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To: frgoff; BMCDA
[For pete's sake, that was debunked over half a century ago. And it hasn't been taught since then either.]

True enough. How long will it take for the fabricated Peppered Moth experiments to get expunged?

Just a soon as the creationists finally manage to demonstrate that it was actually "fabricated", instead of just telling lies saying it was. Aren't you guys tired of getting caught lying about science so often?

Any questions?

Gosh, that's just a little (*cough*) different from what you would have us believe based on their highly selective "choice" of creationist "experts", isn't it?

Why did you "forget" to mention the more comprehensive studies which have validated the original peppered moth research?

Regrettably, many creationists "have once more been indoctrinated with a ‘[dis]proof’ of evolution which is riddled with error, fraud and half-truths".

I will now include some excerpts from's excellent page on problems with Well's book "Icons of Evolution", which includes a lenghty treatment of his chapter about the Peppered Moth, much of which is relevant here (since creationists tend to naively repeat each other on this topic instead of ever looking to the primary literature itself).

So many things are wrong with Wells' 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 M.E.N. Majerus' 1998 book Industrial 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.


Peppered moth photographs, staged and otherwise. Wells raises a fantastic stink about the fact that the photographs of peppered moths in textbooks, showing light-colored typicals next to dark-colored melanics on differing backgrounds, are staged. But the point of such photos is not to prove the truth of the 'classic' story, it is to illustrate the relative crypsis of moth morphs on different backgrounds. Those who feel that their innocent faith in insect photography has been betrayed should consider the fact that most photos of insects in textbooks are probably staged; insects are, after all, small and difficult to photograph. The facts that peppered moths are sparsely distributed and, well, camouflaged also make them difficult to photograph.

But as it turns out, the differences between staged and unstaged photos are minimal. Readers who wish to see unstaged photos of peppered moths are advised to look up Majerus' Industrial Melanism. Majerus says that all of the peppered moth photos taken by him in the book are unstaged. Readers should consult the figures which are listed below. It may be possible to get permission to include the photos, but until then descriptions shall have to suffice.

(See the above link for the lengthy descriptions of the figures. But the point is that even the "posed" photos are hardly misrepresentations of wild settings.)

Even so, there are several photos that show peppered moths, on tree trunks, on more-or-less matching backgrounds. And guess what? These photos look no different than 'staged' photos of moths on tree-trunks. The most 'staged' aspect about a 'staged' photo is that two differing moth forms are shown side-by-side, but Majerus' first two photos from Plate 3 indicate that even this is not impossible. So the entire photo issue is a mountain made of a molehill.

It should also be noted that several (four) of these unstaged photos have some (minor but noticeable) degree of blurring (e.g., part of the moth will be out of focus). Insects in the wild do annoying things like move and fly away, and are often encountered in poor-light conditions, resulting in less-than-perfect photos. As scientific documentation of observations this is unimportant, but flawed photographs are exactly the kind of thing that are avoided in textbooks, and this is precisely why staging insect photos is a common practice for textbooks (as well as things like nature shows).

American peppered moth researcher Bruce Grant has many complaints about Wells' (and similar creationists') misrepresentations of the Peppered Moth case:
Wells' Chapter 7 is pretty similar to his earlier ms. "Second thoughts about peppered moths" that he posted on the web, and published in abridged form in The Scientist. I sent you my comments about that version about two weeks ago. My general reaction to this latest version is about the same. He distorts the picture, but unfortunately he is probably pretty convincing to people who really don't know the primary literature in this field. He uses two tactics. One is the selective omission of relevant work. The other is to scramble together separate points so doubts about one carry over to the other. Basically, he is dishonest.

He immediately launches the claim "that peppered moths in the wild don't even rest on tree trunks" (p. 138). This is just plain wrong! Of course they rest on tree trunks, but it's not their exclusive resting site. He quotes Cyril Clarke's lack of success in finding the moths in natural settings, but he omits mentioning Majerus' data which reports just where on trees (exposed trunks, unexposed trunks, trunk/branch joints, branches) Majerus has found moths over his 34 years of looking for them.


It is true that the photos showing the moths on trunks are posed (just like practically all wildlife pictures of insects are) but they are not fakes. No one who reads Kettlewell's paper in which the original photos appeared would get the impression from the text that these were anything but posed pictures. He was attempting to compare the differences in conspicuousness of the pale and dark moths on different backgrounds. Nobody thought he encountered those moths like that in the wild. At their normal densities, you'd be hard pressed ever to find two together unless they were copulating. I have always made a point of stating in photo captions that the moths are posed, and I think textbook writers have been careless about this. But they are not frauds.


On page 151 Wells claims Kettlewell's evidence has been impeached. This is nonsense. It has not. But I have argued, that even if it were entirely thrown out, the evidence for natural selection comes from the changes in the percentages of pale and melanic moths. It is this record of change in allele frequency over time that is unimpeachable. It is a massive record by any standard. (I can send a jpg file with graphs, if you'd like.) I have pointed out, and he quotes me, that no force known to science can account for these changes except for natural selection. Yet, he scrambles the ingredients here. He claims (top of p. 153) " is clear that the compelling evidence for natural selection that biologists once thought they had in peppered moths no longer exists." Of course the evidence for natural selection exists! That evidence is overwhelming. Wells, by attempting to discredit Ketttlewell's experiments about predation (and clearly there are things wrong with Kettlewell's experiments) doesn't stop at saying we can't be altogether sure about bird predation because of problems with Kettlewell's experiments. No. He says, instead, that the evidence for natural selection no longer exists. This is just plain wrong. He cannot support this sweeping statement, but he spins it into his conclusion by building a case against Kettlewell. This is what I mean about his tactic of scrambling arguments. He wields non sequiturs relentlessly.

