VMartin
Posts: 525
Joined: Nov. 2006
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Hi folks. I am much impressed by your linguistic analysis of my poor english. Do you work like level-experts sorting pupils in Berlitz-school or something like that? Its big pleasure to discuss some mimicry issues with linguistic experts too.
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Why can't a gene cluster, or a single master regulator be changed? Especially with interspecies breeding, predation, sexual pressure on mate selection, are we suprized complex traits emerge?
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Yes. Might be that modern neordarwinsts are not surprized but when the case of Papilio Dardanus was first published in 1868 it was shock to the scientific world.
I consider the case as something that can be hardly explained by random mutation and selection.
First I would like to notice again that male-like, mimetic and non-mimetic female morphs of P.dardanus live in the same region and make up the same race. You would probably agree that colors of mimetic trophonius and non- mimetic leighi are very different (even if they belong to the same group hippocoon according Nijhout.)But not only that, there are other forms in mentioned race (Shepard and Clarke 1959):
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This race (cenea) inhabits South Africa, northwards to Delagoa Bay. The males are monomorphic, yellow, tailed and nonmimetic as they are wherever the species is found (Figure 1). The female forms that have been studied by us are the nonmimetic f. leighi, f. natalica and f. salaami and the mimics f. hippocoonides, f. cenea, f, trophonius (Figures 2-7) and a modification of f. trophonius in which the large apical spot on the forewings is buff and not the normal white (for a description of the forms, their models and their distribution see FORD19 36 and CLARKaEnd SHEPPAR1D9 59a).
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Together with mentioned case in my previous post where male-like females make up 80% of population and mimetic females only 20% question stands like: How is it possible that mimetic form are not prevalent? If the mimic do not thrive better than non-mimic what forces had driven evolution of such a form? It was hardly selection due predation - predation on mimetic and non-mimetic forms seem to be same otherwise one of the form would die out. We see similar process in neodarwinistic icon peppered moths - there according scientists only small selective advantage of melanica vs.
typica would led in only few decades to their clear prevalence.
Explanation of mimicry that neodarwinists offer are that of batesian/mullerian mimicry. It should led to greater protection of mimetic form and subsequent survival.
As we clearly see this is not the case - non-mimetic forms thrive as well - even better!
Sole mutation of regulatory genes as you and some other people here proposed is without selection inconcievable - how it happens that random mutation of "master gene" alone would lead to the same wing patterns and colors distribution as exist in unpalatable species?
Btw. here comes neodarwinistic dialectic - first step was due "genetic effect of large magnitude" and than follow tuning of mimicry to the model via small mutations. You generally cannot argue with such a dialectic - neodarwinist would shift border between tham according situation.
Yet that such process would led to 14 different morphs in one species most of which are mimetic without any selective advantage over non-mimetic morphs - I would say that also hard-cored neodarwinist should be little surprised - expect he is the linguist-polyglot of course.
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Summary: on my opinion chance and selection cannot play a role in the case of polymorphism of P.dardanus (Mocker Swallowtail). It is in accordance with professor John Davison claim that evolution was never driven by such forces.
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I could not answer, but should maintain my ground.-
Charles Darwin
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