Irreducible Complexity.

[CoxRox]

Is there such at thing as irreducible complexity within living things? I will cite Behe's example of a non living thing: a mouse trap. I am aware that there is much controversy regarding his living examples, (the flagellar motor for instance) and am keen to debate this important topic.

[leo-rcc]

Hi Catherine,

The fallacy in irreducible complexity is that it sometimes appears something can't work for the specific function if you take a component away. Even though this is not always the case, it is still very possible for components of that "irreducible complex" device to serve and work in different functions.

In the comparison of the mouse trap, a mousetrap without a lath can still serve a function, like a paper clip for instance. The wooden base can serve a function of striking a match on it. Now is a mouse trap not a good example since it is a non evolving thing, but the same breakdown of the components can be done with the flagellar motor which is an evolving mechanism.

Prof. Kenneth Miller has made a very good case for the flagellar motor, I will look up his lecture on it on youtube for you.

Basically the motor's core component is the secretory system of several eubacterial systems (it's anus if you will though that is technically incorrect).

Also for Reference:
http://rnaworld.bio.ku.edu/ribozone/reso...agella.htm

edit, found the lecture:

[youtube]srGYxZz9588[/youtube]

[Tiberius]

I believe Ken Miller actually wore the "mousetrap without the latch" as a tie-clip in the dover trial.

The flagella motor is not irreducibly complex though. A scientist found that the flagella motor is almost identical to a molecular syringe used to inject cells with proteins. The syringe looks very similar to the flagella, but is missing a few key parts that would make it a "motor".

[CoxRox]

Leo , regarding your first point (of which I hope I understood correctly)- : 'it is still very possible for components of that "irreducible complex" device to serve and work in different functions': Miller says this of the flagellum: 'By the logic of irreducible complexity, these individual components should have no function until all 30 are put into place, at which point the function of motility appears'

The article I've found discussing this says:

'This is a false deduction from Irreducible Complexity. IC does not forbid subsets of components of molecular machines being utilised in other molecular machines. IC simply asserts that there are multiple interacting components, the individual parts of which have no independent function.'

(http://www.idnet.com.au/files/pdf/Miller...Design.PDF)

Do you accept this point?

Regarding the mouse trap example, you can indeed find a 'different' use for the separate parts of the mouse trap, but by taking one part away you will no longer have a mouse trap. Do you accept this? If you take the base away you would still need to utilise a surface of some kind ie the floor, in order for it to function. I think that using a non living thing is probably not a good idea so we've got to head into complex territory of which I will possibly struggle and this is where I need your feedback. I'd already watched the youtube video you included, about four months ago and I found an article refuting Miller in that lecture. I will come back to you and Adrian, regarding the flagellar motor very soon.

regards Catherine[/size]

[leo-rcc]

Hi Catherine,

Leo , regarding your first point (of which I hope I understood correctly)- : 'it is still very possible for components of that "irreducible complex" device to serve and work in different functions': Miller says this of the flagellum: 'By the logic of irreducible complexity, these individual components should have no function until all 30 are put into place, at which point the function of motility appears'

Well Ken Miller has a better way of words than I, that is for sure. Basically we mean the same thing. What ID proposes is that all components need to be "designed" for a specific function to work, but there is no need for it to be designed in such a way in the first place. These things can simply evolve over time, when there is a evolutionary advantage for it that gives the organism an edge in natural selection.

The article I've found discussing this says:

'This is a false deduction from Irreducible Complexity. IC does not forbid subsets of components of molecular machines being utilised in other molecular machines. IC simply asserts that there are multiple interacting components, the individual parts of which have no independent function.'

(http://www.idnet.com.au/files/pdf/Miller...Design.PDF)

Do you accept this point?

No I don't. Because the individual parts may have had independent functions in the past which have gradually changed over to do a different task. Just like the bones in the inner ear are remnants of our reptilian jaws, it now serves a totally different purpose.

http://www.sciam.com/article.cfm?id=foss...-in-action

Regarding the mouse trap example, you can indeed find a 'different' use for the separate parts of the mouse trap, but by taking one part away you will no longer have a mouse trap. Do you accept this? If you take the base away you would still need to utilise a surface of some kind ie the floor, in order for it to function.

To function as a mousetrap, sure. But that is because human beings made that thing to serve that purpose.

In evolution there is no path to create something specific, just the premise that something that has a little more use than a previous arrangement gets an edge on other lifeforms that don't have that mutation. Natural selection will filter out most of the bad mutations, some of the good mutations, but overall the better mutations survive.

Therefore over time there will be more of the species with that edge over the others than the ones that don't, and than that becomes the norm. Now that edge might evolve even further, and then natural selection takes it course on that, and so on and so forth. And as time progresses, the mutations can become more complex and start to look more and more designed.

