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Author Topic:   Should we have bunches of neutral body parts?
gman
Inactive Member


Message 1 of 35 (147245)
10-04-2004 5:46 PM


-------------
Life is full of irreducibly complex systems. (If you take a part out of it, it will not work.) So how would one of these systems evolve? Below is an example of how it might happen, but if it did happen this way, everything should have a huge number of random, neutral body parts.
- Evolving a mouse trap - (a very simple irreducibly complex system)
1. Mutation creates the platform (Neutral trait)
2. A few generations pass so that the gene has time to be passed to many of the species.
3. Another mutation takes place, that has the following traits.
- The trait is either helpful or neutral
- Can be passed on to the next generation
- Is one of the shapes needed to form the final trap. (Catch,
holding bar, hammer, or spring)
- Is located in the correct place in the body to be part of the
mousetrap.
4. Repeat 2 and 3 until all the parts are formed.
If it did happen this way everything should have a huge number of random neutral body parts because of the third step.
It is more probable that the neutral, pass-on-able traits would neither be in the correct location, or shape.
The random traits that don't fit into the final product would always be produced faster than traits that do fit into the final product.
-----------
Is the scenario described above simply setting up a straw man? If so, why.
Is the reasoning behind expecting a huge number of random body parts a sound argument? If not, explain why.
Does life have a huge number of neutral, non-functional body parts?

Replies to this message:
 Message 3 by PaulK, posted 10-05-2004 11:56 AM gman has replied
 Message 5 by coffee_addict, posted 10-05-2004 3:37 PM gman has not replied
 Message 7 by arachnophilia, posted 10-05-2004 5:06 PM gman has not replied
 Message 17 by mick, posted 02-22-2005 12:28 PM gman has not replied
 Message 18 by Electron, posted 02-24-2005 7:14 AM gman has not replied
 Message 32 by Brad McFall, posted 02-25-2005 6:39 PM gman has not replied

  
AdminNosy
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Posts: 4755
From: Vancouver, BC, Canada
Joined: 11-11-2003


Message 2 of 35 (147467)
10-05-2004 11:29 AM


Thread moved here from the Proposed New Topics forum.

  
PaulK
Member
Posts: 17918
Joined: 01-10-2003
Member Rating: 6.7


Message 3 of 35 (147479)
10-05-2004 11:56 AM
Reply to: Message 1 by gman
10-04-2004 5:46 PM


I think that it is something of a strawman.
Firstly, the analogy to a moustrap is far from being entirely accurate.
Secondly, Behe focusses exclusively on biochemistry so if we are following Behe's argument the only "parts" we should be looking at are individual gene-products (and ultimately genes.
Thirdly, "new" body will be relatively rare and inobvious. We are more likely to see neutral modifications to an existing "part".
Fourthly, and this further developes the third point, all but the simplest examples of Behe's IC are likely to come from coopting the workings of existing parts which evolved for other functions entirely. The idea that the whole structure must evolve in a single "go" for the current function is itself a strawman - and one the argument from IC relies on.

This message is a reply to:
 Message 1 by gman, posted 10-04-2004 5:46 PM gman has replied

Replies to this message:
 Message 4 by gman, posted 10-05-2004 3:30 PM PaulK has replied

  
gman
Inactive Member


Message 4 of 35 (147559)
10-05-2004 3:30 PM
Reply to: Message 3 by PaulK
10-05-2004 11:56 AM


1. Lets replace Catch,
holding bar, etc.. with Optic nerve, fovea, lense, etc...
2. We are not following behe's argument.
3. When I said "a mutation creates.." I did not mean to imply that it came out of no-where. Assuming it is from a modification of some other part would not change the fact that it would be a neutral part.
4. It sounds like your saying the idividual parts would not be neutral after all. The forvea, lense, etc.. would all be evolved for different systems in the same area, but then by chance be right next to each other , so that they end up fitting together as an eye? If this is not what you are saying please explain in greater detail, and if possible give me an example.

This message is a reply to:
 Message 3 by PaulK, posted 10-05-2004 11:56 AM PaulK has replied

Replies to this message:
 Message 8 by PaulK, posted 10-05-2004 6:52 PM gman has replied

  
coffee_addict
Member (Idle past 122 days)
Posts: 3645
From: Indianapolis, IN
Joined: 03-29-2004


Message 5 of 35 (147564)
10-05-2004 3:37 PM
Reply to: Message 1 by gman
10-04-2004 5:46 PM


gman writes:
Should we have bunches of neutral body parts?
Lots of neutral body parts would not be neutral at all. It would be disadvantagious to have lots of neutral body parts, which natural selection would prevent from happening.

