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MartinV  Suspended Member (Idle past 5859 days) Posts: 502 From: Slovakia, Bratislava Joined: |
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Author | Topic: Mimicry and neodarwinism | |||||||||||||||||||||||||||||||
MartinV  Suspended Member (Idle past 5859 days) Posts: 502 From: Slovakia, Bratislava Joined: |
WoundedKing writes:
You are correct, in Heliconius both males and females show mimetic patterning. An interesting paper has studied whether the mimetic patterns affect mate choice and it seems that by and large males prefer mates with the same mimietic patterning (Jiggins et al., 2004 ).
Thank for link. It shows, that red colour bands are sometimes so important, that they override appeal of their own race: "The broad red forewing band of the two ”postman’ races was generally attractive to all H. melpomene races and in some cases led to a higher probability that males would approach a pattern other than their own." Anyway I encounter again the proposition, that is not supported by any evidence (except "must have"): "...even though much, if not all of the diversity must have initially arisen through natural selection for mimicry." As we know, Heliconius is unpalatable, so the mimicry should be Mullerian. So I do not see any as so dramatic selection pressure that would have led to - as paper states - "... has evolved into a dramatic array of colour pattern races that mimic H. erato and other species (Turner, 1976; Brower, 1996)." Yet I found most interesting this sentence:"In the visually complex tropical rainforest environment, where conspecific individuals are inevitably rare and hard to encounter, it seems likely that the bright colour patterns of these butterflies would be used in finding mates." It completely contradicts to Suchantkes claim (link sended by RAZD): The vegetative lushness of the rainforest can present itself to the traveler as depressingly one-dimensional. The green leaf prevails-so much so that one can walk for hours without any change of scenery. "Finding a blossom provides very welcome relief for senses saturated by the endless monochrome of the lush foliage" (p. 100)." ( http://natureinstitute.org/pub/ic/ic7/rainforest.htm ) I am unable judge wihich opinion is more correct - I never visited rainforest btw - but we see, how differently rainforest can be percepted by two scientists and experts: "visually complex tropical rainforest" vs "An Intense Monotony of Green". On this perception they based further reflections and therefore they may - in case of mimicry - come to different conclusions as to the nature of selective pressure (to look inconspicuos in green vs. visually complex environment is not the same.)
There almost certainly are different selective pressures on the males in those different locations, even from within the population itself alone in terms of mating choice.
I do not see point. Why is selective pressure on butterfly males of Papilio d. in Africa much more less than on males of Heliconius in South America? Do birds in Africa prefer eating only females of Papilio dardanus, so the males are not under selective pressure? On the other hand we know that Heliconius is unpalatable. I do not see reason, why Heliconius males should always look like their females, if eatable males of palatable Papilio d. do not look like their cryptic females and even do not mimics anybody to protect themselves.
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AdminNWR Inactive Member |
In other words you admit you have no integrity. None. You just demonstrated that you are not interested in the truth.
Comment on the contents of what is posted. Avoid comments on the person. To comment on moderation procedures or respond to admin messages:
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jar Member (Idle past 424 days) Posts: 34026 From: Texas!! Joined: |
One question which I hope does not take us too far astray.
In many species of insects, IIRC, the sole function of the adult stage is to lay eggs. Again, IIRC, many of the adult stage critters do not even have the equipment needed to feed, Luna moths and Mayflies come to mind. In these critters the sole purpose of the male is to found by a female so he can fertilize eggs, the male needs to be found. The female on the otherhand must live long enough to find a place, or in many cases several places, to lay eggs. Of necessity this means staying in one place for a considerable period of time. It would seem to me that anything that would increase the likelyhood of not being eaten while laying eggs would provide an advantage, whether it is protective camouflage or mimicking some non-edible critter, and so those who are least noticeable would have the highest probability of founding the next generations. Is that at all reasonable? Aslan is not a Tame Lion
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Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
As we know, Heliconius is unpalatable, so the mimicry should be Mullerian. So I do not see any as so dramatic selection pressure that would have led to - as paper states - "... has evolved into a dramatic array of colour pattern races that mimic H. erato and other species (Turner, 1976; Brower, 1996)." Even if a species is itself unpalatable it may still gain a benefit from mimicry of a more unpalatable species.