[CoxRox]

Hi Leo, the points you've just made will ease us nicely into this debate. I've just been compiling some info which hopefully covers these points. We're making a good start. I'm going to enjoy this. I'll come back to you shortly.

[Tiberius]

Regarding the mouse trap example, you can indeed find a 'different' use for the separate parts of the mouse trap, but by taking one part away you will no longer have a mouse trap. Do you accept this? If you take the base away you would still need to utilise a surface of some kind ie the floor, in order for it to function. I think that using a non living thing is probably not a good idea so we've got to head into complex territory of which I will possibly struggle and this is where I need your feedback.

I accept the fact that it no longer functions as a mouse trap, but that hasn't got anything to do with I.C.

Michael Behe (the guy who dreampt up I.C) came up with this definition:

an irreducibly complex system is one composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning.

So the mouse trap is not irreducibly complex. You can remove several parts and the system doesn't stop functioning; it just performs a different function. The same applies for the bacterial flagellum. You can remove several pieces and still get a syringe.

If I.C said that the system stops performing the same function after pieces are removed, then sure, both the mouse trap and the flagellum are irreducibly complex. However, it does not say this.

Even if it did however, this doesn't mean that these things cannot evolve through natural selection, because they still abide by the same constraints as the first definition.

[CoxRox]

Adrian, you are surely wrong on two counts: 1)To say it has nothing to do with IC and 2)to say it doesn't stop functioning. It will no longer function as a mouse trap which is the purpose of the combined parts. This is very clear to me and is a clear example of irreducible complexity. So I don't understand your first point??

You say: 'If I.C said that the system stops performing the same function after pieces are removed, then sure, both the mouse trap and the flagellum are irreducibly complex. However, it does not say this.'

I am struggling to see how it is not saying this. I've read many articles by ID supporters since reading Darwin's Black Box which appear to agree with your statement and this has no detrimental effect to the concept of IC. I will try to cover your last point about natural selection when I reply to Leo.

---

Leo, I'll start off with a quote if I may:

''Behe never suggests that subsystems cannot play some other role in the cell—in fact he suggests the opposite. Rather, Behe simply argues that evolution requires that the total system must be built up in a
slight, step-by-step fashion, where each step is functional.
Miller has mischaracterized irreducible complexity, and his test is a straw-test for refuting irreducible complexity. The test for irreducible complexity does not ask “can one small part of the macrosystem be used
to do something else?” as Miller claims, but rather asks “can the system as a whole be built in a step-by-step fashion which does not require any ‘non-slight’ modifications to gain the final target function?” Any nonslight modifications of complexity required to go from functional sub-part(s), operating outside-of the-final system, to the entire final functional system, represent the irreducible complexity of a
system.'

http://www.discovery.org/a/3718

Sorry that was a bit long. I said a similar thing in my last post to you and asked if you agreed and you said no. I am struggling to see why you say no. Adrian seems to be taking issue with this as well, so I think before we proceed to the 'gradual step by step' evolution of the system, and why I maintain this is 'impossible' if something is truly irreducibly complex , we need to clear up this point, if that is ok.

[leo-rcc]

Hi Catherine,

What is the definition of Irreducible complexity you are defending?

IC does not forbid subsets of components of molecular machines being utilised in other molecular machines. IC simply asserts that there are multiple interacting components, the individual parts of which have no independent function.'

bolding mine.

Which Adrian already pointed out doesn't count for the flagellar motor because a part does have an independent function. That that function is not the same is not an issue.

Adrian, you are surely wrong on two counts: 1)To say it has nothing to do with IC and 2)to say it doesn't stop functioning. It will no longer function as a mouse trap which is the purpose of the combined parts. This is very clear to me and is a clear example of irreducible complexity. So I don't understand your first point??

The point is that a mousetrap HAS a function. To catch mice. It is designed and optimized specifically for that function. The parts in living organisms as demonstrated throughout nature will serve a specific purpuse through gradual adaptation.

Leo, I'll start off with a quote if I may:

''Behe never suggests that subsystems cannot play some other role in the cell—in fact he suggests the opposite. Rather, Behe simply argues that evolution requires that the total system must be built up in a slight, step-by-step fashion, where each step is functional.

That is something I disagree with, if the change is not functional but not detrimental either, there is just a much chance of that change staying in the gene pool and being propagated. So there is no actual need for it to be functional, but it would help speed things along. But since there is no end goal or specific target, that is not a necessity.

Miller has mischaracterized irreducible complexity, and his test is a straw-test for refuting irreducible complexity. The test for irreducible complexity does not ask “can one small part of the macrosystem be used
to do something else?” as Miller claims, but rather asks “can the system as a whole be built in a step-by-step fashion which does not require any ‘non-slight’ modifications to gain the final target function?”

