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Author Topic:   Peppered Moths and Natural Selection
randman 
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Posts: 6367
Joined: 05-26-2005


Message 43 of 350 (261695)
11-20-2005 10:50 PM
Reply to: Message 41 by RAZD
11-20-2005 10:39 PM


Re: If it is natural selection, what is false about protraying it as natural selectio
If you read the OP you would see that of the moths found resting naturally the greatest number were found in the trunk\branch crotch.
While this is not an absolute number percentage, it does show that they do in fact rest in these locations naturally.
That fails to address the issue. If you are claiming resting on darker tree trunks is a significant factor, then there is a need to show how often they rest on tree trunks so we can assess whether the claim is valid. The fact they merely rest on tree trunks is not sufficient.Also, it is not clear that this analysis includes other places of rest, such as the ground.

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 46 of 350 (261710)
11-20-2005 11:13 PM
Reply to: Message 45 by RAZD
11-20-2005 11:12 PM


Re: If it is natural selection, what is false about protraying it as natural selectio
1. First off, no the study does not rule out all the various factors that could have influenced whether lightly colored or darkly colored moths became more dominant as a result of soot. It could be something else entirely, perhaps another aspect of pollution, coincidence, etc,...
Unless someone can show where all of the other potential factors have been ruled out, please don't respond until you (evos here) provide that.
2. Secondly, birds have the ability to see in the UV spectrum and the ignorance of that basic fact renders moot any conclusions about what birds actually see in this instance.
It appears one study indicates UV vision reverses things, but perhaps I am misreading that. If you want to get into this subtopic, I'll answer you in that regard.
3. Peppered moths are nocturnal and so releasing them in the day-time to draw conclusions about their behaviour also makes the study based on faulty data.
Please cite the studies that show statistics related to bird versus bat predation, day-light habits, etc....Releasing moths into the day-light where they are stunned by the change is not a valid approach.
4. In reality, birds are not even the primary predator of peppered moths, but rather bats are. Bats method of sensing prey is totally different, and relies on sound waves and thus bats tend to capture moths in flight rather than while they are resting. This fact further makes the claims of the study to be somewhat fantastic in nature and without solid scientific standing.
Please cite where bat predation factors are accounted for.

This message is a reply to:
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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 49 of 350 (261715)
11-20-2005 11:30 PM
Reply to: Message 47 by arachnophilia
11-20-2005 11:18 PM


Re: If it is natural selection, what is false about protraying it as natural selectio
Just list all the other potential factors that were considered, and how they were ruled out, or concede that attributing causality based on coorealation is faulty science. I particularly would like to see some analysis done on bat predation, considering bats are their primary predator, I believe.

This message is a reply to:
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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 52 of 350 (261722)
11-20-2005 11:45 PM
Reply to: Message 51 by RAZD
11-20-2005 11:42 PM


Re: my response, bad as it was the first time and worse for repetition.
Please list all the other potential factors and show why they are not considered causal.
Dismissing asking for this as ad hoc doesn't work. You have to show you considered all potential causes, and you have not.
Please do so.
Also, you claim studies exist but refuse to cite them. Please back up your claims. The fact is all the studies do not agree with the initial claims such as the studies cited below.
When biologists looked beyond Birmingham and Dorset, where Kettlewell had conducted his experiments, they found discrepancies between Kettlewell's theory and the actual geographical distribution of melanic moths. For example, if melanic moths in polluted woodlands enjoyed as much of a selective advantage as Kettlewell's experiments seemed to indicate, then they should have completely replaced typicals in heavily polluted areas such as Manchester (Bishop and Cook 1980, Mani 1990). This never happened, however, indicating that factors other than selective predation must be affecting melanic frequencies. Some investigators attributed the discrepancy to heterozygote advantage (Clarke and Sheppard 1966, Lees and Creed 1975), but it has since been established that there is no evidence for this (Creed et al. 1980, Lees 1981, Mani 1982, Cook et al. 1986).
...
Some other distribution features were inconsistent with Kettlewell's explanation, as well. In rural Wales, the frequency of melanics was higher than expected, leading Bishop to conclude that "as yet unknown factors" were involved (Bishop 1972, p. 240). In rural East Anglia, where there was little industrial pollution and typicals seemed better camouflaged, melanics reached a frequency of 80%, prompting Lees and Creed to write: "We conclude therefore that either the predation experiments and tests of conspicuousness to humans are misleading, or some factors or factors in addition to selective predation are responsible for maintaining the high melanic frequencies" (Lees and Creed 1975, pp. 75-76).
http://www.arn.org/docs/wells/jw_pepmoth.htm
Why did darker moths increase wildly in population to 80% of the moth population in areas with no substantial industrial pollution?
Please explain that.
What role did bats and bat populations play during this period?
What are the differences besides coloring of these different moths? Do some moths fly differently, are quicker, etc,...?
This message has been edited by randman, 11-20-2005 11:50 PM

