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Author Topic:   Eye Evolution: Comments about the Great Debate
Zhimbo
Member (Idle past 6012 days)
Posts: 571
From: New Hampshire, USA
Joined: 07-28-2001


Message 16 of 30 (67935)
11-20-2003 9:28 AM
Reply to: Message 14 by Dr Jack
11-20-2003 5:04 AM


Well, on my monitor, green was hard to read, blue was, well, you know...and it was late and I didn't wanna keep messin' with the colors.
I don't intend to use colored text again, so rest easy.
In the meantime, a good trick is to use your mouse to select the offending text. For me, at least, it turns white on a dark-blue background; your settings may vary.
[This message has been edited by Zhimbo, 11-20-2003]

This message is a reply to:
 Message 14 by Dr Jack, posted 11-20-2003 5:04 AM Dr Jack has not replied

  
Loudmouth
Inactive Member


Message 17 of 30 (68068)
11-20-2003 5:17 PM


Maybe I should start taking bets on how Joralex will respond.
Choice 1:
It is your own metaphysical assumptions that keeps you from seeing how nature was created.
Choice 2:
No response. You guys are unfair and will never understand anything about reality.
I don't think we will se a detailed biologically based response, just from past behavior.

  
MrHambre
Member (Idle past 1393 days)
Posts: 1495
From: Framingham, MA, USA
Joined: 06-23-2003


Message 18 of 30 (68509)
11-22-2003 12:33 AM


No offense to Zhimbo, whose first post was superb, but this is not a fair fight. Joralex is just a hopeless bastard. I love this line:
quote:
Note also that "seeing" isn't merely receiving an electromagnetic signal since, if this were so, then rocks also "see".
Anybody still puzzling over this rhetorical question?
quote:
For instance, I hand a blue crab a fully-formed human eyeball - is it of any use to the blue crab?
If the subject of the debate weren't in the thread title, I'd wonder:
quote:
Haeckel used the words, "simple little lump of albuminous combination of carbon" to describe "simple" life. Of course, this was before we had learned of the immense complexity that is in a cell - any cell.
quote:
The fact remains that without ALL of the 40 proteins present and in their precise structure, their is no flagellum - period!
quote:
Tell me : is it possible that life was planted here on Earth by aliens from another galaxy roughly 600 million years ago?
And then, after Percy had made it clear Joralex has another whole week to come up with a decent reply, the J-man apologizes for being pressed for time during the formulation of the response. Good strategy.
------------------
The dark nursery of evolution is very dark indeed.
Brad McFall

Replies to this message:
 Message 19 by NosyNed, posted 11-22-2003 1:01 AM MrHambre has replied

  
NosyNed
Member
Posts: 8996
From: Canada
Joined: 04-04-2003


Message 19 of 30 (68514)
11-22-2003 1:01 AM
Reply to: Message 18 by MrHambre
11-22-2003 12:33 AM


I disagree with you a bit MrH.
Joralex did makes some points. He didn't do it very well, he did it a bit 'thinly' and he did it over and over but there is a point.
For example:
Anybody still puzzling over this rhetorical question?
quote:
For instance, I hand a blue crab a fully-formed human eyeball - is it of any use to the blue crab?
I think the point he is making (poorly) is that it takes more than the eye. It takes the complete chain of structures.
I have to agree with you that a lot of what he posted was a waste of time. And the rocks "seeing" bit is another poor attempt to make his point.
I do think however, that he has a point.
There does need to be enough structure to connect the capture of photons to some useful action.
I think he missed the point that Zhimbo is making though. He has missed that almost all of the structure can be there first and separately from the "seeing" part. But that is partly Zhimbo's fault (at this point). He hasn't made that clear enough yet. But then I guess he didn't think Joralex would miss it so badly.
We'll see what is next.

This message is a reply to:
 Message 18 by MrHambre, posted 11-22-2003 12:33 AM MrHambre has replied

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MrHambre
Member (Idle past 1393 days)
Posts: 1495
From: Framingham, MA, USA
Joined: 06-23-2003


Message 20 of 30 (68517)
11-22-2003 1:25 AM
Reply to: Message 19 by NosyNed
11-22-2003 1:01 AM


Ned,
I think you answered your own questions about the J-man's argument. They're not talking about the evolution of the nervous system or brain. Zhimbo doesn't have to propose a developmental pathway for anything except an organ of sight, and Joralex seems to find it unfair that the evolution of the entire neural network doesn't have to be explained in detail.
I admit Joralex could get some mileage out of his assertion that a series of eyes in increasing order of complexity don't necessarily constitute a developmental pathway. At least that's relevant to the topic.
------------------
The dark nursery of evolution is very dark indeed.
Brad McFall

