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Author Topic:   Mimicry: Please help me understand how
Wounded King
Member (Idle past 2410 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 31 of 241 (414326)
08-03-2007 8:13 PM
Reply to: Message 29 by MartinV
08-03-2007 1:18 PM


Re: You aren't saying anything, just throwing up random references.
In such cases genes might have play no signifficant role.

Completely unsupported assertion based on ignorance. You seem once again to be unaware of the wealth of research in the field, in this case that which looks into the relationship between cold shock and heat shock and their effects on gene expression. Its strange since your reference directly discusses several examples.

Just for a record. "Genetic research" do not explain deep secrets of life sometimes.

http://8e.devbio.com/article.php?id=213

What? That link is to an explicit discussion of how genetic research can help explain 'deep secrets of life', if you have to be melodramatic about it.

You seem to have totally failed to pick up the point of the article, which is that the different phenotypes are the result of the interaction of the environment and the genotype.

Waddington's 'Genetic Assimilation' posits that since there is the capacity for variation on the basis of environmental factors then when there is a consistent environmental factor affecting the phenotype that phenotype will be selected for on the basis of the genetic complement which has the correct interaction with the environment to produce it. The alternative form of 'Genetic assimilation' is when the re is a genetic component for the development of an environmentally stimulated characteristic, the example given in the article you link to is callus development, elements in the pathway of that environmental response can be altered so the characteristic manifests in the absence of the environmental cue.

all you seem to have just done is illustrate my point, just giving references is pointless if you haven't read and understood them, and if reading that Gilbert article lead you to believe it was discussing the limits of developmental genetics then you have severe reading comprehension problems.

TTFN,

WK

P.S. That is a great article, one of the clearest explanations of genetic assimilation I have come across.


This message is a reply to:
 Message 29 by MartinV, posted 08-03-2007 1:18 PM MartinV has responded

Replies to this message:
 Message 32 by MartinV, posted 08-05-2007 3:18 PM Wounded King has responded

  
MartinV 
Suspended Member (Idle past 4144 days)
Posts: 502
From: Slovakia, Bratislava
Joined: 08-28-2006


Message 32 of 241 (414656)
08-05-2007 3:18 PM
Reply to: Message 31 by Wounded King
08-03-2007 8:13 PM


Re: You aren't saying anything, just throwing up random references.

all you seem to have just done is illustrate my point, just giving references is pointless if you haven't read and understood them, and if reading that Gilbert article lead you to believe it was discussing the limits of developmental genetics then you have severe reading comprehension problems.

Your responses are sometimes very instructive. Unfortunatelly it is not the case of your latest post. You focused your attention on "genetic assimilation" instead of "phenocopies" I wrote about. It is a little bit inaccurate to claim that the article supports your ideas. We are discussing non-darwinian explanation of phenomena of butterfly mimicry. As you may have noticed from the article - you have read it so carefully obviously, because you denigrated me - mainly three names were mentioned there:

1) Waddington
2) Schmalhausen
3) Goldschmidt

No one of them can be called a "neodarwinist". If you like I will quote you some opinion about neodarwinism from Waddington and Schmallhausen (Šmalgausen - even in Russian language if you like. His work is not very known, even though very interesting). Goldschmidt was a prominent saltationist, there is no doubt of it. So I don´t see reason for your enthusiam that those three great scientists with their experiments should support your neodarwinistic views.

I don't see a point why you has written so long about "genetic assimilation" and calluses. It has nohing to do with phenocopies I wrote about. If you have had read the article more carefully (instead of denigrating my reading abilites) you may had been noticed this sentence:

quote:

In this experiment, Waddington took advantage of an experimental phenomenon that is the converse of genetic assimilation: the phenocopy

You can read - "converse of genetic assimilation".


P.S. That is a great article, one of the clearest explanations of genetic assimilation I have come across.

I agree. But I was not writing about genetic assimilation. The article in no way support you neodarwinistic explanation of secrets of life - even if you think it does.

---

Btw. one would say that all genetic assimilation stuff is an interesting way how to apply neodarwinism to facts that support lamarckism. Such experiments would support more "inheritance of acquired traits".
Many scientists support such view before 2WW - but it was not the case of mentioned Goldschmidt - but after 2WW such experiments are almost not done anymore.
But this is another story.

Edited by MartinV, : No reason given.

Edited by MartinV, : thoughts about lamarckism added.


This message is a reply to:
 Message 31 by Wounded King, posted 08-03-2007 8:13 PM Wounded King has responded

Replies to this message:
 Message 33 by Wounded King, posted 08-05-2007 5:10 PM MartinV has not yet responded

  
Wounded King
Member (Idle past 2410 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 33 of 241 (414675)
08-05-2007 5:10 PM
Reply to: Message 32 by MartinV
08-05-2007 3:18 PM


Re: You aren't saying anything, just throwing up random references.
Just re-read the last paragraph.