I am unable judge wihich opinion is more correct - I never visited rainforest btw - but we see, how differently rainforest can be percepted by two scientists and experts: "visually complex tropical rainforest" vs "An Intense Monotony of Green". I don't think these two are neccessarily contradictory. An environment which is monotonous in terms of colour may still be visually complex in terms of form with multiple layers of overlapping foliage. You are assuming that visually complex means multi-coloured but I'm not sure that that neccessarily follows. Also lets not forget that the point of the mimicry in these cases is to look conspicuous rather than inconspicuous, this is not leaf mimicry after all but mimicry of an aposematic signal. TTFN, WK
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MartinV  Suspended Member (Idle past 5859 days) Posts: 502 From: Slovakia, Bratislava Joined: |
jar writes:
...and so those who are least noticeable would have the highest probability of founding the next generations.
Maybe you can find some opposite information to support your view - I would like read it - but according Professor of Chemical Ecology at Cornell University Thomas Eisner: 1) "Butterflies are the most conspicuous of insects...they are recognizable for what they are from further away than any other insects." 2) "The fact is that butterflies are not at all easy to catch. They are erratic fliers whose aerial trajectory is all but linear." 3) "but as regards insectivorous birds as a whole, the evidence indicates that most simply don’t go after butterflies." Even though Eisner added some mandatory darwinian explanations of the fact, that butterflies are most conspicuous insects and that birds do not go after butterflies, it is evident - if Eisner is right in above mentioned point 1 and 3 - that puzzle of mimicry of Papilio dardanus remains not only intact but your selectionistic explanations seem in the light of these new facts even more shaky. I only do not agree that butterflies are not easy to catch - it seems to me, that to catch a flyis much more diffcult, but swallows do not have any problem to catch them. So the reason why birds do not massively eat butterflies is maybe another. Scales: On the Wings of Butterflies and Moths | VQR Online
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New Cat's Eye Inactive Member |
I was gonna get involved in this thread but had some questions for you first in Message 15. If you could answer those, even though they might be OT, I'd be more inclined to discuss this with you. I haven't read the rest of the thread yet though.
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MartinV  Suspended Member (Idle past 5859 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Maybe you should read some of my responses. I suppose, that behind evolution are other forces that rm/ns and that evolution is somehow directed by internal creative forces, preprogrammed or something like that. Butterflies mimicry and realm of insects put before us puzzles, that can be hardly explained by RM/NS mechanism except one believe strongly in darwinism.
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New Cat's Eye Inactive Member |
Butterflies mimicry and realm of insects put before us puzzles, that can be hardly explained by RM/NS mechanism except one believe strongly in darwinism. emphasis added Well, at least there is an explanation. What is your explanation? Just point me to the post if you've already wrte it. All in all, it still seems like you are arguing from incredulity. Do you think that a phenomenon that is a 'problem' for neodarwinism somehow discredits everything it claims? Do you have an alternative explanation for the phenomenon? Why do you have a problem with neodarwinism? (other than the mimicry thing) Do you realize that the difficulty to believe something has no affect on its truth value? Do you realize that you are arguing from incredulity? Other than these questions I was wondering about, you seem to have done a decent job of exemplifying a phenomenon that is difficult to explain with neodarwinism. IMHO, that doesn't count as any falsification, just an example where more effort could be placed. Science fails to recognize the single most potent element of human existence. Letting the reigns go to the unfolding is faith, faith, faith, faith. Science has failed our world. Science has failed our Mother Earth. -System of a Down, "Science"
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MartinV  Suspended Member (Idle past 5859 days) Posts: 502 From: Slovakia, Bratislava Joined: |
Do you think that a phenomenon that is a 'problem' for neodarwinism somehow discredits everything it claims?