This message is a reply to:
 Message 19 by NosyNed, posted 11-22-2003 1:01 AM NosyNed has not replied

Replies to this message:
 Message 21 by Chiroptera, posted 11-22-2003 1:08 PM MrHambre has not replied

  
Chiroptera
Inactive Member


Message 21 of 30 (68541)
11-22-2003 1:08 PM
Reply to: Message 20 by MrHambre
11-22-2003 1:25 AM


quote:
Zhimbo doesn't have to propose a developmental pathway for anything except an organ of sight, and Joralex seems to find it unfair that the evolution of the entire neural network doesn't have to be explained in detail.
I will agree with NosyNed that it is necessary, in order to adequately explain the evolution of the eye one must show that the "eye" is useful, which means that there must be some reasonable mechanism to allow "sight" to affect the behaviour of the organism.
Zhimbo did this in his first post:
Consider a small, transparent, aquatic, motile organism. A molecule that is in a pathway that affects motility become photosensitive due to a mutation. (Alternatively, it may become sensitive to a photosensitive chemical already present in the cellular environment). Thus, when in light, the motility biochemical pathway changes. In the presence of light, the organism either 1) slows down or 2) speeds up. If the organism photosynthesizes, then option 1 is adaptive, as the organism now tends to stay in light and move out of shadow. Alternatively, if the organism, say, filter feeds but is more visible to predators in light, then option 2 is adaptive. The organism now tends to stay in shadow and move out of light.
A wonderful scenario, in my atheist/humanist/conspiratorial biased opinion. I thought that Joralex merely missed the point and I was going to criticize your post, MrHambre, until I read Joralex's reply a bit more carefully and saw that Joralex dismissed Zhimbo's scenario with:
Consider my POINT 1 and think about the complexity contained therein....I don't disagree at all but you are hand-waving over a huge amount of complexity. The devil is in the details and you're skipping over most of them.
So now I agree with MrHambre. Joralex seems that he/she is going to just dismiss this example with no real argument. The reference to Point 1 seemed to concern a much more complex visual system than Zhimbo was talking about in his initial example - the topic here is supposed to be: "How can a visual system evolve?" Zhimbo needs to come up with a plausible candidate for a first system. The complexity mentioned in "point 1" is not relevant for this example - it may be relevant if the discussion moves to discuss how this initial first system may evolve into the more complex systems, but is not relevant here.

This message is a reply to:
 Message 20 by MrHambre, posted 11-22-2003 1:25 AM MrHambre has not replied

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Zhimbo
Member (Idle past 6012 days)
Posts: 571
From: New Hampshire, USA
Joined: 07-28-2001


Message 22 of 30 (70786)
12-03-2003 1:23 PM


Just a "bump" to make sure my latest reply didn't get overlooked...Percy has spoiled me with his usual rapid response/summary, so I'm squeaking a little. (You know, "squeaky wheel" and all that).

Replies to this message:
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Loudmouth
Inactive Member


Message 23 of 30 (70795)
12-03-2003 2:02 PM
Reply to: Message 21 by Chiroptera
11-22-2003 1:08 PM


Joralex seems that he/she is going to just dismiss this example with no real argument. The reference to Point 1 seemed to concern a much more complex visual system than Zhimbo was talking about in his initial example - the topic here is supposed to be: "How can a visual system evolve?" Zhimbo needs to come up with a plausible candidate for a first system. The complexity mentioned in "point 1" is not relevant for this example - it may be relevant if the discussion moves to discuss how this initial first system may evolve into the more complex systems, but is not relevant here.
This may cause a little topic drift, but how would a sunflower's ability to track the sun fit into this. Their ability doesn't seem to rely on a nervous system or a specific organ for sight. The only problem is that this system obviously did not evolve into the eyesight we see in animals.

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Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 24 of 30 (70824)
12-03-2003 3:37 PM
Reply to: Message 22 by Zhimbo
12-03-2003 1:23 PM


I haven't forgotten - I need to put together a larger block of time than I've had lately. Probably will review it by tomorrow night, though. Sorry for the delay, too much going on. Maybe Joralex can take good advantage of the extra time.
--Percy

This message is a reply to:
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FliesOnly
Member (Idle past 4145 days)
Posts: 797
From: Michigan
Joined: 12-01-2003


