Bacterial Flagella: A Paradigm for Design

Originally posted by googlefudge
To the mods.

This thread has nothing whatsoever to do with science or scientific discussion.

Please move to spirituality.

It certainly is science. You are only objecting because of the implications. But perhaps it would be best to take the advice of the person in the following referenced article:

http://www.sciencedaily.com/releases/2010/04/100413170731.htm

The Instructor

Originally posted by DeepThought
In the case of bacterial flagella it appears to be a modification to the Type 3 secretion system.

That may be true. However, the modification of one design for a different purpose or for added fuctionality is common among human engineers and designers of mechanical machines. Therefore, that does not mean molecular machines evolved, because we have absolute proof that mechanical machines did not evolve, even though they may look that way.

The Instructor

Originally posted by RJHinds
That may be true. However, the modification of one design for a different purpose or for added fuctionality is common among human engineers and designers of mechanical machines. Therefore, that does not mean molecular machines evolved, because we have absolute proof that mechanical machines did not evolve, even though they may look that way.

The Instructor

However, the modification of one design for a different purpose or for added fuctionality is common among human engineers and designers of mechanical machines.

How do you know bacterial flagella have a purpose? If you don't know this, then your analogy doesn't apply.

Originally posted by humy

However, the modification of one design for a different [b]purpose or for added fuctionality is common among human engineers and designers of mechanical machines.

How do you know bacterial flagella have a purpose? If you don't know this, then your analogy doesn't apply.[/b]

You don't have any problem with your Evilution scientist making assumptions about how it evolved. So what is so wrong about my assuming that something that has been observed by scientist to exhibit intelligent design was made by the designer for a purpose? I would be just as happy for no one to assume anything, if you wish, for that would eliminate the theory of Evilution which has never been observed.

The Instructor

The Instructor

Originally posted by RJHinds
That may be true. However, the modification of one design for a different purpose or for added fuctionality is common among human engineers and designers of mechanical machines. Therefore, that does not mean molecular machines evolved, because we have absolute proof that mechanical machines did not evolve, even though they may look that way.

The Instructor

The entire basis for the argument that bacterial flagella could not have evolved is due the the argument that it is "irreducibly complex", and therefore could not have evolved from some other form or function in an organism.

With the information that the flagellum contains all of the components of a Type III secretory system, we can see that the flagellum is not irreducibly complex, since something less complex exists that uses fewer components and is still functional.

Now you say that doesn't matter...

There are two ways you can argue your point here:
a) Prove that Evolutionary theory is bogus. Proving that a flagellum is irreducibly complex and cannot have evolved would accomplish this. However, your argument fell apart, the flagellum is not irreducibly complex. Argument refuted.

b) Prove that intelligent design occured. No evidence given...

Frequently raised but weak arguments against Intelligent Design

http://www.uncommondescent.com/faq/

The Instructor

Originally posted by forkedknight
The entire basis for the argument that bacterial flagella could not have evolved is due the the argument that it is "irreducibly complex", and therefore could not have evolved from some other form or function in an organism.

With the information that the flagellum contains all of the components of a Type III secretory system, we can see that the flag omplex. Argument refuted.

b) Prove that intelligent design occured. No evidence given...

Actually 'irreducible complexity' can occur, And indeed might be expected to occur,
in evolution.
And thus even if you find an 'irreducibly complex' system you have not in fact just
proved that that system couldn't have evolved.

For example...

Suppose you have a simple single cell organism that requires from it's environment
substance A and substance B.

On the surface of this single cell organism there is a receptor substance A and a
receptor for substance B.

Substance A is very common but B is very rare, and so this organism is restricted in
it's growth and spread by the availability of substance B.

Then one of the organisms develops the ability to convert substance A into substance
B.

As substance A is very common the organism can now make all the substance B it
needs from substance A and thus is no longer restricted to locations where there
are high enough concentrations of substance B.

This is a huge evolutionary advantage and cells with this mutation rapidly out-compete
cells without it.

As these new cells colonise areas with little of no substance B the substance B receptor
becomes redundant.

As this structure is no-longer needed and has an energy/complexity cost to produce there
is evolutionary pressure against it. Mutations in DNA that effect it don't come with an instant
penalty as it's a useless appendage, and so either gets recycled to make some new feature...
Or it just disappears entirely.

We now have a creature that requires substance A and substance B to survive.
But only has a receptor for substance A, and must produce substance B from substance A
to survive.

At this point someone from the ID crowd shouts 'irreducible complexity' as the cell can't
survive unless it has both a fully functioning substance A receptor AND a fully functioning
substance A to substance B converter. And they say that it is highly implausible that both
evolved at exactly the same time and thus the creature couldn't have evolved.



