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To: Ron C.
"A bacterial flagellum motor is about 60nm in diameter and its tail is 500nm long. ATP synthase is about 10x20 nm. Soon we'll be looking at live complex molecular machines running in real-time 3-D - a sight that will make the phrase 'natural selection' look as silly as the belief in a 'flat earth' during Medieval times."

Greetings, esteemed elder FReeper.

You seem to have been fortuitously exposed to Science at both ends of the physical size spectrum. How intriguing that must be!

Speaking of intriguing, I decided just on a hunch, to take a look at the "bacterial flagellum motor" from your post (to which I'm responding).

I found this relatively short, considering the complexity of the subject matter, description of both the structure and variations within bacterial flagella, and a plausible conjecture as to how it may have arisen.

The flagellum certainly is complex, even irreducibly complex in this canonical form, but can it evolve? Well, there is still a lot unknown about eubacterial flagella, but we can get some ideas, and a plausible pathway from the literature.
Interestingly, the author suggests quite seriously, that the bacterial flagellum motor may be an entirely accidental construct. From his descriptions, I get the impression that bacteria, in their teeming billions, are like sets of tinker-toys, getting assembled time after time with missing and extra parts that make them really, really odd.

And yet, an oddity such as a steering oar could be a useful contraption for a minuscule fluid-dwelling organism.

Apparently authored by Ian Musgrave, the article continues to hypothesize that bacterial flagella came about as a variation of normal secretory structures. I get the picture of Han, Luke, and Princess Leia stuck in the waste-disposal system, trying to assemble a device to assist them.

Evidently, some archaic proto-bacteria got its instructions mixed up and turned its trash into treasure in becoming marginally more motile.

It's also interesting that varieties of bacteria have developed different mechanisms for doing essentially the same thing. One wonders why, if the bacterial flagellum motor is so irreducibly complex, do countless different species use different tools, assembly procedures, and materials to do the same thing?

Here's a link to the short but interesting article. Evolution of the Bacterial Flagella

1,459 posted on 12/13/2009 11:54:22 AM PST by NicknamedBob (It seems to me that a wise PALINa woman would, more often than not, reach a better conclusion.)
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To: NicknamedBob; Ron C.
Here's a link to the short but interesting article. Evolution of the Bacterial Flagella

OK, from the link.....SECOND paragraph, mind you....

I recently ran across some material that bears directly on this question. In this article I'll outline the construction of eubacterial flagella, it's relationship to other systems, and end with a speculative scenario for the evolution of eubacterial flagella

Could you provide something a little more substantial with which to try to shoot down ID and IC?

1,468 posted on 12/13/2009 12:15:16 PM PST by metmom (Welfare was never meant to be a career choice.)
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To: NicknamedBob
And yet, an oddity such as a steering oar could be a useful contraption for a minuscule fluid-dwelling organism.

Maybe; if it knew where it was steering to!

Or..

...to where it was steering. (Fer the spelin' poltice.)

1,737 posted on 12/13/2009 5:18:31 PM PST by Elsie (Heck is where people, who don't believe in Gosh, think they are not going...)
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