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Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: Peppered Moths and Natural Selection | |||||||||||||||||||||||
Dr Adequate Member (Idle past 311 days) Posts: 16113 Joined: |
Than it is necessary to make serious research where moths really rest, while in a green foliage it is much difficult to see any cryptic advantage of melanism as in a poluted bark. http://www.weloennig.de/BistonA.html#1a As your link points out, their most common resting position is on the underside of branches, where the same camouflage would be useful as on trunks. Please note also that this whole question of whether they roost on trunks is irrelevant to most of the studies, including all of Kettlewell's studies, none of which involved the fixing of moths to tree-trunks. "A stupid man's report of what a clever man says is never accurate because he unconsciously translates what he hears into something he can understand." --- Bertrand Russell
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Let's take the evidence of the Kettlewell studies eh?
http://bsgran.people.wm.edu/melanism.pdf:
quote: We can probably agree that human eyes do not see like bird eyes so the relevance of STUDY (1) is somewhat moot, that at first blush it at best indicates a tendency for different appearance to birds. Yes? STUDY (2) though, clearly, distinctly and unambiguously demonstrated that birds preferentially ate dark moths on light trees and light moths on dark trees. This alone is sufficient, btw, to invalidate your pet concept as it demonstrates the benefits of {camouflage\mimicry} without any of the rest of the studies being needed. Note too that this actually confirms the results of STUDY (1) - it demonstrates that the birds do in fact more easily distinguish dark moths on light backgrounds and light moths on dark backgrounds, as noted by Grant in the above linked article:
quote:(color for emPHAsis) Study (3) demonstrated that moths released and then recaptured also suffered the same pattern of loss -- regardless of where they actually perched during the day -- with dark moths being preferentially reduced in numbers by predation in unpolluted (light) forests and light moths being preferentially reduced in numbers by predation in polluted (dark) forests. Note that the same proceedure was used in each type of forest so that the only difference in the results is due to the relative predation of the diffeent varieties of moths during the period between release and capture, and the only difference between the two release and capture programs was the different relative camouflage one variety of moth versus the other. In both cases the variety that more closely mimicked the prevalent bark coloration survived in greater numbers than the variety that didn't match the prevalent bark color.
47 observed moths during years 1964-1996 (1,5 observed moths/year) Argument from incredulity is a logical fallacy. A response in kind would be on the order of: Have you ever tried to find moths in the wild in a woods during the day? Ones that are normally well camouflaged? The first question for you to answer, then, is where did they rest if not in the trees? The second question is two part:
So far no other mechanism has been proposed that explains the evidence. Until such a mechanism is proposed and tested then complaining about the actual numbers of moths sighted in various locations is just clutching at straws in the light of the abundant, clear, distinct and unambiguous evidence of preferential predation by birds. Also note that not all the moths need to rest on the bark for the pattern of preferential predation to be observed, just enough of them that the overal population shows preferential predation. This is the validity of the different proportions of moth sighting in different locations -- it shows some known variations in places naturally chosen by moths for resting and that SOME are on bark. The proportion that naturally rest on bark could in fact be substantially higher if (1) even experienced observers have trouble distinguishing immobile well camouflaged moths and (2) moths that are not that well camouflaged have already been consumed (by the proverbial early bird eh?).
About second example near traps I do not know more details ... so I preliminary restrict to the first one that seems to be more connected with real conditions. Light was used to attract the moths (a well known tactic eh?) so the population of moths was artificially concentrated around the lights. Within that concentrated pattern there were more moths found than in the wild. This could just be a measure of a greater dispersal of the moths in a natural environment versus a lit one, but doesn't mean that the moths were perched in "un-natural" locations around the lights -- the fact remains that the basic pattern is the same between Majerus's 47 finds and the light concentrated 203 finds, and in both cases the predominant resting place was on bark.
Surely I would appreciate if you instead of common discourtesy and emphasizing your unfounded propositions with highlited letters give some scientific relevant links/facts ... Courtesy also involves dealing with the evidence provided, the links for further investigation, and answering points that make your pet concept invalid. Seeing as all the colored highlights are well backed up by references and are highlighted to emphasize the points that you are trying desperately to deny, there is nothing "discourteous" in pointing out such denials and oversights. The peppered moths are an example of natural selection based on the preferential predation of less camouflaged moths, and this shows a clear, distinct and unambiguous survival benefit to moths that better mimic parts of the environment. Now you could be courteous and acknowledge that your concept is indeed invalid, and that there is in fact a demonstrated benefit to mimicry, that such mimicry can indeed be selected for through natural selection mechanisms and that this is sufficient to explain the population shifts in the peppered moths in particular, and the development of other mimicry patterns in general. Enjoy. we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Study (3) demonstrated that moths released and then recaptured also suffered the same pattern of loss -- regardless of where they actually perched during the day -- with dark moths being preferentially reduced in numbers by predation in unpolluted (light)forests and light moths being preferentially reduced in numbers by predation in polluted (dark) forests.
This proposition seems be right at first moment but let us go deeper. According Grant moths in these demonstaration were released during day, in morning and:
Moths released during daylight hours do not behave normally, and if prompted to fly, they will settle quickly on just about the first thing they encounter. In my view, the greatest weakness of Kettlewell's mark-release-recapture experiments is that he released his moths during daylight hours. Neverthenless Grant gave following explanation, and you have given this explanation somewhere in beginning of this thread too:
So, if he was wrong to use the trunks of trees in Birmingham, he was consistently wrong to use the trunks of trees in Dorset. If he was wrong to release the moths during the daylight hours in Birmingham, he was consistently wrong to release the moths at the same time in Dorset. His data, however, show that the variable of regional pollution made a significant difference as to which phenotypes of the moths better survived the conditions imposed by the experiments.