Genetic assimilation can function by genetically fixing traits that had a phenotypic plasticity or it can genetically fix a phenocopy. For a phenocopy to be fixed, the population must be exposed to environmental conditions that repeatedly induce the phenocopy and there must be selective pressure such that the phenocopy is advantageous (produces higher fitness) in that environment (Rachootin and Thomson 1981). In this way, advantageous traits may be selected and incorporated into a population at a higher frequency that would be expected by random chance. As Waddington (1961) pointed out, a combination of orthodox Darwinism and orthodox embryology can give the results that look like the inheritance of acquired characteristics.

Clearly the fixation of the phenocopy is also considered a form of genetic assimilation, although it is 'converse' in its acquirement to the initial example, the callus which Waddington. I addressed the fixation of the phenocopy first in my post before the callus example.

One form is the change of the underlying genetic developmental mechanisms to stabilise a previously transitory environmental response, the other is the selection of a genetic background which maintains a particular phenotype, resembling the phenotype of some other species, in the presence of a constant environmental factor.

Neither of these phenomena does anything to undercut the importance of genetics, they simply emphasise that the genetics must be studied in the context of their interactions with an organisms environment, a perfectly neodarwinian approach.

So I don´t see reason for your enthusiam that those three great scientists with their experiments should support your neodarwinistic views.

Well I didn't say that, I said that the article doesn't present anything which doesn't support my neodarwinistic views, certainly not the experiments it discusses.

You can read - "converse of genetic assimilation".

One single phrase doesn't counter my point, that would actually require some reasoned argument. Why don't you try that instead of appealing to authority? I don't require Waddington, Goldschmidt and Schmalhausen to agree with me, I don't even require Darwin to agree with me. I have the benefit of a wealth of experimental evidence and genetic evidence which none of those scientists had so I can draw my own conclusions.

TTFN,

WK


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MartinV 
Suspended Member (Idle past 4144 days)
Posts: 502
From: Slovakia, Bratislava
Joined: 08-28-2006


Message 34 of 241 (417646)
08-23-2007 3:35 PM
Reply to: Message 24 by Modulous
08-03-2007 6:35 AM


Re: mimicry isn't the problem, then

Mimicry is more than just having similar colouration, of course, and I'd be surprised if you can find a good reason for some of the more elaborate mimics that did not require some reference to natural selection. I'd urge you to pick papers from after the discovery of genetics and the synthesis of same with other evolutionary mechanisms.

One would say the more resemblance to an unpalatable model the more survival advantage of a mimic. One would suppose that most of the mimics are perfect ones. This is obviously not the case. The most mimics are imperfect. Either we are living in the period of "evolution in action" or another force explaining mimicry should be reconsidered:

quote:

...consideration of the evolution of mimicry has been mostly confined to the evolution of good mimics, despite the obvious fact that most mimicry is of rather poor quality (Getty, 1985), and such poor mimicry is widespread in many Batesian mimetic systems (e.g. salticid spiders: Edmunds, 2000).

What a mess governs in darwinian explanation of the above mentioned fact! I have written in my previous thread that even if mimicry in insect realm is known more than 150 years there is no plausible explanation of it yet. There are many neodarwinian "armchair" theories that contradict each other essentailly. It is very bold to presume that neodarwinism has explanation of mimicry.

quote:

...More untested theories are not really a priority. Ideas about mimicry have been produced for at least 130 years, and the debris from them lie all around in the literature. Mimicry suffers more than most fields from a surfeit of armchair theorizing, often completely divorced from reality...

Check it yourselves in modern summary of the phenomenon of mimicry. Birds are sometimes not mislead by mimics (Dlusski experiments) as selectionists so boldly claim:

http://eprints.nottingham.ac.uk/archive/00000096/01/ImperfectMimicry.pdf


This message is a reply to:
 Message 24 by Modulous, posted 08-03-2007 6:35 AM Modulous has responded

Replies to this message:
 Message 35 by Shtop, posted 08-23-2007 7:22 PM MartinV has responded
 Message 39 by Dr Adequate, posted 08-24-2007 2:39 PM MartinV has responded
 Message 44 by Modulous, posted 08-27-2007 5:53 AM MartinV has not yet responded

  
Shtop
Junior Member (Idle past 642 days)
Posts: 30
Joined: 07-19-2007


Message 35 of 241 (417669)
08-23-2007 7:22 PM
Reply to: Message 34 by MartinV
08-23-2007 3:35 PM


Re: mimicry isn't the problem, then
MartinV writes:

Birds are sometimes not mislead by mimics

That is true. But sometimes, birds ARE mislead by mimics.