Peppered Moth researcher M.E.N. Majerus likewise finds great fault with the standard creationist claims about the Peppered Moth:
Evidence of selective predation in the peppered moth is not lacking. It is just not provided in the quick text book descriptions of the peppered moth. How can it be. I have read some 500 papers on melanism in the Lepidoptera. In total, these papers probably amount to about 8000 pages, and the story is condensed into a few paragraphs in most textbooks for schools. Even in my own book, I could only give a review of the case covering about 60 pages including illustrations.


End-note: It is difficult to have an informed discussion of a complicated ecological system with those who have little or no experience of the system. My advice to anyone who wishes to obtain a fully objective view of this case is to a) read the primary papers that I based my review upon, and any other relevant papers, and b) gain some experience of this moth and its habits in the wild. Of all the people I know, including both amateur and professional entomologists who have experience of this moth, I know of none who doubts that differential bird predation is of primary importance in the spread and decline of melanism in the peppered moth.

In a review of a book about the Peppered Moth, researcher Bruce S. Grant states even more clearly the scientific validity of the Peppered Moth example:
Mark Twain once quipped that reports of his death had been exaggerated. Recent reports exaggerate the death of industrial melanism as an exemplar of natural selection.


Population geneticists define evolution as a change in allele (gene) frequency. Adult peppered moths come in a range of shades from mottled gray (pale) to jet black (melanic). We know from extensive genetic analysis that these phenotypes result from combinations of multiple alleles at a single locus. Changes in the percentages of the phenotypes in wild populations are well documented. The changes continue and are observable even now. The steady trajectory and speed of changes in allele frequencies indicate that this evolution results primarily from natural selection. J. B. S. Haldane's original calculation of a selection coefficient was estimated from the number of generations it took for the melanic phenotype to effectively replace the pale phenotype during the 19th century. More detailed records document recent changes. For example, near Liverpool, England, the melanic phenotype declined from 93 to 18% in 37 generations (one generation per year); this change is consistent with a 15% selective disadvantage to genotypes with the dominant (melanic) allele.


Fortunately, science assesses the correctness of work by testing its repeatability. Kettlewell's conclusions have been considered in eight separate field studies, of various designs, performed between 1966 and 1987. Some of the design changes--such as reducing the density of moths, randomly assigning moths to trees, altering locations on trees where moths were positioned, and positioning killed moths to control for differences in viability and dispersal--were made to correct deficiencies identified in his original experiments. L. M. Cook's regression analysis of fitness estimates from these experiments plotted against phenotype frequencies at their various locations shows the studies to be remarkably consistent (1).

Other mechanisms of selection have been proposed. An inherent physiological advantage of melanic over pale phenotypes is consistent with the rise and spread of melanism, but the widespread decline in melanism that followed the Clean Air Acts obviates that interpretation. Although the possibility remains that physiological differences might be facultative (changing with conditions), so far no experimental work supports this idea. To date, only selective predation by birds is backed by experiment.


The history of melanism in American peppered moths--which are conspecific with Kettlewell's moths, not a separate species as Hooper indicates--closely parallels what has occurred in Britain, and melanism is correlated in like manner with levels of atmospheric pollution (2). The American studies corroborate rather than contradict the classical explanation.

The case for natural selection in the evolution of melanism in peppered moths is actually much stronger today than it was during Kettlewell's time.

As is unfortunately common, a creationist attack on a scientific position (because it provides support for evolution) is yet again found to be biased, misleadingly selective, conflates minority scientific disagreements into images of total refutation, totally fails to acknowledge findings which undercut its argument, selectively quotes authorities in ways that the authorities themselves take strong issue with, and in general tears down scrawny straw-man misrepresentations which give grossly misleading impressions about the great volume of study and evidence behind the item the creationists are attempting to hand-wave away.

I've said it before and I'll say it again -- if you're getting your "scientific" knowledge from creationist sources, then odds are you really have no true idea what science is really about, or how much evidence there is for/against something.

More discussions of the science behind the Peppered Moth research, and why the creationist version (and creationist accusations of "fraud") are a great example of fraud and misrepresentation *by* creationists, not by scientists:

The story of the peppered moth


Moonshine: Why the Peppered Moth Remains an Icon of Evolution

LETTER: Charges of fraud misleading

I invite readers to learn the full story, and then compare it against the gross misrepresentations and omissions of creationist "frgoff"'s version in this thread...

Trying to "learn" about science from anti-evolution creationists is like trying to "learn" about conservatism from Michael Moore and Cindy Sheehan -- and for exactly the same reasons.

There's nothing wrong with the peppered moth example, and I'm getting tired creationists blatantly lying about it. And remember these are the kinds of blatant lies they want taught in schools in the interests of "equal time" and "teaching both sides". Yeah, that's "both sides" all right -- the truthful side and the dishonest side.

438 posted on 01/31/2006 6:20:09 PM PST by Ichneumon
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To: Ichneumon
Just added to The List-O-Links:

NEW Ichneumon's Discussion of Peppered Moths. FreeRepublic post (#438).

463 posted on 01/31/2006 7:23:25 PM PST by PatrickHenry (Virtual Ignore for trolls, lunatics, dotards, scolds, & incurable ignoramuses.)
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