With this explanation I can hardly agree. Let us assume that peppered moths normally spend nights in foliage in canopy. Now they were released during day and they encountered predominantly - letus assume - trunks, where they stayed: at dark barks pale specimens were picked predominantly and vice versa - at pale barks were picked darker specimens by predators. So in different poluted area outcome of this experiment may be really supportive for selectionism and neodarwinism. But the experiment might have no connection to real conditions, because it would be necessary to ensure, that moths spend daytime approximatelly at same places as when they choiced their placesduring night (dawn) on their own. Experiment would had have some meaning, if moths would have been released at beginning of night and recaptured after one-two days. But according Grant this is impossible due:"This solution might seem obvious and easy to recommend, but it's not easy to do. The return rate two days after release drops off enormously as a result of either mortality or dispersal from the trapping area." Summary - if in Kettlewel experiments moths rest in different places as they rest normally, experiment support nothing. And we should not forget, that according another experiment "Kettlewell (1955b) reported morph specific behaviors: carbonaria tended to settle on black, and the typicals tended to settle on white." Then - if true - I do not see selective pressure not even so strong, because moths find least conspicuous places for them.
You need to provide a rational alternative scenario that explains the evidence eh?
What evidence? We do not know where pepered moths rest during day. If they rested for instance in holes, than I will not see any selective pressure on them from birds because of darkness.If they rest predominantly in foliage in canopy is selective difference between pale/dark ones as strong as when they rest on barks? That would mean that selection is not responsible for melanism and the phenomenon should be explained by different cause. Because we do not know where peppered moths rest, no experiment has scientific value untill during its course peppered moth are proportionally in same places on trees as usually they are during their daily rest. citation from Grant are in:"Fine Tuning the Peppered Moth Paradigm"
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
With this explanation I can hardly agree. Of course you can ... unless you are intellectually incapable of seeing\believing that your pet concpet is really invalid eh? So you are saying the experiments do NOT show preferential predation? Have you developed an alternative explanation for all the evidence yet?
What evidence? The evidence of changes in population proportions, not just in the overall observed numbers, or in the Kettlewell experiments, but in ALL the experiments and observations, including the ones that link it to (a) bird predation and (b) camouflage ability. According to Grant (Fine Tuning):
quote:(color mine for empHASis again) The information is there.
Because we do not know where peppered moths rest, no experiment has scientific value Logically false. We may not know where they rest all of the time but we do know where they rest some of the time. Why? because at least 47 moths have been found in those locations in a totally wild environment and 203 moths have been found in those locations after being attracted by light traps to the general area (concentrated). We don't need to know ALL the locations, only that SOME are used that have the properties in question where the effect has actually clearly, distinctly and unambiguously been shown to occur. We also know that they use a variety of resting locations, and that there is a very good reason for using a variety of locations (Grant again, same source):
quote: The predators would learn the common resting places, whether it was holes or any other location you can think of. From Majerus himself in Re: Peppered Moths - in black and white (part 2 of 2) (you may also want to read Re: Peppered Moths - in black and white (part 1 of 2) and A Peppered Epilogue):
quote:(color mine for empHASis, capitals his in the original.) The fact is still that the evidence clearly, distinctly and unambiguously, shows preferential predation by birds of moths dependant on their different camouflage ability. Denial does not make the evidence go away. Clutching at straws does not make the evidence go away. If you want the evidence to go away you need to provide an alternative mechanism that explains the evidence -- so far all you have is hand waving shuck and jive. Enjoy. Edited by RAZD, : ptyo we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
RAZD writes:
quote:-------------------------------------------------------------------------------- While the trunk/branch joint was the most common site, his data indicate that the moths do not all rest in the same place. As Clarke et al. (1994) put it: "Moths habitually resting in only one place will be habitually sought there." Do you deliberately snatch this piece of text? Because Grant only summarized previous researches to come to conclusion:
In truth, we still don't know the natural hiding places of peppered moths.
http://bsgran.people.wm.edu/melanism.pdf By the way it seems to me very strange, that Majerus during 33 years found only 12 moths resting on trunks in free nature (25% of 47) - and this is the only argument supporting thesis, that they rest on trunks at all.Because according another source - Mikola:
(1979, p. 86 Of about 100 lepidopterists present at a monthly meeting of the Finnish Lepidopterological Society, nobody had ever found the species in day-rest on tree trunks. Similarly, lepidopterists in Germany have wondered why the species is hardly ever found on trunks, if these constitute the main resting place of the species (G. Ebert and S. Wagner, oral comm.).
http://www.weloennig.de/BistonA.html#1a So if somebody believe, that they rest on truks, it is only darwinian faith with no serious scientifical backround. You sended some links to Majerus from 1999, but I have found Cambridge latest Majerus comments from 2004: Page not found | Department of Genetics I reccomend everybody to read it. Especially interesting is Majerus conclusion:
We may take certain observations of the peppered moth as fact (PP23). i) From numerous breeding experiments, both published and unpublished, it is incontrovertible that the forms of the peppered moth are inherited according to Mendel’s laws of inheritance. ii) The frequencies of f. carbonaria and f. swettaria (the melanic form of the peppered moth in North America), have varied both temporally and spatially. iii) There has been and is a correlation between carbonaria frequency and pollution levels, particularly sulphur dioxide levels. iv) The observed changes in the frequencies of forms of the peppered moth, both in the nineteenth century, and currently are too rapid to be accounted for by random genetic drift. These factual observations are sufficient to provide evidence that natural selection has had a role in the rise and fall of carbonaria.
