peppered moth researchers. It seems that there is a "too good to be true" quality about the peppered moth story that leads people to interpret any hint of criticism as a sign that the whole basic story is crashing down. Scientists are by no means immune to this tendency, and indeed they may be more prone to it given the regularity with which popular ideas have been overturned throughout the history of science. The press has an even greater tendency towards snap judgements and oversimplifications when it comes to scientific discussions. Antievolutionists, on the other hand, have always been stuck muttering "it's just microevolution within a species." While this is true, the rapidity and obvious adaptiveness of the change effected by natural selection still seemed to give antievolutionists discomfort. Therefore, it is understandable that when Wells and his fans sniffed a scientific controversy over peppered moths (in truth it was a fairly marginal kind of controversy), they blew things way out of proportion.

Summary of Wells's treatment of moth resting places. To review, Wells's primary objection to the peppered moth story was this:

Most introductory textbooks now illustrate this classical story of natural selection with photographs of the two varieties of peppered moth resting on light- and dark-colored tree trunks. (Figure 7-1) What the textbooks don't explain, however, is that biologists have known since the 1980's that the classical story has some serious flaws. The most serious is that peppered moths in the wild don't even rest on tree trunks. The textbook photographs, it turns out, have been staged. (Icons, p. 138)

[Figure 7-1 is on Icons, p. 139; these are drawings by Icons illustrator Jody F. Sjogren; the source photo, if there is one, is not cited. Confusingly, the caption for the figure is not on page 139 but overleaf on page 140. These are not encouraging signs in a book purporting to critique textbooks.]

The discussion thus far has shown that Wells's "most serious objection" to the peppered moth story is completely baseless: first, peppered moths do in fact rest on tree trunks (a significant portion of the time although not the majority of the time, according to Majerus' data). Second, textbook photos are used to show relative crypsis of moth morphs, not to prove that peppered moths always rest in one section of the trees. And third, Majerus himself has taken unstaged photos of peppered moths on matching tree trunk backgrounds, and these are not significantly different than staged photos; this eviscerates whatever vestige of a point Wells thinks that he has.

The scientific literature. Having dealt with Wells's "most serious objection," let us turn to Wells's use of the scientific literature. The primary problem is that Wells gives inordinate weight to a few scattered review papers, by biologists who are not major peppered moth researchers [4], that question the standard view (that bird predation on different colored moths on differently polluted backgrounds caused the darkening of moth populations as pollution increased, and that as pollution decreased this process worked in the opposite direction). Their criticisms have been answered by peppered moth researchers (Grant, 1999; Cook, 2000; Grant and Clarke, 2000; Majerus, 2000). And, as pointed out in the introduction, since Wells bases his argument on the idea that the experts are disowning the 'icons' in their respective fields, Wells is falsified if those experts contradict him.



532 posted on 01/30/2005 7:05:06 AM PST by Ichneumon
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