>
>Nelson:
>I disagree. I think that IC is is clearly defined and does indeed apply to
>the bacterial flagellum. As link itself states:
>
>"When viewed as a motile stucture, the flagella is IC."
>
>Thus it is realized that IC means:
>
>"a single system which is composed of several well-matched, interacting
>parts that contribute to the basic function, and where the removal of any
>one of the parts causes the system to effectively cease functioning."
>
>Although the definition is useful, I do concede that it is not precise. As
>another IDist has pointed out, in Biology it is difficult to be precise.
>This is simply the nature of Biology:
Ralph:
I want to be sure that I am understanding this definition correctly and
perhaps my confusion falls under your concession that the definition
is not precise. It seems to me that, once you strip away non-essential
parts, you will reach a point with *any* biological unit where taking away
one more part will cause the unit to cease functioning. Is it at this
point that you are declaring the unit to be IC?
Nelson:
It is a determination of what minimal parts are needed for the system to
function. On this basis, if I remove one part from this minimal set, and the
system is rendered functionless, I am safe to conclude that the system is
irreducibly complex.
Ralph:
There is no biological
entity (that I know of) that can continue to function if you completely
dismantle it. Therefore, it seems to me, by this definition, every living
thing must be declared IC. Is that correct?
Nelson:
No. For example the function may be reducible to it's parts. Like the heme
in hemoglobin. FlgB from the bacterial flagellum will not cause rotary
motion, it must work in interactively with other parts to be a flagellum.
Cliff gave me a structure,namely a calculator. I see that the calculator is
complex and has function. Now which parts can I remove until I lose
function? And when I do so, do those parts work interactively and are
well-matched to contribute to that basic function? Those are the kinds of
tests to conduct when determining what an IC system is.
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