Do you see that saltus, that while "are too rapid to be accounted for by random genetic drift"than it must be due selection? Even if I agree - and I do not have problem to - with all 4 propostions I do not see implication. No proof, no cited experiments, only the claim. As I wrote before, there exist no experimental proof of selection, because moths released during experiments in the morning did not rest in same positions as naturally but on first ones they encounter. And from such distorted conditions it is utterly unscietific to draw any conclusions. Majerus gives there also some interesting facts I did not know before:1) That according Kettlewell 90% of eaten moths are eaten by bats. 2) Majerus supports Kettlewel claim, that carbonaria and betularia search crzptic position during day - acrbonaria dark backround, betularia pale. As to the second point it is necessary to appreciate it if true - it means, that for birds it would be more difficult to find them as when they rest on same backround - selective pressure would be diminished. And now - if according Majerus 25% of 47 moths rested on trunks and according Kettlewel 90% of moths are eaten by bats, than only 10% mortality of moths may be attributed to birds, yes? And from these 10% only quarter can be found on trunks and can be eaten by birds from there, yes?I do not underestand, how these 2% (quarter from 10%) eaten by birds from trunks may produce such attention to trunks as crucial for selection? And what if another proposition is right that moths on trunks rest very scarcely, or not at all and for instance 95% of them rested on foliage in canopy? What then? When we do not know, where moths rest and subsequently how they are crypted and subsequently selected by birds everything is only neodarwinian speculation. Instead of facts and relevant numbers we are facing only neodarwinian dialectic.
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Brad McFall Member (Idle past 5060 days) Posts: 3428 From: Ithaca,NY, USA Joined: |
This is very interesting.
I have also noticed that as soon as one begins to read actual population genetic "language" and literature, "too much" is often made of terms such as "spatial and temporal." The entire difference between Fisher and Wright boils out for example, to what these words mean IN DETAIL for each population being modeled. I have noticed in that case, that Mayr's insistance on allopatric neontology (and hence Gould's subsequent clutching"" to it for Punctuated Equilibrium after criticism from within biology) *Might* ( it is only my hunch) be due to his favoring Wright during a "run-in" with Fisher while he was editor of "EVOLUTION" (the journal) (This is discussed in Provine's book on Sewall WrightPage Not Found - University of Chicago Press). Edited by Brad McFall, : added link
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
By the way it seems to me very strange, that Majerus during 33 years found only 12 moths resting on trunks in free nature (25% of 47) - and this is the only argument supporting thesis, that they rest on trunks at all. Oops, your denial is showing again. Lets check the facts again eh? http://www.talkorigins.org/...ls/images/majerus_table6_1.gif
You also seem to invest a lot of personal incredulity in the fact that he only found 47 in 33 years of study. Nowhere does it say that he was doing a population survey to find all the places, so these would be happenchance findings during the course of the studies. He also does not claim that these are the only places they rest. Ever gone looking for moths yourself? We (2 bros + dad) used to have a {butterfly\moth\bug} collection when I was a kid that covered a 4ft X 8ft board. Not one of the moths was found resting immobile on a tree. You don't notice things that don't move particularly if they are camoflaged. Let's also look at the other data from the 203 moths found in one year near the light traps:
Now let's deduct the man-made surfaces moths from the data to see the relative proportions of natural resting areas chosen by the remaining 178 moths:
As noted previously all that is needed is for SOME of the moths to rest on lichen covered bark areas for there to be a benefit to the camoflage, and in these data we see 7 out of 8 moths resting in such areas. That's more than "some" of the moths, that's "most" of the moths eh? Note (1) that ALL of the released moths flew up into trees in the moth release studies, and (2) that 7 out of 8 moths chose resting places on lichen covered bark surfaces of ALL the available surfaces in the nearby trees.
Because according another source - Mikola: (1979, p. 86) Of about 100 lepidopterists present at a monthly meeting of the Finnish Lepidopterological Society, nobody had ever found the species in day-rest on tree trunks. Similarly, lepidopterists in Germany have wondered why the species is hardly ever found on trunks, if these constitute the main resting place of the species (G. Ebert and S. Wagner, oral comm.). Note that they only address tree trunks, and do not discuss at all the trunk\branch joints, branches and foilage -- a sin of ommission and thus a logical fallacy (red herring). Note that 75% of Majerus's moths were found on bark areas that were not trunks and 48% of the light trap local moths were found on bark areas that were not tree trunks ...
... ie -- it is entirely possible to have zero moths on trunks and still have the selective effect because of the moths resting on non-trunk lichen covered bark areas (or other lichen covered areas), ... because the issue is that the camouflage is like the lichen covered bark (or other lichen covered areas) -- where ever there is lichen covered bark (or other lichen covered areas). Focusing on just the trunks ...
So if somebody believe, that they rest on truks, it is only darwinian faith with no serious scientifical backround.