And there is the main problem with I.D. It claims there IS a target, a goal, we disagree on that point. I say there is no goal, no target, just if something works in favour of that organism it will filter through, and if not beneficial but not detrimental either it can stay or evolve out again, and if it is detrimental to the organism it will either evolve away or the organism will go extinct.

I said a similar thing in my last post to you and asked if you agreed and you said no. I am struggling to see why you say no.

And I still do say no.

Adrian seems to be taking issue with this as well, so I think before we proceed to the 'gradual step by step' evolution of the system, and why I maintain this is 'impossible' if something is truly irreducibly complex , we need to clear up this point, if that is ok.

Again, that would mean something is truly Irreducible Complex, but so far the example you have given doesn't show that it is.

Also for reference: http://users.frii.com/katana/Fli.htm

As a side-note, a number of sources that discuss flagellar mechanics are written by people who claim it as proof that bacteria were divinely created, rather than evolving, because of a principle called ‘irreducible complexity’, which claims that the flagellar structure is too complicated to have evolved, as it requires correct functioning of a large number of proteins, specifically including FliG, FliM, and FliN. The argument seems to run as follows: unnecessary genes randomly mutate, and it is unlikely in the extreme that all 40 (the number typically cited) of the proteins necessary for flagellar function could have somehow suddenly appeared at the same time and in the correct manner to form a macrostructure like the flagellum. No mention is made that Helicobacter pylori gets by with 33 proteins. One implication of this paper is that it is not necessary for FliM and FliN to be strictly conserved, but FliG must be basically invariant, reducing the number of strictly necessary proteins by another two.

[Tiberius]

Adrian, you are surely wrong on two counts: 1)To say it has nothing to do with IC and 2)to say it doesn't stop functioning. It will no longer function as a mouse trap which is the purpose of the combined parts. This is very clear to me and is a clear example of irreducible complexity. So I don't understand your first point??

You say: 'If I.C said that the system stops performing the same function after pieces are removed, then sure, both the mouse trap and the flagellum are irreducibly complex. However, it does not say this.'

I am struggling to see how it is not saying this. I've read many articles by ID supporters since reading Darwin's Black Box which appear to agree with your statement and this has no detrimental effect to the concept of IC. I will try to cover your last point about natural selection when I reply to Leo.

Irreducible Complexity as understood by the scientific community is where you cannot remove parts of a biological system and still have the system functioning. However, as many scientists have shown, there are biological systems that are simply extensions of already functioning systems. The bacterial flagellum is an extension of the bacterial syringe for example. There is no reason to suggest that these parts could not have evolved from each other. Thus, the bacterial flagellum is not Irreducibly Complex.

If however, your definition of I.C is that when you take any piece off of a biological system, the system loses it's original function, then I agree. There are instances of I.C in nature. However, this doesn't mean that these were designed or that they disprove Evolution anymore than the fact that a man cannot exist without a head disproves Evolution.

Leo, I'll start off with a quote if I may:

''Behe never suggests that subsystems cannot play some other role in the cell—in fact he suggests the opposite. Rather, Behe simply argues that evolution requires that the total system must be built up in a
slight, step-by-step fashion, where each step is functional.
Miller has mischaracterized irreducible complexity, and his test is a straw-test for refuting irreducible complexity. The test for irreducible complexity does not ask “can one small part of the macrosystem be used
to do something else?” as Miller claims, but rather asks “can the system as a whole be built in a step-by-step fashion which does not require any ‘non-slight’ modifications to gain the final target function?” Any nonslight modifications of complexity required to go from functional sub-part(s), operating outside-of the-final system, to the entire final functional system, represent the irreducible complexity of a
system.'

http://www.discovery.org/a/3718

Sorry that was a bit long. I said a similar thing in my last post to you and asked if you agreed and you said no. I am struggling to see why you say no. Adrian seems to be taking issue with this as well, so I think before we proceed to the 'gradual step by step' evolution of the system, and why I maintain this is 'impossible' if something is truly irreducibly complex , we need to clear up this point, if that is ok.

The problem with Behe's argument is that his summation of Evolution "Behe simply argues that evolution requires that the total system must be built up in a
slight, step-by-step fashion, where each step is functional." is wrong.

Evolution works nothing like this at all, since Evolution has no goals. Behe thinks that Evolution selects only the best and functional mutations, but this is simply not the case. Natural selection means that the organisms more fitted to survival will pass on their mutations. A mutation that is detrimental usually doesn't get passed on, but that doesn't mean that every mutation that is pass on is somehow "positive". There are mutations that are ineffective at doing anything, for instance: an extra finger (I'm keeping it large scale for ease of understanding). Extra fingers often aren't detrimental in any way, but neither are they advantageous. They also do not add to a function.

The same can be applied to the small scale, where bacterial mutations are often simply kept because they do not have any negative effects. These mutations may very well come in handy later on, at which point the addition of a new mutation causes them to have a function.

I hope you understand now.