You seem to believe that darwinists think that mimicry provides immunity from predators. This is obviously not the case.

I have not studied the matter in any detail at all, so I am at great risk of oversimplifying this, but to me it seems very obvious.

I'm not sure exactly what your problem with mimicry is. Do you not believe it works? Of course there will be examples of mimicry not always protecting a specimen, but that doesn't mean it never works. Even if it only works 1% of the time, there will be positive selection pressure.


This message is a reply to:
 Message 34 by MartinV, posted 08-23-2007 3:35 PM MartinV has responded

Replies to this message:
 Message 36 by MartinV, posted 08-24-2007 12:21 AM Shtop has responded

  
MartinV 
Suspended Member (Idle past 4144 days)
Posts: 502
From: Slovakia, Bratislava
Joined: 08-28-2006


Message 36 of 241 (417750)
08-24-2007 12:21 AM
Reply to: Message 35 by Shtop
08-23-2007 7:22 PM


Re: mimicry isn't the problem, then
Perhaps you should read the above mentioned article. The article mentioned Franz Heikertinger only in flight and he deserves more I would say. Franz Heikertinger was an Austrian entomologist who refuted selection as source of mimicry.


I have not studied the matter in any detail at all, so I am at great risk of oversimplifying this, but to me it seems very obvious.

I agree. It seems to be obvious at the first glance. But the problem is that the matter is very complicated. I addressed many problems here and at closed thread Mimicry and neodarwinism

www.evcforum.net/cgi-bin/dm.cgi?action=msg&f=5&t=711&m=1 -->www.evcforum.net/cgi-bin/dm.cgi?action=msg&f=5&t=711&m=1">http://www.evcforum.net/cgi-bin/dm.cgi?action=msg&f=5&t=711&m=1


Even if it only works 1% of the time, there will be positive selection pressure.

So why imperfect mimics are not improved by natural selection even more? The only force working against "positive selection pressure" is "kin selection", something very dubious as you can see from the article.


This message is a reply to:
 Message 35 by Shtop, posted 08-23-2007 7:22 PM Shtop has responded

Replies to this message:
 Message 37 by Shtop, posted 08-24-2007 12:42 AM MartinV has not yet responded
 Message 38 by Dr Adequate, posted 08-24-2007 2:29 PM MartinV has not yet responded
 Message 45 by Doddy, posted 08-29-2007 12:38 AM MartinV has not yet responded

  
Shtop
Junior Member (Idle past 642 days)
Posts: 30
Joined: 07-19-2007


Message 37 of 241 (417753)
08-24-2007 12:42 AM
Reply to: Message 36 by MartinV
08-24-2007 12:21 AM


Re: mimicry isn't the problem, then
MartinV writes:

So why imperfect mimics are not improved by natural selection even more?

Well, a simple answer would be "because the selection pressure isn't big enough". But more to the point, what makes you say mimics aren't being improved? For all we know some species are well on their way to achieving perfect mimicry, they simply haven't got there yet.

I must admit I haven't had time to read the article properly yet. It's 42 pages so I will need time to sit down properly (plus I'm pretty unfamiliar with a lot of the jargon).


This message is a reply to:
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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006
Member Rating: 7.3


Message 38 of 241 (417776)
08-24-2007 2:29 PM
Reply to: Message 36 by MartinV
08-24-2007 12:21 AM


Re: mimicry isn't the problem, then
Perhaps you should read the above mentioned article. The article mentioned Franz Heikertinger only in flight and he deserves more I would say. Franz Heikertinger was an Austrian entomologist who refuted selection as source of mimicry.

But he cunningly disguised this so that no-one noticed it.


This message is a reply to:
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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006
Member Rating: 7.3


Message 39 of 241 (417778)
08-24-2007 2:39 PM
Reply to: Message 34 by MartinV
08-23-2007 3:35 PM


Re: mimicry isn't the problem, then
One would say the more resemblance to an unpalatable model the more survival advantage of a mimic. One would suppose that most of the mimics are perfect ones.

Why one "one" suppose that? Was "one" dropped on "one's" head when "one" was a child?

Either we are living in the period of "evolution in action" ...

As is, of course, the case.

What a mess governs in darwinian explanation of the above mentioned fact! I have written in my previous thread that even if mimicry in insect realm is known more than 150 years there is no plausible explanation of it yet. There are many neodarwinian "armchair" theories that contradict each other essentailly. It is very bold to presume that neodarwinism has explanation of mimicry.