... is called the logical fallacy of the straw man argument. The issue is NOT whether they rest on trunks but on lichen covered surfaces. They do. See data above that demonstrates clearly, distinctly and unambiguously that they do in fact rest on lichen covered bark surfaces. (They may also rest on other lichen covered areas ... lichens don't only grow on trees eh?)
Do you see that saltus, that while "are too rapid to be accounted for by random genetic drift" than it must be due selection? The rate of change is faster than has been observed for any population undergoing genetic drift, much faster. Waaay much faster.
Even if I agree - and I do not have problem to - with all 4 propostions I do not see implication. If you have a problem with the logical development of the argument then dissect the logic and show where the error lies. If you CANNOT dissect the logic then you CANNOT challenge the conclusion based solely on your ignorance and incredulity. This is the same as claiming that the sun orbits the earth as far as validity goes. You state you have no problem with "all 4 propositions" therefore you admit that the conclusion is valid, but then you still deny it. This is the mark of delusion eh?
quote: Belief in something in spite of evidence to the contrary is delusion. One can be deluded by others, however when one is confronted with the facts, the evidence, the truth, of the matter and still holds a belief in denial of the {facts\evidence\truth}, then one is psychologically deluded - living in a state of delusion about the reality of the world. See Definitions, Daffynitions, Delusions, Logic and Critical Thinking. for a further discussion of this element of thinking, and then consider your position. Do you have any alternative theory that explains the facts? Do you have any legitimate criticism of the logic of the argument? If the answer is no to both and you still maintain that the conclusions based on the evidence is false, then it is not because you have any rational cause based on the evaluation of the evidence and the logic.
No proof, no cited experiments, only the claim. Proof. Again you demonstrate a lack of knowledge about science. Science does not prove theories. Science tests theories, and if they don't pass the test they are invalid (as your pet concept is invalid - theories can be disproven), but if they pass the tests they are not "proven" just validated by the test, and have to move on to the next test. Not ONE of the studies (each a test of the theory) involved has invalidated the theory that the change in population is due to preferential predation of the different varieties of moths by birds due to their differing camouflage ability in the different environments. Note the way Majerus states his conclusion:
quote: That is the logical conclusion based on the evidence available to date. He knows the experiments and the data even if you don't eh? Heck, even AIG reach the same conclusion.
Majerus gives there also some interesting facts I did not know before: 1) That according Kettlewell 90% of eaten moths are eaten by bats. So? Unless they are able to distinguish Biston betularia typica from Biston betularia carbonaria (please notice that BOTH are "betularia" -- that is the species name), such predation will have no preferential effect on the population but will consume moths in proportion to their populations and cause no change in population proportions. Seeing as any such ability would work in the SAME direction for preferential predation of flying moths, then there would be no DIFFERENCE in the population change results for the two opposite changes in environment, both would end up with either mostly typica or mostly carbonaria: seeing as this is not the case, this hypothesis is invalidated. By the evidence. Therefore bats are not a factor in the observed change in population proportions. (See how that works eh?) All that is needed is for preferential predation by birds of SOME of the moths for it to affect the population proportions. That too is what the evidence shows. Does that "prove" the case? No, because science doesn't prove theories. Does that validate the theory? Yes.
2) Majerus supports Kettlewel claim, that carbonaria and betularia search crzptic position during day - acrbonaria dark backround, betularia pale. So. Now you are essentially using the fact that moths rest on lichen covered bark to show that they don't rest on lichen covered bark?
As to the second point it is necessary to appreciate it if true - it means, that for birds it would be more difficult to find them as when they rest on same backround - selective pressure would be diminished. Except you are assuming they can FIND suitable resting places eh? You of course realize that in a polluted forest there is virtually NO light background area for typica moths to rest on, no matter what their 'preference' is in the matter? You also realize, of course, that in a non-polluted forest of the kind studied there is very little dark background area for carbonaria moths to rest on, no matter what their preference is in the matter? And you -- of course -- realize that this leaves the non-camouflaged variety in each case ill equiped to evade preferential predation by birds during the daylight hours regardless of how many moths are eaten by bats.
This is, after all, the issue -- that the environment changed ... ... changed such that the population that previously enjoyed a selective advantage for better suited camouflage for the predominant environment found they were no longer better adapted to the prevalent environment and were vulnerable ... ... changed such that the population that previously lived in the fringes of the other population with less well adapted camouflage found they were now better adapted to the prevalent environment and now THEY enjoyed a selective advantage for being better suited. And what if another proposition is right that moths on trunks rest very scarcely, or not at all and for instance 95% of them rested on foliage in canopy? What then? You still have SOME moths resting on lichen covered bark areas where they are clearly, distinctly and unambiguously subjected to preferential predation by birds during the day. Even if the only ones resting there are ones well camouflaged for the particular environment -- typica in light unpolluted forests and carbonaria in dark polluted forests and all the others (both varieties) are resting in the canopy. You have still not invalidated the theory or the conclusions, all you have done is repeated your personal incredulity and ignorance ... and denial. AND, if you are interested in science, then what you do is come up with an alternative theory for what was going on that equally explains the data that was observed for the population changing proportions to match the prevaling environment, and then you go out and test that theory. That is if you are intersted in science. There is still a complete VOID of alternative explanation for the observed change in populations. There is no competing theory to test, and there is no logical criticique of the conclusions reached to date to show that they are invalid. There is no alternative explanation.