This message is a reply to:
 Message 1 by gman, posted 10-04-2004 5:46 PM gman has not replied

  
dpardo
Inactive Member


Message 6 of 35 (147595)
10-05-2004 4:38 PM


Gman,
Can you please elaborate further on what you mean by "bunches of neutral body parts"?

  
arachnophilia
Member (Idle past 1598 days)
Posts: 9069
From: god's waiting room
Joined: 05-21-2004


Message 7 of 35 (147611)
10-05-2004 5:06 PM
Reply to: Message 1 by gman
10-04-2004 5:46 PM


i'm not sure if this argument helps or hurts the evolutionary viewpoint, but check this out
if it doesn't show, go here: http://www.geocities.com/Athens/Rhodes/3991/Mousetraps.html
here's another way to do it: Page Not Found | Department of Chemistry
notice that there are not parts which are not useful in each step (no forward planning)

This message is a reply to:
 Message 1 by gman, posted 10-04-2004 5:46 PM gman has not replied

  
PaulK
Member
Posts: 17918
Joined: 01-10-2003
Member Rating: 6.7


Message 8 of 35 (147632)
10-05-2004 6:52 PM
Reply to: Message 4 by gman
10-05-2004 3:30 PM


1) You really think that they eye evolved by parts just appearing ?
2) You're using IC and a mousetrap as an example so I guess you are following Behe's argument. And Behe certainly didn't use the sort of anatomical examples you are trying to. Isn't it likely that Behe knows something you don't ?
3) So the fact that the neutral trait is a modification to a functional (and therfore beneficial_ part suddenly makes the part non-functional ? No that would be a detrimental mutation.
4) The eye isn't an IC system - the lens for instance is not necessary.
But given an example of the sort I am suggesting "chance" is misleading - evolution makes use of what is available. Statistically the chance that SOME useful coincidences will turn up is almost a certainty.

This message is a reply to:
 Message 4 by gman, posted 10-05-2004 3:30 PM gman has replied

Replies to this message:
 Message 9 by gman, posted 10-06-2004 11:34 AM PaulK has replied

  
gman
Inactive Member


Message 9 of 35 (147775)
10-06-2004 11:34 AM
Reply to: Message 8 by PaulK
10-05-2004 6:52 PM


When I put #1, 2, 3, 4 in my last entry I was specifically responding to your comments, "Firstly.. secondly..thirdly.. fourthly..." From now on I will paste your words into my frame before responding to them. Let me try again.
Paulk - "1)You really think that they eye evolved by parts just appearing ?"
I think you should also start to copy and paste the sections you are respoding to, because I never said anything about "parts just appearing". I specifically said I DO NOT believe in parts "just appearing" . I said...
Gman - "When I said "a mutation creates.." I did not mean to imply that it came out of no-where."
Paulk - "3) So the fact that the neutral trait is a modification to a functional (and therfore beneficial_ part suddenly makes the part non-functional ? No that would be a detrimental mutation."
I never said they were non-functional, but I can see how you thought I did. When I said...
Gman - "It sounds like your saying the idividual parts would not be neutral after all." I ment to imply that they would be benificial rather than neutral, because you said they would have "evolved for other functions entirely."
Paulk - "4) The eye isn't an IC system - the lens for instance is not necessary.
Ok, I guess the ability to focus could be considered non-essential. But the retina, optic nerve, and neural pathways in the brain able to translate and interpret the message would be essential before the eye has any effect at all. So lest just work with these parts. An IC system now, right?
Paulk - "But given an example of the sort I am suggesting "chance" is misleading - evolution makes use of what is available. Statistically the chance that SOME useful coincidences will turn up is almost a certainty.""
From now on I will say "by trial and error" instead of "by chance".

This message is a reply to:
 Message 8 by PaulK, posted 10-05-2004 6:52 PM PaulK has replied

Replies to this message:
 Message 10 by CK, posted 10-06-2004 11:39 AM gman has not replied
 Message 11 by PaulK, posted 10-06-2004 11:46 AM gman has replied

  
CK
Member (Idle past 4382 days)
Posts: 3221
Joined: 07-04-2004


Message 10 of 35 (147777)
10-06-2004 11:39 AM
Reply to: Message 9 by gman
10-06-2004 11:34 AM


quote:
When I put #1, 2, 3, 4 in my last entry I was specifically responding to your comments, "Firstly.. secondly..thirdly.. fourthly..." From now on I will paste your words into my frame before responding to them. Let me try again.
Gmail - if you want to quote people clicking on ubb code is on - will tell you how to format.