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 54 of 350 (261726)
11-20-2005 11:54 PM
Reply to: Message 53 by RAZD
11-20-2005 11:47 PM


Re: Repeated claims do not make em more valid,
More.
In the United States, the first melanic peppered moth was reported in Philadelphia in 1906, and melanism increased until by 1959 it was over 90% in some areas (Owen 1962). Yet the geographical distribution did not fit the classical story any better than it did in the U.K. (Figure 3). In the 1970’s, the frequency of melanics in a seemingly unspoiled forest in southwestern Virginia was more than double the frequency at polluted Blacksburg, 18 km away. The difference was not related to lichen cover, and could not be explained by pollution levels or gene flow (West 1977). In a low-pollution area in central eastern Pennsylvania, melanics remained at about 52% from 1971 to 1978 (Manley 1981), and in western and central Massachusetts melanics persisted at low frequencies even though the trees there were neither devoid of lichens nor blackened by soot (Sargent 1974, Treat 1979). In southeastern Michigan, the frequency of melanics was over 90% in the early 1960's, then dropped to less than 20% by 1995 (Grant et al. 1995), thus paralleling the decline of melanism in the U.K. Yet the decline in Michigan "occurred in the absence of perceptible changes in local lichen floras" (Grant et al. 1996, p. 351).
Recently, Grant and his colleagues reported a good correlation between sulfur dioxide levels and melanic frequencies in southwestern Virginia, central eastern Pennsylvania, and southeastern Michigan. In fact, the decline of melanism in both the U.S. and the U.K. appears to be "correlated primarily with reductions in atmospheric sulfur dioxide" (Grant et al. 1998, p. 465). The lack of correlation between between melanic frequencies and lichen cover, however, is a serious problem for the theory that industrial melanism is due to cryptic coloration and selective predation. This aspect of the story warrants a closer look.
http://www.arn.org/docs/wells/jw_pepmoth.htm
How do you explain more increases in darker moths in areas with less pollution? That's the opposite of what the original claim was, and yet there are numerous studies verifying this.
Talkorigins, I note, dismisses this with the claim, well, the fact is continent wide darker moths increased with more pollution, but isn't that simplistic?
If non-polluted areas where trees are not darkened saw a greater increase in darker moths than sooted areas, isn't that data that contradicts the claims that soot on trees is the causal factor?
Can you answer any of these questions without just saying you think they are ad hoc or some other nonsense?

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 56 of 350 (261731)
11-21-2005 12:29 AM
Reply to: Message 55 by RAZD
11-21-2005 12:05 AM


Re: my response, bad as it was the first time and worse for repetition.
finally did some homework...?
I am sorry, but that's pathetic. You made claims that were not backed up. I knew they were not backed up, but rather than honestly back up your points, you refused to do so and insist I back up mine.
Pretty much, I would expect a full retraction and apology, but frankly, I don't think you have the integrity within you to do so, and yes, I am more than a little ticked off. It's just flat out wrong, the whole way you proceed to present something unsubstantiated and then demand someone like me do YOUR HOMEWORK, wasting my time and your's rather than when I bring up a point in response to your OP, you dig into it and support it.
Take the bat issue. It's not up to me to figure out the role of bats and birds. It's your OP. You should do more than lightly dismiss the fact that the major predators are not mentioned in your studies.
You need to dig into the issue, and respond to these points and try to figure out whether the issue is relevant or not. Heck, for all we know, bats prefer dark colored moths more for taste or whatever and there was a decline in bat population that caused all this.
We don't know because your sources make unfounded claims that don't tell us. So do some real research and come back and tell us where these issues are addressed.
I hope I am surprised tomorrow but I won't hold my breath.