Irreducible complexity is not a problem for evolution. It's predicted by it.



EDIT: And RJHinds threads still don't belong in science, and should be booted.

EDIT2: Oh and I meant to say... While those are my own words, that is not my own example of
irreducible complexity arising naturally via evolution. I came across that example somewhere on
the web around a year ago and cannot for the life of me remember where.
Otherwise I would cite the source.

Irreducible complexity means that the function of a complex machine is not maintained if we take away any of its core parts. Behe’s main argument is that Irreducible complex machines like the flagellum cannot reasonably be the product of direct Darwinian pathways, because the function only emerges when the machine is wholly assembled, and therefore cannot be selected before. That is supported by the observation that there are no technically detailed descriptions of such pathways in the scientific literature.

So, Darwinists have tried to devise for Irreducible complex machines indirect Darwinian pathways, using the notion of cooption, or exaptation, which more or less means: even if the parts or sub-assemblies of the machine cannot express the final function, they can have different functions, be selected for them, and then be coopted for the new function.

The TTSS (Type Three Secretory System) is suggested as an example of such a possible co-opted mechanism. The Darwinist argument is that there is strong homology between the proteins of the TTSS and a subset of the proteins of the flagellum which are part of a substructure in the basal body of the flagellum itself. Therefore, the flagellum could have reutilized an existing system.

The hypothesis has some empirical basis in the homology between the two systems: but that should not surprise us, because both the TTSS and the “homologue” subset in the flagellum accomplish a similar function: they pump proteins through a membrane. So, it is somewhat like saying that an airplane and a cart are similar because both have wheels. It is true, but an airplane is not a cart. For, the flagellum is not a TTSS; it is much more. And the sub-machine which pumps proteins in the basal body of the flagellum is similar to, but not the same as the TTSS. It is at least as credible to argue that the TTSS is a devolution, than that it is a candidate prior functional sub-assembly.

Even if the functions of the TTSS and of the sub-machine in the flagellum are similar, the two machines are in fact different,and the proteins in the two machines are not the same. Homology does not mean identity. The overall function of the flagellum cannot be accomplished by any simpler subset. That means that the flagellum is irreducibly complex. And anyway, the TTSS itself is irreducibly complex.

http://www.uncommondescent.com/faq/

Originally posted by googlefudge
Actually 'irreducible complexity' can occur, And indeed might be expected to occur,
in evolution.
And thus even if you find an 'irreducibly complex' system you have not in fact just
proved that that system couldn't have evolved.

For example...

Suppose you have a simple single cell organism that requires from it's environment
substance A and ...[text shortened]... and cannot for the life of me remember where.
Otherwise I would cite the source.

You give a hypothetical argumen,t but that is nothing new in Evilution Theory, because it all depends on hypotheticals that have never been shown to happened, like an ape turning into a man.

The Instructor

Originally posted by RJHinds
You give a hypothetical argumen,t but that is nothing new in Evilution Theory, because it all depends on hypotheticals that have never been shown to happened, like an ape turning into a man.

The Instructor

You are such an assshole. You know good and well men did not come from apes but you keep putting up that as an objection when everyone knows that is not even close to true.

CO-Option

YouTube

The Instructor

Originally posted by sonhouse
You are such an assshole. You know good and well men did not come from apes but you keep putting up that as an objection when everyone knows that is not even close to true.

Have you come up with a theory of your own? If we did not turn from ape to man, then did we turn directly from the frog to a prince? I know you don't believe we were created in the image of God and made directly by God. So what is your new theory?

The Instructor

The brain is another example of intelligent design of our creator God.

http://us.yhs4.search.yahoo.com/yhs/search?hspart=Babylon&hsimp=yhs-002&type=br101dm25&p=how%20the%20brain%20works

YouTube

The Miracle in Human Brain

YouTube&NR=1&feature=endscreen

The Instructor

Human Gestation and the Feasts of the Lord. Coincidence or Intelligent Design?

YouTube

The Instructor

Originally posted by RJHinds
Have you come up with a theory of your own? If we did not turn from ape to man, then did we turn directly from the frog to a prince? I know you don't believe we were created in the image of God and made directly by God. So what is your new theory?

The Instructor

Men are apes. I am sure you have been told this before but refused to accept it on religious grounds. But no matter what your religious beliefs, the standard modern scientific meaning of 'ape' includes humans.
Of course you are free to come up with your own definition, but then you have to give us that definition before we can communicate on the matter.