Message 25 of 30 (71045)
12-04-2003 5:47 PM


I am new to this forum, so please forgive me if I make any glaring errors in my posting.
After reading many of the the threads that deal primarily with the global flood and those that question the validity of creationism as a science, I eventually found my way to "The Great Debate".
In his latest response, Joralex makes the following statement:
But the most serious response that I have against your argument is that addition or subtraction of parts is only one aspect of a complex system. What I mean is that, for example, suppose I were to hand you all of the individual parts that make up a Space Shuttle. Okay, now hand me an operational Space Shuttle.
You see, even if all of the parts are present, they require a very specified assembly for functionality. Failure of just one of those parts may render the entire system 'non-functional' (as we have tragically witnessed).
I fail to see why this falsifies the evolution of the eye. Actually, I think it supports what Zhimbo was trying to say...kinda. Let me see if I can adequately explain what I mean. In the first have of the above quote, Joralex informs us that we're trying to build a functional space shuttle and then gives us all the parts (what a nice guy). Then in the second half of the quote he seems to imply that we cannot possibly assemble an actual space shuttle because of its complexity. Ok, first off, we all know that evolution doesn't work that way. Evolution has no goal and cannot predict future novel contingencies, but hear me out. I'm saying that if you give me all the parts needed to assemble a space shuttle and enough time...I will give you back a functioning space shuttle.
Can I do this because I am a brilliant aerospace engineer? No (but my brother is, so if I get stuck I'll just give him a call...lol). I can do this because Joralex has given me all the parts I need. I don't even have to worry about mutations, inversions, natural selection or any of that other science stuff...all I need is time.
I think that Joralex is trying to not only argue on the grounds of IC, but also on probabilities. I could be way off here, but I think he is also implying that not only is the most simple of eyes extrememly complex, but also the probability of all the needed "parts" evolving independently is so remote as to be functionally impossible. The problem with this sort of logic is that it goes against the whole concept of evolutonary theory, a point I think Zhimba has been deperately trying to make....you can't work backwards.
I predict that at some point during this debate, Joralex will agrue something along the lines that even a simple protein sequence is so complex that it (the protein) simply could not have evolved by chance. And if you can't get the protein (ie: one of the required "parts") then you certainly can't get even simple vision.
I have some other problems with his rebuttal, but I'll wait a bit and see if anyone else brings them up...I've probably bored and confused you enough already with what I'm trying to say versus what I actually said.

Replies to this message:
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Loudmouth
Inactive Member


Message 26 of 30 (71051)
12-04-2003 6:55 PM
Reply to: Message 25 by FliesOnly
12-04-2003 5:47 PM


In the first have of the above quote, Joralex informs us that we're trying to build a functional space shuttle and then gives us all the parts (what a nice guy). Then in the second half of the quote he seems to imply that we cannot possibly assemble an actual space shuttle because of its complexity. Ok, first off, we all know that evolution doesn't work that way. Evolution has no goal and cannot predict future novel contingencies, but hear me out. I'm saying that if you give me all the parts needed to assemble a space shuttle and enough time...I will give you back a functioning space shuttle.
Maybe the bigger question is, could we take the parts for the space shuttle and build a car. If we were allowed to cut and bend the metal (ie deletion and mutation) could we build something that resembles something so unique that no one would think that you made it out of space shuttle parts. I think that is what is missing from the IC inference, mutation and cooption can disguise the ancestory of many genes. So what if flagellar proteins are like no other protein, what matters is that they are trascribed from DNA and translated from RNA into an amino acid chain. In this respect, they are like every other protein.

This message is a reply to:
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FliesOnly
Member (Idle past 4145 days)
Posts: 797
From: Michigan
Joined: 12-01-2003


