This is PRATT, and the solution is obvious. Copy a function, tinker with one copy so the original function is maintained. Dawkin’s Weasel was an example of genetic search and was not programmed for duplication - BUT biology does this very neatly.
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Love the 90s vibe! No I don’t want to fight and you are right to call me out for my rudeness. Much of what you wrote is plainly wrong (about fitness landscapes most notably), so I do think I am clearly justified in suggesting that you don’t read the literature. I hope you might accept my apology for gruffness. I haven’t changed my mind about whether you know what you’re talking about.
Better than that, here’s one I wrote:
https://sfmatheson.blogspot.com/2009/09/weasels-clouds-and-biomorphs-part-i.html
My article includes data on how often the Weasel program has been cited or discussed in the scientific literature. I haven’t updated those data but I would on request.
EDIT: the data I include are not about the “scientific literature” but about a website. I will atone for this appalling error by doing some quick research on the extent to which the Weasel program has been mentioned or discussed in the literature, and compare that to the Biomorphs program.
the initial definition concerned a property of a system. AFIAK at least for the bacterial flagellum Minnich showed that that’s correct.
Behe modified his argument quite a lot in his later books, but that’s another issue.
please define ‘darwinian’. I mentioned the definition of Ernst Mayr. Do you know it?
I said in my posting that there are two issues in evolution: adaptation and novelties. Further on this line is the difference between pattern and process. You mentioned a pattern. The more interesting question concerns the processes. Even if you see evolution you don’t know how it works. Is it possible without design? some people ask and that’s not easy to decide.
If a system has no function before all its components are in place, selection never ‘sees’ an improvement.
That’s an interesting question. I’ve read through quite a lot of evolutionary literature ever since Darwin, specialising in heterodoxies. There are concepts like IC (e.g. correlation of parts, interlocking complexity), but not at the level Behe is discussing.
If you’re interested I can mail you the source code or an exe-file demonstrating it. I modified the program only in that sense that some letters are only selectable if they come together. You see that the regions before and after that IC-part are found quickly by the program, but the IC-part isn’t.
That modification shows, what cumulative selection can do, but also what it can’t.
I’m not so sure. Living in Germany the situation is quite different from the US. The best source conderning the difference between YEC and ID I know, is
Ross, M.R. (2005) ‘Who Believes What? Clearing up Confusion over Intelligent Design and Young-Earth Creationism’ Journal of Geoscience Education 53 (3):319-323
or, more popular,
Ross, M.R.; Nelson, P.A. (2006) ‘A Taxonomy of Teleology: Phillip Johnson, the Intelligent Design Community and Young-Earth Creationism’ in: Dembski, W.A.; (ed.) ‘Darwin’s Nemesis. Phillip Johnson and the Intelligent Design Movement’ Leicester, Inter-Varsity Press S. 261-275
Ross and Nelson are YEC, but the arguments in these articles are convincing.
I’ve published quite some articles about the difference between YEC and ID and I’m quite sure that I know the difference between these positions. If you can read German I can send you an article I wrote showing what’s new about Behe compared with Paley.
Natural selection acting on heritable variation. And I think you need to adjust your quoting a bit.
The problems are that 1) the conclusion is often taken as the definition and 2) the conclusion doesn’t follow from the definition of the property.
What makes you think that this is not compatible with IC?
Can you support this assertion?
No, but please do explain, or at least cite something adequately.
You contradict yourself. Scaffolding is quite compatible with a Darwinian mechanism, as are several other ways to arrive at IC by selection.
This assumes, again, that evolution must occur by the sequential addition of invariant parts. But that’s not at all how it works. I think you have a basic misunderstanding of the data.
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Thanks for pointing this out.
I have been looking into this program very closely and thought that I might be able to contribute something that hasn’t been discussed here yet.
But no problem, if that’s not what you want, I’ll refrain from doing so.
you know how Behe reacts to that?
Yepp. But Dawkins never mentioned duplication and his program was intended do demonstrate what he wrote in the first lines in his The Blind Watchmaker.
If you agree that his mechanism without duplication doesn’t work, okay.
The real question is, how that happens in nature (biology isn’t an agent). You know, how genes get duplicated, there are gene familes, but how to get from a duplicated gene to a new function is interesting.
Do you agree that duplication is a ‘pattern’, no ‘process’?
no problem.
Thank you for the link. I visited your website quite some times before and found it very interesting.
I’ll read your article and write some comments about it later.
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This looks like deliberate evasion. Try again. What do you mean by this:
What exactly is Mayr supposed to be defining? Why doubt that there are indirect Darwinian routes when they seem to be inevitable?
Hence indirect routes.
Change of function would be one example and that’s hardly new. And of course the parts themselves can change. A part that was only useful can become essential.
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AND maybe you can, but it wouldn’t hurt to look at what has gone before. You might discover something you hadn’t considered before.
PS: I’m a moderator, not the Thought Police. 
Who cares how Behe reacts - it is not relevant.
How do evolutionary biologists react?
The Blind Watchmaker was not a textbook on genetic algorithms. WEASEL was a demonstration of a basic principle, and it works for that purpose. If you think Dawkin’s had some other purpose, then please state what you think that is.
It is very interesting, and there are whole fields of study dedicated to how that happens in nature. I’m not a biologist, but a mutation that duplicates part of the genetic code isn’t hard to understand. Once duplicates exist, each may accumulate new mutations independently. If the function is essential then one copy will tend to be preserved (conserved). Surely you know this already?
I would not agree to either without further details on what you mean.