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 58 of 350 (261774)
11-21-2005 2:31 AM
Reply to: Message 57 by arachnophilia
11-21-2005 12:49 AM


Re: my response, bad as it was the first time and worse for repetition.
And? You say the primary predator is of no consequence? How do you know that?
Don't you have to offer real evidence for that?
For example, maybe some bats preferred the lighter moths and could distinquish them by their flying patterns, or maybe they craved the melatin or whatever made the darker moths dark, and there was a reduction in the bat population and so the darker moths were not eaten as much by bats?
How can you claim this is valid science without ruling out all the various potential causes?

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 60 of 350 (261782)
11-21-2005 3:06 AM
Reply to: Message 59 by arachnophilia
11-21-2005 2:41 AM


Re: my response, bad as it was the first time and worse for repetition.
does a moth's color affect its likeyhood of being eaten?
I don't know. Do you? Presumably there is a chemical that makes some moths darker. Have the studies ruled out whether or not some bats or other predators crave darker moths based on whatever makes the moth dark.
Also, it's not up to me to come up with data here. These are your claims. Where do the studies show they considered other possibilities?
Isn't that what you have to do to make a scientific claim?
because, for the fifth time, i'm not talking about causation.
Then what are you doing arguing on a thread discussing causation?

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 62 of 350 (261785)
11-21-2005 3:36 AM
Reply to: Message 61 by Modulous
11-21-2005 3:16 AM


Re: Natural selection
Here's some quotes on what evolutionists were saying about peppered moths.
A huge shift in the population’s average colour had taken place, from light to dark, within a few decades. Kettlewell called this “the most striking evolutionary change ever witnessed by man” (Kettlewell 48).
Many other evolutionists have made similarly enthusiastic comments:
The peppered moth story is “the single best-known evolution watch in history” (Weiner 271).
“The peppered moth, Biston betularia, is rightly regarded as a striking example of adaptive change through natural selection and as one of the foundation stones for the modern synthesis of evolutionary theory” (Brakefield 376).
“Typical [light], intermediate and melanic [dark] forms of the Peppered moth Biston betularia . . . furnish one of the best known examples of evolution taking place before our eyes” (Blaney 137).
“One of the most intensively studied examples of cryptic coloration [i.e., camouflage] is that of the peppered moth Biston betularia. . . . This is perhaps the most frequently quoted example of evolution in action” (Rowland-Entwistle 76).
“Organisms can adapt to moderate amounts of certain forms of pollution: the spread of industrial melanism [darkening] in peppered moths and other insects, and of heavy metal tolerance . . . in certain plants, have provided some of the most convincing evidence for evolution by natural selection” (Skelton 954).
http://www3.telus.net/csabc/PepperedMoth.html
So evos claimed this was "evolution in action"? Well, was it? Did even speciation occur?
The answer is no, it did not.
Also, check this out where prominent evolutionists admit the studies are inaccurate and do not show natural selection.
It now turns out, however, that Kettlewell’s experiments may not have even demonstrated natural selection. In the mid-1980s, biologists discovered that peppered moths only rarely rest on tree trunks in the wild. These night-flying moths are now thought to rest during the day beneath small branches high up in the trees, where they can’t be seen. Since Kettlewell released moths during the day onto exposed tree trunks, where the dazed insects froze in place and became easy targets for birds, his results may have had little bearing on what happens under natural conditions.
Hooper’s book lists many other flaws in the classic story, as well. For example, the major predators of peppered moths are probably not day-flying birds, but night-flying bats. Furthermore, Kettlewell measured camouflage by his own eye, even though research has shown that bird vision is quite different from human vision. He and Ford also disregarded the possibility that selection might have operated--not on adult moths-- but on caterpillars, through differences in their ability to withstand pollution.[3]
For these reasons (among others), a growing number of biologists have become critics of the classic peppered moth story. In 1998, University of Massachusetts biologist Theodore D. Sargent and two colleagues wrote in the journal Evolutionary Biology that although the camouflage-predation explanation “may be true, in whole or in part,” there is “little persuasive evidence, in the form of rigorous and replicated observations and experiments, to support this explanation at the present time.” The same year, University of Chicago evolutionary biologist Jerry A. Coyne wrote in Nature that the fact that peppered moths do not rest on tree trunks “alone invalidates Kettlewell’s release-and-recapture experiments, as moths were released by placing them directly onto tree trunks.” Coyne concluded that this “prize horse in our stable of examples” of evolution “is in bad shape, and, while not yet ready for the glue factory, needs serious attention.”[4]
Desperately Defending The Peppered Myth | Discovery Institute
When I say I agree natural selection exists, that really isn't that the changing moth population has anything to do with soot. It's just that by definition, all changes can be considered natural selection. It's a little dishonest therefore to try to take that concession as some sort of agreement with evolution, and that's the problem with you evos here.
You are not being honest in your approach. If you define evolution as mere change, then automatically evolution is proven, and all change has some cause and so since there is a cause, you can call all change natural selection in a loose sense.
But when we debate "evolution", we are talking specific models of ToE, and so the fact you can define evolution or natural selection as any change does not mean that just because we accept change occurs, which is obvious by daily life not being identical, then it is dishonest to claim somehow evolution being verified in the sense of any change means evolution meaning ToE is somehow supported.
This message has been edited by randman, 11-21-2005 03:38 AM