... everything is only neodarwinian speculation. Instead of facts and relevant numbers we are facing only neodarwinian dialectic. Yes, you are faced with data and logical conclusions, tested theory and validated results ... and an explanation that works, that explains the data, explains the observations ... better than any other explanation ... (which is what science does eh?) ... whether you personally desperately and willfully deny them or not. All you have is incredulity and ignorance and denial. Especially your denial that the observed data from ONE study clearly, distinctly and unambiguously totally invalidates your pet concept that mimicry has no selective advantage. Note as well, that your personal denial of the evidence for natural selection in this particular case puts your particular views in the far fringes of even what one could call "mainstream" creationist thought, ... which is not known for being central to scientific thinking (or even logical thinking ... or even factual thinking). Enjoy. Edited by RAZD, : added one line we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Oops, your denial is showing again. Lets check the facts again eh?
I agree but let me end the discussion on resting places that moths rest on trunks at best "rarely", ok?:
For example, it is now generally recognized that B. betularia rarely rest by day on tree trunks, preferring to rest higher in the canopy under horizontal branches and twigs ( Kettlewell, 1958; Mikkola, 1979; Howlett & Majerus, 1987; Liebert & Brakefield, 1987).
Citation is from Journal of Evolutionary Biology (2000): "Here" But as you seem to agree with these facts regarding rest places on trunks I have presented you so many times you with common discourtesy changed topic to this one:
... is called the logical fallacy of the straw man argument. The issue is NOT whether they rest on trunks but on lichen covered surfaces.
But question still remain - if you realize it - even if they rest on lichens, how it fall in with selection? Birds see also in UV spectrum and from the same article it is misleading to presume that there is any crypsis of peppered moths typica and carbonaria in UV light on (foliose) lichens. It goes even against crypsis, as percieved by human:
In human visible light the speckled form typica appeared cyptic when seen against a background of foliose lichen, whereas the dark form carbonaria was conspicuous. Under UV light the situation was reversed. The foliose lichens absorbed UV and appeared dark as did carbonaria. Typica, however, reflected UV and was conspicuous. Against crustose lichens, typica was less visible than carbonaria in both visible and UV light.
Normal / UV pictures of moths on foliose lichens are on the same page. I reccomend everybody to look at it if it support crypsis even a bit. "UV Crypsis" Last conclusion from the article sounds btw. as my ridiculed "pet concept" of crypsis:
...will lead to misleading deductions of the importance of crypsis, relative to other variables, in the evolution of melanism, at least in the case of the peppered moth.
Might be that there is still neodarwinian selection of peppered moths even without crypsis uf?Enjoy.
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
I agree but let me end the discussion on resting places that moths rest on trunks at best "rarely", ok?: My point is (and has been) that resting on the trunk (or not) is irrelevant, when the real question is whether (or not) they are resting on a lichen covered bark or sooty bark -- where ever that is located -- so that the patterns would be effective. A concurrent point is that "rarely" is not "never" -- sometimes for natural selection the difference can be in fractions of a percentage of cases, but that fraction of a percent is STILL a benefit that will propagate within the population. Of course the higher the percentage involved the faster the change in proportions eh?
But as you seem to agree with these facts regarding rest places on trunks I have presented you so many times you with common discourtesy changed topic to this one: I suggest before you impugn "discourtesy" that you check the relevant posts. What I have consistently said is that moths rest on bark areas (whether lichen covered or not) -- and you were the one insisting on talking about trunks to the exclusion of all the other bark areas. Now it seems YOU are in agreement that the moths rest on lichen covered bark or polluted bark areas on trees -- places where the moths will have different survival potential based on their different camouflage ability -- and not some mysterious {other} location (didn't you say perhaps a hole?).
But question still remain - if you realize it - even if they rest on lichens, how it fall in with selection? The answer is still the same: the moths have developed camouflage patterns to hide on the lichen covered bark during the day as a protection from predation by birds. The coloration has no benefit during the night because (a) the colors can't be seen and (b) they are flying rather than resting on the lichens. The answer is also still that only SOME of the moths need to rest where they have a better camouflage benefit for this to show up in the changing proportions of the populations of the two varieties of moths. Any place where the two varieties have equal {benefit\fitness} will not cause a change in proportions of the populations as predation would be proportional to population proportions -- this is the same as predation by bats having no effect on the population proportions.
Birds see also in UV spectrum and from the same article it is misleading to presume that there is any crypsis of peppered moths typica and carbonaria in UV light on (foliose) lichens. It goes even against crypsis, as percieved by human:
In human visible light the speckled form typica appeared cyptic when seen against a background of foliose lichen, whereas the dark form carbonaria was conspicuous. Under UV light the situation was reversed. The foliose lichens absorbed UV and appeared dark as did carbonaria. Typica, however, reflected UV and was conspicuous. Against crustose lichens, typica was less visible than carbonaria in both visible and UV light. Color mine for emPHAsis on the element you appear to be ignoring here. Majerus goes on at length about the difference of foliose and crustose lichens and their relevance to pollution effects and pollution recover. He also makes the point that the crustose lichens -- in unpolluted forests -- are more prevalent where the moths rest more often (but not exclusively) -- on the lichen covered bark underside of branches, yes?
ie -- the moths normally rested where the typica variety had the most visual protection from bird predation in unpolluted forests. Majerus also makes the point that pollution with sulfur dioxide and soot kills almost all the lichens of both foliose and crustose types and darkens the barks surfaces. This leaves the moths with only bark areas for resting, areas where the carbonaria would have the most visual protection from bird predation in polluted forests (as shown by previous experimental results).