Oh dear. Perhaps you should inform yourself on the matter. Dawkins wrote the “weasel” only to illustrate that cumulative selection was much better than random guessing. It wasn’t mean to show anything more. It’s all in The Blind Watchmaker
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I’m quite informed about that. Quite a lot of material for teachers used that program. I was taught the reason behind it in the 1970s studying biology, even before Dawkins wrote his book.
I got interested in that program many, many years later in connection with IC because it made a problem explicit.
Of course I know that there are a lot more and more elaborate models in evolutionary biology, but there are some problems never solved ever since Darwin.
I’m not arguing for Design, I’m just analyzing controversies.
What is that argument, really? It’s not clear.
I don’t see why natural selection acting to preserve variation that improves fitness should be thought incapable of producing an IC system. The function of the system can be different throughout it’s evolution, essentially involving steps of novel functions many times throughout.
So the simplest system performs function A which enhances fitness. Next step is slightly more complex, and performs function B which enhances fitness further. Final step is more complex still and performs function C, which also enhances fitness. C can’t function without the parts added in steps A and B, so the system is IC and yet it evolved by a textbook Darwinian mechanism.
What is wrong with this scenario?
So you wrote:
Knowing that it wasn’t true? That Dawkins never intended the “weasel” to demonstrate any more than it did?
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the program demonstrated two things: what cumulative selection can do, and why IC is a problem for that.
Does ist matter what Dawkins intended? What did Dawkins intend with his biomorph program(s)? What’s the difference between them and the Weasel-program?
What do you want to discuss: Dawkins’s intention or what I intend?
I responded to questions oder wanted to argue. But yes, I’ll do my homework.
Hmmm, there is an argument from Behe (e.g. the IC-argument), and there are replies from naturalists or non-interventionists. Isn’t it important how Behe responds?
As I wrote, it should show that cumulative selection is working. Not more, but not less.
But it is also a model to show the problem that IC is for that mechanism.
Of course. And I’ve studied biology and did quite a lot of work regarding history of evolutionary biology, specializing in heterodoxies. Because of that I’m not too impressed by arguments like “most evolutionary biologists …”. Tides are sometimes changing. I remembered in my posting that the Extended Synthesis unearthed theories from times before the Modern Synthesis was achieved in the 1940s and were regarded als refuted.
A ‘pattern’ is what you’re seeing in nature, e.g. fossils in different strata, homologies (morphological,genetical or whatever) and so on. Most ‘proofs of evlolution’ belong to this category. A ‘process’ is a theory explaining mechanistically how these pattern are generated.
The main issue between ID and evolutionary biology concerns ‘processes’. Don’t forget that e.g. Behe accepts all of evolutionary biology regarding patterns, even that man and apes have common ancestors.
This is false. If any program was written (by Dawkins) for this purpose, it is the Biomorphs program, which has been mentioned/cited in recent work (see esp. work from Ard Louis’ group, which I discussed previously on the forum). I respectfully suggest that you read (or re-read) The Blind Watchmaker.
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Sure, but we can just dispute the assumption (which is all it is) that the system has no function if all it’s parts are not in place.
In many cases where we look at the individual parts, or partial structures, we can see they are derived from other systems or functions, or how the partial structure would perform a useful function.
By partial versions of the “final” structure still performing useful functions. Those functions might be different from the final one, so you’re not selecting for the same function to just improve by tiny increments, instead you’re just selecting for “any novel change that increases fitness.”
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I’ve seen various responses. All of them terrible. Which one do you have in mind?
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how can fitness of a non-functioning system be improved?
Of course, but that is non-darwinian. Even Darwin proposed a change of function, but it didn’t fit well into his theory. The concept was elaborated by Dohrn in
Dohrn, A. (1875) ‘Der Ursprung der Wirbeltiere und das Princip des Functionswechsels’ Leipzig, kein Eintrag
The problem is that it’s easy to evolve a system if there is a gradient of function (e.g. an eye from a light-sensitive spot along a gradient of visial acuity). But if you have to change that function, pure chance (okay, there are concepts …) must do what selection cannot.
This model was proposed by Orr in the Boston Review.
Orr, H.A. (1996/97) ‘Darwin v. Intelligent Design (Again). The latest attack on evolution is cleverly argued, biologically informed - and wrong’ URL: http://bostonreview.net/archives/BR21.6/orr.html, letzter Zugriff: 14.05.2008
Behe responded in some articles, e.g.
Behe, M.J. (1997) ‘Michael Behe’s Response to Boston Review Critics’ URL: http://www.discovery.org/scripts/viewDB/index.php?command=view&id=47&program=CSC%20Responses&printerFriendly=true, letzter Zugriff: 27.09.2008
or
Behe, M.J. (2001) ‘Reply to My Critics: A Response to Reviews of Darwin’s Black Box: The Biochemical Challenge to Evolution’ Biology and Philosophy 16 (5):685-709
The main issue is the first sentence:
If A is the IC-Function there is no function A. If it has that function even in a minimal degree, it isn’t IC. If it has another function, it’s an indirect path.
If I see it correctly, even
Thornhill, R.H.; Ussery, D.W. (2000) ‘A classification of possible routes of Darwinian evolution’ URL: http://www.cbs.dtu.dk/~dave/JTB.html, letzter Zugriff: 21.02.2014
concede that IC-systems are not evolvable by a direct darwinian pathway. But there are indirect ones …
Behe wants to see very detailed models for these pathways. As far as I know that would be the easiest way to refute him, I’m not sure if these exist. But Behe has changed his argumentation in his later books, IC isn’t of much importance for him now.