This message is a reply to:
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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 63 of 350 (261786)
11-21-2005 3:41 AM
Reply to: Message 61 by Modulous
11-21-2005 3:16 AM


like learning santa claus isn't real
So where do they spend the day? British scientist Cyril Clarke, who investigated the peppered moth extensively, wrote:
But the problem is that we do not know the resting sites of the moth during the day time . . In 25 years we have found only two betularia on the tree trunks or walls adjacent to our traps (one on an appropriate background and one not), and none elsewhere.11
The moths filmed being eaten by the birds were laboratory-bred ones placed onto tree trunks by Kettlewell; they were so languid that he once had to warm them up on his car hood.12
And all those still photos of moths on tree trunks? One paper described how it was done”dead moths were glued to the tree.13 University of Massachusetts biologist Theodore Sargent helped glue moths onto trees for a NOVA documentary. He says textbooks and films have featured ”a lot of fraudulent photographs.’14
Other studies have shown a very poor correlation between the lichen covering and the respective moth populations. And when one group of researchers glued dead moths onto trunks in an unpolluted forest, the birds took more of the dark (less camouflaged) ones, as expected. But their traps captured four times as many dark moths as light ones”the opposite of textbook predictions!15
The University of Chicago’s Jerry Coyne said that such painful revelations about the moth story (”the prize horse in our stable’) was like finding out that Santa Claus was not real.
http://www.answersingenesis.org/home/area/re2/appendix1.asp

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 68 of 350 (261796)
11-21-2005 4:24 AM
Reply to: Message 66 by mark24
11-21-2005 4:14 AM


Re: Good Grief, Charlie Brown
Natural selection is evolution, as it results in change over time. So if the experiment shows natural selection, it also shows evolution.
Can you not see why this smacks of deception to me? Your stance is the evo stance, but honestly, science textbooks are not about evolution in this sense.
Under that definition, Young Earth Creationists are evolutionists.
To interchange a loose term "evolution" with a definite term for a specific scientific theory also called "evolution" all jumbled up together is something we critics object to and think is dishonest and misleading.
What is under debate is ToE, which is universal common descent modeled based on evolutionary models. It's not "evolution" in the sense of just "change." No one has ever claimed the world doesn't change.
So if there is no speciation, and really no macroevolution, then the peppered moth story is not "evolution in action" as evolutionists claim, and moreover, the premise is shown to be faulty.
We all were taught the tree trunk story, and now we know that was wrong. Wrong too are a whole host of claims in the scenario. For example, studies also show that in some places with no pollution, the increase in darker moths was more prevalent.
But getting back to your post, switching between the theory of evolution and then the theory that change happens since evolution is mere change, is inherently deceptive and just plain wrong.
This message has been edited by randman, 11-21-2005 04:26 AM

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 69 of 350 (261798)
11-21-2005 4:29 AM
Reply to: Message 67 by Nuggin
11-21-2005 4:19 AM


Re: If it is natural selection, what is false about protraying it as natural selectio
Clearly natural selection is happening with the moths.
What is not clear is what is causing the natural selection. There really isn't evidence it was soot on tree trunks. Sometimes, there were more increases in darker moths where there was little pollution and no soot. The moths also did not rest on tree trunks.
All we have solid evidence for is that the moth population changed, something that is not that unusual and is not specific evidence for evolutionary theories anymore than any other theory.