ie -- the moths normally rested where the carbonaria variety had the most visual protection from bird predation in polluted forests. The environment changed from one type to the other (non-polluted to polluted and then polluted to non-polluted), and this change in environment cause a change in the fitness of the two varieties, such that the previously unfavored variety became favored and the favored variety became unfavored. Natural selection, in the form of bird predation, then caused the population proportions to change from one variety being predominant to the other variety being predominant, as the unfavored varieties were consumed in greater proportion than the more favored ones, and this changed the population proportions. Unfortunately we do not have UV pictures of moths on polluted bark areas to see if there is a difference from what we see, but lets discuss this issue of bird vision a little further:
Normal / UV pictures of moths on foliose lichens are on the same page. I reccomend everybody to look at it if it support crypsis even a bit. Note that the "normal" picture combines the three (3) color visual areas common to humans and birds, but we don't have three (3) pictures in each of those three (3) different color bands. If we did they would have similar differences as the one filtered only in UV, based on the different behavior in the different wavelengths perceived by each of the different color receptors. Further, overall perception is not simply a matter of looking only through the different receptors, as there is processing in the brain that blends the results to give us all the intermediate colors: we perceive "purple" but we don't see it. The birds are not seeing ONLY in UV, but in the total wavelength band that includes UV with the others, so NEITHER picture shows what a bird would perceive. They too would perceive a blending of all their filters to give an integrated picture, some combination of the two pictures (and not likely an average, it would likely be 1/4 UV and 3/4 for the other three (3) color receptors -- ie based on the number of color receptors in the eyes). Further, it appears that birds have 4 or more different color receptors (depending on species) rather than just {human}+UV: Document not found | Error | University of Bristol
quote: And it's not just cones that are used:http://users.mikrotec.com/~pthrush/lighting/cvb.html quote: Translation: we don't really know how birds perceive. What is the blended end perception of the different bird species involved? More to the point, how can we test for it? Easy. We put moths of different levels of crypsis as we perceive it on different backgrounds simulating natural resting places, and then see what the birds perceive by their reactions. Which is what Kettlewell did. And the results documented that typica moths on lichen surfaces were indeed detected less than carbonaria moths by the bird predators, and that carbonaria moths on polluted surfaces were detected less than typica moths by the bird predators -- confirming that the bird species in question had overall perceptions of the moths similar enough to what the people saw for there to be a difference in camouflage ability. Certainly the ability of birds to see into UV ranges did not turn the typica moths into glaring, flashing neon beacons of visibility ... as you seem to imply ... ie the perception of the birds was tested and the different camouflage ability relative to perception by the birds was confirmed to match expectations by the actual bird behavior. Finally I give you with this quote from the article that you linked but apparently also overlooked:
quote:(color mine for emPHAsis). They come to this conclusion due to the {vision including UV} camouflage ability of typica moths on crustose lichens compared to carbonaria moths and of the { vision including UV} camouflage ability of carbonaria moths on polluted tree surfaces compared to typica moths. They not only CONFIRM previous results:
Might be that there is still neodarwinian selection of peppered moths even without crypsis uf? Natural selection is an ongoing thing operating on many levels. In this instance ONE of those levels is on the benefit of better camoflage ability of one variety over the other. The fact remains that the benefits of crypsis patterns was demonstrated ... by the birds eating moths on the trees ... and that your pet concept -- that natural selection cannot influence the use of cryptic patterns -- is therefore dead in the water, invalid, null, void, caput, finished. And yes, your denial of this fact is still showing. Enjoy. Edited by RAZD, : fixed formating we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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MartinV  Suspended Member (Idle past 5856 days) Posts: 502 From: Slovakia, Bratislava Joined: |
RAZD writes:
He also makes the point that the crustose lichens -- in unpolluted forests -- are more prevalent where the moths rest more often (but not exclusively) -- on the lichen covered bark underside of branches, yes?ie -- the moths normally rested where the typica variety had the most visual protection from bird predation in unpolluted forests. What Majerus wrote is this:
It is our view that the peppered moth habitually rests by day on the undersurfaces of horizontal branches and twigs, and that its colour pattern provides an effective cryptic match...
It is just theirs view, nothing less, nothing more. No scientific research, just "our view". Let me cite also from Majerus article written 4 years afterwards in 2004, where he admits, that:
The only criticism that can be aimed at all the predation studies conducted to date is that the moths available for predation did not take up their own resting positions during the pre-dawn flight that characterizes this species. This criticism should be addressed in future predation experiments...
I do not even underestand this complaint.1) How is it possible, that after 50 years of intense study and contoversies of industrial melanism there is no serious research, where peppered moths rest during day and we are referred to sentences as "our view"? Should their rest during the experiment in same places, where we suppose them to rest normally on "our view"? 2) How is it possible, that criticism should be addressed in future experiments - article is from 2000 - but yet Majerus himself do not proceed these experiments, even though he proceeded in cited article from 2004 experiments with bats, if they pick up selective moths or no? As to the lichens, on talkorigins article on peppered moths is written:
Kettlewell, too, argued that peppered moths are well concealed on birch bark (even without lichens).