Message 27 of 30 (71175)
12-05-2003 10:02 AM


You're right Loudmouth, I thought of that last night after I had sent the previous thread, and was going to write words to that effect this morning. However, remember that my original point was merely to demonstrate that given the parts and plenty of time, I ( or should I now say "we", cuz it appears that at least you and I are in this together ) could assemble a space shuttle. A more "realistic" scenario would be to first accept the parts so generously donated by Joralex and then, by following the basic rules of evolutionary theory and letting "nature" run its course, see what we () get.
But back to the debate in question.
Joralex writes:
I wouldn't word it that way. There exists an immense variety of eyes - this much is clear. It is then the claim of the evolutionist that this observation supports the hypothesis that complex eyes evolved from simpler eyes which, in turn, came from no eyes. IOW, the evolutionist takes this variety and sequences them in some order that suggests A --> B --> C --> D --> etc... The logical/scientific necessity of such a progression is ... missing.
Read that last sentence..."necessity"... Arrrrrg, he just doesn't undersatnd! Of course necessity is missing Joralex, evolutin has no goal. Do you actually think organisms were trying to evolve a visual system? That if they "wished" hard enough, they could get the mutations they wanted and vision would start to evolve? Not to mention that no evolutionist suggests that any pathway is as simple as A---> B---> C---> D---> etc.
And then he gives us this:
Joralex writes:
However, there is much more to this as you have observed (below)...
quote:
--------------------------------------------------------------------------------
Visual pigments belong to a very large family of structurally similar transmembrane proteins that act as receptor molecules in a wide range of different cell types: all function through the activation of a G-protein that binds guanosine triphosphate (GTP). The family includes not only all the visual pigments, but also acetylcholine muscarinic receptors (of which there may be at least five pharmacologically distinct subtypes), noradrenergic receptors (again at least five subtypes), serotonin or 5-hydroxytryptamine (5-HT) receptors (at least 3 subtypes), dopaminergic receptors and probably many others. (Bowmaker, The evolution of vertebrate visual pigments and photoreceptors, in Cronly-Dillon/Gregory, eds., Evolution of the Eye and Visual System)
--------------------------------------------------------------------------------
Zhimbo - did you read your own material? Tell me, what do you find "simple" in this process? In my last post I used the words "or a process that parallels this". Yes, what I described concerned the retina, but any other 'seeing process' - even a single-celled variety - involves a series of very specialized and complex chemical reactions just to enable "seeing". Then, what is "seen" must (if it is to satisfy the definition of sight) invoke a response and a cascade of changes in the organism (e.g., moving towards or away from a light source) and, finally, the "seeing" apparatus must return to its ground state to enable it to be in the receive mode once again. There is absolutely nothing "simple" about this and your above example only serves to accentuate this point further.
What process he is talking about? I don't see a process, I see a list of structurally similar transmembrane proteins. If anything, this supports the idea of co-option.
And lastly, we get this:
joralex writes:
You are committing the fallacy of most Naturalists/evolutionists : assuming that "because we are here then that 'proves' that evolution happened". No! : all sorts of "eye" variations exist but this doesn't lend any support to "they evolved that way". That is precisely what we are disputing here : is it more reasonable to think of the eye as a created structure or as an evolved one? Alternatively : is it more rational to think of the eye as having evolved or as having been created?
There have been quite e few threads giving perfectly valid, scientifically plausible evolutionary pathways explaining how a simple light detecting system could evolve. Joralex simply ignores them or dismisses them as fallacies. Rei, for example, explained rather eloquently how a sensor rhodopsin gene can mutate into a photorhodopsin. She ( I think I read somewhere that she is a she, not a he...if I'm mistaken, my apologies to Rei) also demonstarted that such a mutation has a very high probability of occurring...almost to the point of certainty. Of course, we all know that she cannot "prove" that this was indeed the pathway that opened our eyes , but neither can Joralex simply dismiss it as false because it gives him a wedgie. And to answer that last sentence/question, I'll ask this: Is it more rational to think that all those nice presents I received as a child were brought to me by my parents or by Santa Claus?

Replies to this message:
 Message 28 by Thronacx, posted 12-05-2003 12:35 PM FliesOnly has not replied
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Thronacx
Inactive Member


Message 28 of 30 (71207)
12-05-2003 12:35 PM
Reply to: Message 27 by FliesOnly
12-05-2003 10:02 AM


It seems to me that joralex was trying to make the point: that it all comes to down whether or not you believe that:
Order -----> Chaos (creation)
OR
Chaos -----> Order (evolution)

This message is a reply to:
 Message 27 by FliesOnly, posted 12-05-2003 10:02 AM FliesOnly has not replied

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Chiroptera
Inactive Member


Message 29 of 30 (71216)
12-05-2003 12:52 PM
Reply to: Message 28 by Thronacx
12-05-2003 12:35 PM


Hello, Thronacx.
But such beliefs are not the point of the debate. The debate is on what does the factual evidence, and reasonable logical inferences based on the evidence, tell us about the real world. Either statement must be backed up by evidence.
Anyway, evolution does not say order comes from chaos. That would violate the Second Law of Thermodynamics, and the Theory of Evolution is as constrained by that principle as any other scientific theory. While it is true that evolution seems to lead to greater order out of chaos, it does come by an overall decrease in entropy in the universe.

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Loudmouth
Inactive Member


Message 30 of 30 (71230)
12-05-2003 1:57 PM
Reply to: Message 27 by FliesOnly
12-05-2003 10:02 AM


What process he is talking about? I don't see a process, I see a list of structurally similar transmembrane proteins. If anything, this supports the idea of co-option.
I don't know about your scientific background, but I find that anyone that has studied the cell in any detail tends to feel the same way. There is nothing "special" about the proteins involved in sight, and yes it does seem to indicate co-option. Maybe for people like myself who have worked intimately with the workings of prokaryotic and eukaryotic cells they start to lose some of their mystery. Some people scream "look at this complexity" as if it is unknowable and beyond understanding when in fact we already know quite a bit about the complexity found in cells (Tol like receptors in innate immune response probably being the latest and greatest). It is something akin to a child amazed by the inner workings of a clock and then later in life becoming a watchmaker.

This message is a reply to:
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