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 97 of 350 (262166)
11-21-2005 8:18 PM
Reply to: Message 96 by RAZD
11-21-2005 8:06 PM


Re: homework, insults and substantiation
I look forward to your responses to the material, and yes, I have thrown out too many insults. My only defense is I did not draw "first blood" so to speak.

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 99 of 350 (262231)
11-22-2005 12:01 AM
Reply to: Message 98 by RAZD
11-21-2005 11:20 PM


Re: homework, and results.
There is no reason to expect one form to be "completely replaced" ...
He's quoting studies that apparently convincingly make that case. Admittedly without access to the studies he cites, we cannot easily examine their methodologies, but bare assertions that "there is no reason to expect" is nothing but a bare assertion without documentation. He backs up his claim with a citation. It may not be accurate, but it is more than a bare assertion as your claim is.
I think we can safely say that the populations of the different varieties still showed a shift from typica to carbonaria within this study area
That's the point. There should be no shift in areas not polluted if sooty tree trunks is a determinative factor. Therefore, it is reasonable to conclude bird predation changes due to sooty tree trunks are not the cause here.
All this correlation does is replace "soot" with a more specific pollutant, SO2, as the major player in the industrial pollution affecting the environment of these moths.
Sulfur Dioxide (SO2) and ionic Sulfate (SO4=) are by-products of coal-burning industrial pollution. They are particulate pollutants in the atmosphere and have also been linked with acid rain ... due to burning coal with high sulfur content.
The point is there is not a coloration issue, and so darker tree trunks favoring darker moths could not be in play. Keep in mind this fact, darker moths grew in percentages of population in areas with no discoloration due to sooty trees. You dodged that whole point with several paragraphs that appear to me to be out of place. The results are reversed in some areas.
Is this a situation where the data doesn't matter at all? You guys are going to insist the hypothesis is right no matter what the data?
Particulate sulfur also is well known to inhibit visibility in the air (haze\smog), and it can occur naturally as well as come from pollution.
How does that favor darker moths? If anything, it would favor lighter moths. But you make a good point that bird vision is not mentioned.
It may well be that the {presence\absence} of SO2 and SO4= particles changes the apparent color of the environment -- relative to bird vision and the apparent color of the different varieties of the moths -- and that this is all that is needed for the natural selection to occur.
It may be indeed, or may not be. Too bad the original study does not take this into account, and that evos are so wed to the original study's claims that in arguing for it, they ignore this area.
All that says to me is that there is no conclusive evidence one way or another that bird predation changes are a significant factor in the emergence of darker moths, especially since this occurred in wide regions with very little to no soot accumulating on trees.
As you say, "it could be"?
Too bad, evos haven't come up with anything conclusive here.
No other mechanism has been proposed that provides this level of explanation for the observed population shifts.
That may be so, but I think we can safely rule out sooty tree trunks making lighter moths more visible to birds. Don't you agree?
Otherwise, why did darker moths increase in areas with no sooty tree trunks?
Given that he is a critic of "icons of evolution" and given that he still cannot rule out selective predation means that there is still a very strong case for the evidence that has been observed in the studies -- and that the conclusions have not been invalidated, just questioned.
Questions do not invalidate theories. Facts do.
You mean like the fact vast swaths of land with no accumulation of soot on trees also experienced the same phenomena?
You err and thinking Wells is like you. He is just being objective as a scientist and stating that there could still be some other selective pressure we don't know about, but he effectively rules out the sooty tree trunk story since it does not jive with the facts.
Oh, and Occam's razor is not a fact. Moreover, the simplist explanation is that where there is no soot on trees, claiming sooty tree trunks led to increased bird predation of lightly colored moths is quite absurd.

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randman 
Suspended Member (Idle past 4920 days)
Posts: 6367
Joined: 05-26-2005


Message 101 of 350 (262237)
11-22-2005 12:13 AM
Reply to: Message 100 by arachnophilia
11-22-2005 12:07 AM


Re: wait. i'm lost.
and now razd is saying that this article has the unreasonable expectation of a localized extinction (and therefor speciation).
The studies he cites suggests IF the scenario were true of increased bird predation feeding on lighter colored moths, that they should have died out in some areas. He doesn't state why the studies say that. I would venture a guess that due the rates of increase in darker moths, but unfortunately, unless one is extremely well verses and has read those studies, the article does not delve into the detail of them.

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