Icon of Obfuscation So according Kettlewell are moths well concealed on birch bark, so consequently I suppose same for birch twigs etc... But let us assume, that Majerus unwaranted hypothesis is right and they rest predominantly (is it right meaning for habitualy?) on crustose lichens and not on foliose lichens (it would be then of course more to topic, if he show us UV/normal photos of moths on crustose lichens instead of foliose.) Now we can move to polluted areas, where are no crustose lichens and only foliose lichens or no lichens at all. Barks are poluted, dark and so on.Why we assume, that typica would rest on places without lichens or even on dark places? According Kettlewel carbonaria and typica choose ther resting places to be inconspicuous, so we can presume, that typica in polluted forest would search for some bright places, not dark. Even in your previous post you wrote:
You of course realize that in a polluted forest there is virtually NO light background area for typica moths to rest on, no matter what their 'preference' is in the matter?
You again presented some unwaranted assumption and instead of using facts, you as usually on such occasions emphasized "eternal truth" with "NO". How are you sure, that there is no light background places? Were you on canopy, did you make any research? I doubt this hypothesis to be true. If the forest is so polluted, that there is no bright places, is there still nourishment for moths?Were it not be more suitable for them abandon such place and search something more normal, that are they used to? Are grasses, flowers, leaves, twigs, everything so dark in polluted forest as if somebody burned there cars tyres? Is such places even fit to live in? In my country in deciduous forests there can be often found birchs. Were barks of birches during industrial revolution in England also dark?But let us even assume, that environment is so polluted, that there is no bright places, birchs are not near or are dark. How we can be sure, that decline of typica in such areas are due selection and not due migration of typica to more favourable areas? Because I noticed, that sometimes discrepancies in occurence of expected neodarwinian ratio of typica/carbonaria are dismissed due migration. Why not here? Do migrate typica/carbonaria from same area always together or none of them? I would like discuss later - if you would agree too - also UV problem of predation, but still seems to me with accordance with Majerus as crucial point of peppered moth story the restingplaces and how to make such experiment. Btw. is melanism observed only on peppered moths? What about Oak beauty moths and other species that according creationists:
Oak Beauty is the Pepper moth's closest relative in England and is a trunk rester, (unlike the Pepper moth) yet the melanic form may have increased from 33-36%, but was always in the minority although it lived in the same areas as the Pepper moth.
I did not found refutation of this either on talkorigins or in Majerus articles. Is it hoax or a forgotten fact? "Creationist site on pepperd moth" Edited by MartinV, : grammar neither/nor - either/or
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
RAZD writes:
He also makes the point that the crustose lichens -- in unpolluted forests -- are more prevalent where the moths rest more often (but not exclusively) -- on the lichen covered bark underside of branches, yes?ie -- the moths normally rested where the typica variety had the most visual protection from bird predation in unpolluted forests. What Majerus wrote is this: So you concur that the typica variety is more protected by camouflage on those areas where it has been observed in the greatest proportions to be actually physically resting on the trees in question. I say this because nothing you have provided refutes this point -- that observation and data from numerous studies show that (a) "the moths normally rested where the typica variety had the most visual protection from bird predation in unpolluted forests" and (b) "the moths normally rested where the carbonaria variety had the most visual protection from bird predation in polluted forests"(color for emPHAsis). MartinV quote mining Majerus writes:
The only criticism that can be aimed at all the predation studies conducted to date is that the moths available for predation did not take up their own resting positions during the pre-dawn flight that characterizes this species. This criticism should be addressed in future predation experiments...
So you concur that preferential predation of the moths occurred, that observation and data from numerous studies show that Majerus' conclusion is valid:
quote:(color again mine for emPHAsis). Note that the worst you can get based on this criticism from Majerus is that preferential predation was demonstrated when the conditions for concealment were less than optimum for each variety, but was never the less demonstrated to be clear, distinct and unambiguous evidence of the different ability of the two varieties under contrasting situations to be protected from predation by mimicry of their background environment.(color for emPHAsis). How is it possible, that after 50 years of intense study ... Because (1) it looks like the populations of the moths is fairly small -- based on the numbers found around light traps for a whole year -- less than one a day, and small populations makes individuals hard to find, and (2) because it is not that critical to the studies (whether you think it is or not) -- preferential predation was demonstrated, preferential predation was observed, and no other mechanism has been proposed that can account for the data and observations. Small populations also make changes in proportions more visible\observable\apparent. How is it possible that you have not done any studies yourself to answer this vital question? How is it possible that creationists have not done any studies that should so easily disprove an "icon" of evolution when all they need to do is climb around trees for few years eh? How is it possible that they are content to complain for 50 years and not do anything about it?
In my country in deciduous forests there can be often found birchs. Were barks of birches during industrial revolution in England also dark? Everything in the polluted areas was covered in soot. Black soot. Carbon black soot..The Peppered Moth quote: MartinV misrepresenting my argument writes: ... you as usually on such occasions emphasized "eternal truth" with "NO". Note that in Message 202 I said "You of course realize that in a polluted forest there is virtually NO light background area for typica moths to rest on, no matter what their 'preference' is in the matter?" (color, bold and underlined mine for emPHAsis). What I emphasis is what the data shows, what the observations show, what the evidence includes.