Nice rhetoric, shame about the facts.

You remember facts? Those things real biologists like so much?

You know, biologists? The people who get out of their "armchairs" and study biology, as opposed to the people who sit on their lazy arses posting lies and gibberish on Internet forums.

Birds are sometimes not mislead by mimics (Dlusski experiments) as selectionists so boldly claim:

If you believe that "selectionists" claim that mimicry is always successful, then you appear to have mistaken a stupid, clumsy, ugly straw man of your own construction for "selectionists".

Which proves, I guess, that mimicry need not always be perfect. If you can mistake the idiotic garbage you've made up in your head for anything connected with mainstream biology, then obviously a resemblance need not be 100% ... or 50% ... or 1% ... in order to deceive a sufficiently myopic and dull-witted animal.


This message is a reply to:
 Message 34 by MartinV, posted 08-23-2007 3:35 PM MartinV has responded

Replies to this message:
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MartinV 
Suspended Member (Idle past 4144 days)
Posts: 502
From: Slovakia, Bratislava
Joined: 08-28-2006


Message 40 of 241 (417781)
08-24-2007 3:06 PM
Reply to: Message 39 by Dr Adequate
08-24-2007 2:39 PM


Re: mimicry isn't the problem, then

You know, biologists? The people who get out of their "armchairs" and study biology, as opposed to the people who sit on their lazy arses posting lies and gibberish on Internet forums.

I agree with you.

Edited by MartinV, : No reason given.


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MartinV 
Suspended Member (Idle past 4144 days)
Posts: 502
From: Slovakia, Bratislava
Joined: 08-28-2006


Message 41 of 241 (417788)
08-24-2007 3:49 PM


To administrator
I don't like the way Dr. Adequate is responding to my posts. Does he obey the EvC rules?

I suppose a man who describes insect predators as "myopic and dull-witted animal" which are probably responsible of stunning leaf-insect mimics that such a man does not have any right to call my reasoning " the idiotic garbage you've made up in your head".

Thank you for your response.


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Dr Adequate
Member
Posts: 16107
Joined: 07-20-2006
Member Rating: 7.3


Message 42 of 241 (417829)
08-24-2007 8:35 PM
Reply to: Message 41 by MartinV
08-24-2007 3:49 PM


Re: To administrator
I suppose a man who describes insect predators as "myopic and dull-witted animal" which are probably responsible of stunning leaf-insect mimics that such a man does not have any right to call my reasoning " the idiotic garbage you've made up in your head".


This message is a reply to:
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Adminnemooseus
Director
Posts: 3908
Joined: 09-26-2002


Message 43 of 241 (417837)
08-24-2007 9:26 PM
Reply to: Message 42 by Dr Adequate
08-24-2007 8:35 PM


Adminnemooseus opinion - Dr Adequate replies need improvement
Upon review, I would suggest that Dr Adequate tone down the sarcasm and improve the level of substance in his replies.

Any replies to this message should go to the "General discussion..." topic, link below. You may get a 24 hour suspension if you reply in this topic rather than that topic.

Also, to Martin: Other admins may think otherwise, but my opinion is that your complaint should also have gone to the "General discussion..." topic, complete with a link back to the message(s) in question (important!). That topic is for discussion of admin actions, but (IMO) it is also for discussion of admin inactions and to point possible problems out to the admins. Besides, there the complaint won't get buried and not noticed.

Adminnemooseus


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Please make it easy to tell you apart from the idiots. Source


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Modulous
Member (Idle past 420 days)
Posts: 7789
From: Manchester, UK
Joined: 05-01-2005


Message 44 of 241 (418254)
08-27-2007 5:53 AM
Reply to: Message 34 by MartinV
08-23-2007 3:35 PM


Re: mimicry isn't the problem, then
That does not seem to have any relevance to anything I said. You raise the point that most mimicry is not perfect which I agree with. That is nothing to do with the fact that mimicry is more than just having similar colouration and the challenge to explain other mimics with 'transformation rules' rather than natural selection.

This message is a reply to:
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Doddy
Member (Idle past 4225 days)
Posts: 563
From: Brisbane, Australia
Joined: 01-04-2007


Message 45 of 241 (418566)
08-29-2007 12:38 AM
Reply to: Message 36 by MartinV
08-24-2007 12:21 AM


Re: mimicry isn't the problem, then
MartinV writes:

So why imperfect mimics are not improved by natural selection even more?


Have you presented a specific example of this?


Help to inform the public - contribute to the EvoWiki today!

What do you mean "You can't prove a negative"? Have you searched the whole universe for proofs of a negative statement? No? How do you know that they don't exist then?!


This message is a reply to:
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