Yes. I suppose, that baffling cases of Melpomene and Papilio dardanus invalidate neodarwinistic explanation, that everything in animal world is a result of blind chance cultivated by natural selection.
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New Cat's Eye Inactive Member |
So you're not going to offer a different explanation, you're just going to say that the current explanation does not convince you, so therefore it must be wrong. Unfornunately, for you, that is a logical fallacy and you're convincing no-one.
Finding one example of something that is difficult to explain with a theory does not invalidate the rest of the theory's explanations.
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Muhd Inactive Member |
For those of us who have not been indoctrinated into believing the theory, it is just one more reason not to believe.
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jar Member (Idle past 424 days) Posts: 34026 From: Texas!! Joined: |
1) "Butterflies are the most conspicuous of insects...they are recognizable for what they are from further away than any other insects." Well, no telling what was in the ellipsis, BUT, if true (and dragonflies might be equally is not even more recognizable), that simply supports the scenario I outlined.
2) "The fact is that butterflies are not at all easy to catch. They are erratic fliers whose aerial trajectory is all but linear." Again, that simply supports the scenario I postulated. When laying eggs they are not moving.
3) "but as regards insectivorous birds as a whole, the evidence indicates that most simply don’t go after butterflies." All it takes is one. I have personally watched Mockingbirds catch butterflies as well as Kiskadees. Aslan is not a Tame Lion
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subbie Member (Idle past 1285 days) Posts: 3509 Joined: |
Finding one example of something that is difficult to explain with a theory does not invalidate the rest of the theory's explanations. It's a very curious approach: evaluate the worth of a theory by looking only at its difficulties. I daresay that no theory could stand up to that kind of scrutiny. Every vital, valuable scientific discipline has unexplained questions. If a creo really wants to attack evolution, try to show how its successes aren't really successes. The best way to do that would be to show how creationism better explains the things that evolution does explain. I shall now sit back and listen to the deafeningly silent response to this challenge. Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
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New Cat's Eye Inactive Member |
For those of us who have not been indoctrinated into believing the theory, it is just one more reason not to believe. You shouldn't need reasons to not believe. Not believing should be the default position until the theory is convincing. Look at all the explanations that the theory does offer and judge it on those, not just the areas where there is still difficulties. If you judge the theory only by the difficult areas, then I'd say you have a motive before you began. If you have a motive and start with finding reasons to not believe, then you're not being honest with yourself. But you can do whatever you want, and be as honest as you want, especially with yourself. Just don't push your own self-dishonesty onto other people and we'll all live happily ever after.
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Brad McFall Member (Idle past 5063 days) Posts: 3428 From: Ithaca,NY, USA Joined: |
quote: It is one thing to critize "darwinism" and another to say what is supposed to remain AFTER the critic has a few beers or read G. de Beer. Gould for instance relies on "branching" topology during speciation without regard to a specfic form. He even, at last insists for tests of ancestral formations surviving-through-his specific criticism but this can not be discriminated (today)from the notion of kinds Biblically. Davison, because he rejected a direct influence of the environment on the beings being created through this kind of point set uped controversy, is not close to Eisner's 70s writing (I tried to find it on -ine but failed) that systematic use of poplation genetics (natural selection in the wild etc.) is not going to yield a lot of data to biology(potentially "missing" data (left out) in Gould's parlance). So both Gould and Eisner critcize "darwinism" but turn out doing different kinds of research. Eisner stuck to elucidating actual chemicals involved in entomology(he cared very much for the biology of insects (personal observation) quote: )while Gould attempted to erect a metathematics in which futher growth of biological thought could correlate allometrically. Davison seemed to resist, for perfectly comprehensible creationist predilections I should add, attempts to extend the theoretical space on close observational terms of his critique in>to areas some of us on EvC thought it might reply through, though. And so it is hard to understand, for me at least, how to differentiate simple qualms about mimicry and general vs particular dissatisfaction with standard evolutionary theory of the 60s.
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