This message is a reply to:
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PaulK
Member
Posts: 17918
Joined: 01-10-2003
Member Rating: 6.7


Message 11 of 35 (147781)
10-06-2004 11:46 AM
Reply to: Message 9 by gman
10-06-2004 11:34 AM


Your argument that we should have many neutral body parts relies on equating "trait" to "body part". Once you accept that the majority of traits are properties of body parts (in a very general sense) then it follows that "many neutral traits" does not mean "many neutral parts"
As to the eye, a single celled organism can get use out of a light sensitive spot. It has no retina, no optic nerve and no brain. Now you may argue that that is not an eye, but evolution does not care about our labels and classification systems. It is clearly at least a possible - if distant - precursor of an eye.

This message is a reply to:
 Message 9 by gman, posted 10-06-2004 11:34 AM gman has replied

Replies to this message:
 Message 12 by gman, posted 10-06-2004 1:59 PM PaulK has replied

  
gman
Inactive Member


Message 12 of 35 (147820)
10-06-2004 1:59 PM
Reply to: Message 11 by PaulK
10-06-2004 11:46 AM


Your argument that we should have many neutral body parts relies on equating "trait" to "body part". Once you accept that the majority of traits are properties of body parts (in a very general sense) then it follows that "many neutral traits" does not mean "many neutral parts"
I think this argument is sufficient. I'm dropping the "should we have lots of neutral traits?" question
But...I still want to better clarify how apparently IC systems could develope.
So, first of all, how does a single celled organism get use of a light sensitive spot?

This message is a reply to:
 Message 11 by PaulK, posted 10-06-2004 11:46 AM PaulK has replied

Replies to this message:
 Message 13 by PaulK, posted 10-06-2004 2:45 PM gman has replied

  
PaulK
Member
Posts: 17918
Joined: 01-10-2003
Member Rating: 6.7


Message 13 of 35 (147832)
10-06-2004 2:45 PM
Reply to: Message 12 by gman
10-06-2004 1:59 PM


For a single-celled organism to get the use of a light sensitive spot basically requires that it make a light sensitive chemical (and that's pretty easy) and that the chemical reaction that occurs when light hits it influences the organism's behaviour in a useful way (since the behaviour ultimately is chemical the only difficult bit, really is the "useful" part). The behaviour can be as simple as moving toward or awat from the light. Localising the chemical in a single spot can be left for later evolution (the benefit of that is more precision in locating light sources).

This message is a reply to:
 Message 12 by gman, posted 10-06-2004 1:59 PM gman has replied

Replies to this message:
 Message 14 by gman, posted 10-06-2004 6:55 PM PaulK has replied

  
gman
Inactive Member


Message 14 of 35 (147897)
10-06-2004 6:55 PM
Reply to: Message 13 by PaulK
10-06-2004 2:45 PM


So would it be correct to say that the retina would prabably evolve first and then the rest of the eye would, through mutational trial and error build upon that foundation (each step being helpfull) until it is an eye?
Do you know of any resources that would go through the process of how a retina would evolve from the light-sensitive chemicals?

This message is a reply to:
 Message 13 by PaulK, posted 10-06-2004 2:45 PM PaulK has replied

Replies to this message:
 Message 15 by PaulK, posted 10-06-2004 7:16 PM gman has not replied
 Message 16 by jar, posted 10-06-2004 7:37 PM gman has not replied
 Message 19 by Loudmouth, posted 02-24-2005 12:21 PM gman has not replied

  
PaulK
Member
Posts: 17918
Joined: 01-10-2003
Member Rating: 6.7


Message 15 of 35 (147903)
10-06-2004 7:16 PM
Reply to: Message 14 by gman
10-06-2004 6:55 PM


That depends on what you count as a retina, and what you count as an eye. Light sensitivity almost certainly has to be one of the the first steps since the rest seems to make no sense without it. The lens on the other hand is very likely a relatively late development because even now nautiloids have eyes without lenses that focus on the same principle as a "pin-hole" camera.
Now I don't know of any resources off hand on how the retina developed - and it would depend on how multicellular life evolved. Which we really don't knwo a lot about yet, although research is discovering more On the view that multicellular life started as colonial single-celled life and that there followed a period of growing specialisation and integration it might be that the first step was the first stages towards a nervous system - a communication channel. That step allows some cells to specialise in light-detection while others abandon it to devote their resources to other functions.
Now even bacteria (or at least some species) can communicate to some extent by chemical means, so maybe that developed seperately and then came together with light sensitivity - or even maybe intercellular communications came first and light sensitivity worked through that. But it's hard to call chemical communications between cells any sort of eye at all.

This message is a reply to:
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