Are grasses, flowers, leaves, twigs, everything so dark in polluted forest as if somebody burned there cars tyres? Is such places even fit to live in? You tell me.http://faculty.tcc.fl.edu/hss/wallert/sswkr.html http://www.conservationtech.com/...5/England/Yorkshire-4.jpg http://www.conservationtech.com/...5/England/Yorkshire-8.jpg http://www.conservationtech.com/...4x5/England/Newcastle.jpg http://www.conservationtech.com/...ngland/St.-Cath-docks.jpg http://www.conservationtech.com/...s-4x5/England/Lancs-3.jpg http://www.conservationtech.com/...s-4x5/England/Lancs-7.jpg See How does Blake move from innocence to experience for some observations from this period:
quote: Why do you think we have anti-pollution laws now? Just to make things tough for industry?
Btw. is melanism observed only on peppered moths? What about Oak beauty moths and other species that according creationists:
Oak Beauty is the Pepper moth's closest relative in England and is a trunk rester, (unlike the Pepper moth) yet the melanic form may have increased from 33-36%, but was always in the minority although it lived in the same areas as the Pepper moth. Melanism is observed in many different species and can have several different causes, even among otherwise closely related species. Please look at the pictures of the two moths from your creationist website and tell me that the Oak Beauty looks exactly like the typica peppered moth. Oak Beauty: http://www.bible.ca/tracks/oak-beauty-biston-strataria.jpgTypica: http://www.bible.ca/...textbook-fraud-pepper-moth-typica.jpg Here's some other pictures of Biston strataria (search pages for "oak")http://www.northamptonshirewildlife.co.uk/...life/emoths.htm http://www.david.element.ukgateway.net/moths7.htm National Moth Night UK results from the Woodland Education Centre Introduction Here's a set of pictures showing variation in darknessAvailable Website Are they similar enough to the differences between Biston betularia typica and Biston betularia carbonaria to have comparable results due to polution? Given that all pictures of Oak Beauty, Biston Strataria, moths on google are significantly darker than Biston betularia typica and in fact are closer to carbonaria, the answer should be obvious. In case it isn't, it is because there is just not much difference between the two varieties of Biston stratari. This is a typical creationist slight of hand ploy, attempting to substitute a situation that does not apply for one that does. Enjoy. we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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RAZD Member (Idle past 1432 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Just to be clear ...
Btw. is melanism observed only on peppered moths? What about Oak beauty moths and other species that according creationists:
Oak Beauty is the Pepper moth's closest relative in England and is a trunk rester, (unlike the Pepper moth) yet the melanic form may have increased from 33-36%, but was always in the minority although it lived in the same areas as the Pepper moth.
I did not found refutation of this either on talkorigins or in Majerus articles. Is it hoax or a forgotten fact? "Creationist site on pepperd moth" So there is a clear, distinct and unambiguous shift in the proportions of populations between the varieties of the Oak Beauty Moth, Biston strataria, a related species that also inhabits the same general environment as the Peppered Moth, Biston betularia, ... ... even though the differences between dark and light forms is much less in the Oak Beauty Moth, Biston strataria, than in the Peppered Moth, Biston betularia, ... ... and this somehow demonstrates that
I'd like to see the logic behind those conclusions, seeing as they run counter to the evidence. Enjoy. we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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Akrid Inactive Member |
I’m not sure if this question fits here but I having this conversation with a creationist who said a animal has a set number of information in its DNA and it cant change species unless some scientist splices its DNA (and no doubt angering god in the process) He also seemed to think that because breeding dogs has not led to a new species that must mean dogs cant evolve.
All I knew to say is that we have been breeding dogs for only a short time compared to how long it takes for something to evolve that is so big. And also that breeding dogs with different dogs would only help them stay a dogs, it’s when a group gets isolated over a long time that they can evolve. However I wasn’t able to refute his claim that there’s a glass ceiling to how much a animal can evolve. And that DNA has a set number of information. I’m sure he’s wrong in his interpretation of how DNA works, but I'm not knowledgeable enough about it myself to finish the conversation. So thats when I decided I should join a forum where people know about this so I can learn stuff. Can sombody explain to me how DNA works when it evolves to make a new species? I figure it has somthing to do with Zygotes or somthing. Edited by Akrid, : No reason given. I am the only person god created, everyone else evolved
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AdminModulous Administrator Posts: 897 Joined: |
Unfortunately your question is off topic since this topic is centrally about natural selection and specifically regarding the peppered moth 'icon'.
There are, however, several threads on the subject here.
What is the mechanism that prevents microevolution to become macroevolution?Natural Limitation to Evolutionary Processes (2/14/05) Can random mutations cause an increase in information in the genome? and this thread is still open:
Allelic variants: Simple refutation of "Kinds" (and/or decreasing genetic diversity) Hopefully the answers can be found within. If you have further queries you can see if the question is on topic in any of the related open threads. Alternatively you can propose a new topic at the appropriate Proposed New Topics Enjoy your time here, and you might want to take a look at the links in my signature below to help get acquainted with things if you haven't done so already. New Members should start HERE to get an understanding of what makes great posts.
Comments on moderation procedures (or wish to respond to admin messages)? - Go to:
General discussion of moderation procedures Thread Reopen Requests Considerations of topic promotions from the "Proposed New Topics" forum Other useful links:
Forum Guidelines, Observations about Evolution and This could be interesting....
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Akrid Inactive Member |
Yes, I regretted posting in the peppered moth thread shortly after posting this, Im so used to other forums going way off topic, guess Im conditioned, I assumed this would have turned into a valility of evolution debate. Anyway thanks for the links I'll check out those threads.
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