-----Original Message-----
From: evolution-owner@lists.calvin.edu
[mailto:evolution-owner@lists.calvin.edu]On Behalf Of FMAJ1019@aol.com
Sent: Tuesday, September 12, 2000 11:45 AM
To: evolution@calvin.edu
Subject: Fwd: Flagellum Re: Definitions of ID
In a message dated 9/12/2000 8:43:40 AM Pacific Daylight Time, FMAJ1019
writes:
<< Fam:
Given the suggestion that the flagellum is IC and therefor shows evidence of
intelligent design and therefor intelligence I would like to offer the
follow
data points against this idea.
Ian Musgrave shows his views on evolution of the flagellum
http://x59.deja.com/[ST_rn=ps]/getdoc.xp?AN=598548093
archived at
http://www-personal.monash.edu.au/~ianm/flagella.htm
Nelson:
I would like to address these links. Ian here thinks that the flagellum,
because it has some parts similar to the secretory apparatus, evolved from
the type III secretory system.Thus all the parts could be removed and
selection will still be able to select for the flagellum since it is acting
as a secretion system. I like Tim's analogy when Ken Miller brought this
objection up:
FAM:
Ian has shown that indeed there are likely precursors to the system and
since
evolution uses pre-existing systems it is important to show that there parts
that are similar to other systems.
Nelson:
However,the Type III secretion is not a likely precursor to the flageller
system. When the facts shown in this posts are taken into consideration,
saying that the secretion system is a simpler ancestor to the flagellum is
ad hoc.
<< "We will not be impressed by the clever fellow who points
out that it could run down the street in the absence of wheels if you
put it on the back of an elephant, and argues that bikes with wheels
evolved spontaneously from bikes on the backs of elephants. " >>
FAM:
No such argument is made.
Nelson:
This is exactly the argument Ian made.
<<
But there is a more fundamental problem. The type III secretory system is
actually quite complex. And it contains quite a few other parts that it
needs for it's function. It also sits causally downstream from the
flagellum, which would indicate that it may have evolved from the flagellum
and not vice versa. In this review of a paper:
>>
FMA:
Complexity is no objection to an evolutionary mechanism.
Nelson:
My argument was not about complexity objecting to any evolutionary
mechanism.
<< Type III Secretion Machines: Bacterial Devices for Protein Delivery into
Host Cells
Jorge E. Galan and Alan Collmer
Science 1999 May 21; 284: 1322-1328.
"Made up of more than 20 proteins, type III secretion systems are the most
complex of all known protein secretion systems in bacteria. The observation
that these virulence-associated systems were always linked to phenotypes
related to interactions between bacterial pathogens and their animal or
plant hosts intrigued researchers in this field from the outset."
It goes on to say that they require many chaperones for many of it's
proteins.
>>
FMA:
Any of them irreducibly complex?
Nelson:
I would say the type III secretory system may turn out to be IC itself.
<< "Despite the architectural similarity between flagella and type III
systems,
the structural components of the needle complex share limited sequence
similarity with components of the flagellar basal body "
Thus the reductionist viewpoint's prediction is falsified. And to view the
flagellum as a type III system has no basis except as an apologetic. >>
FMA:
Hardly falsified.
Nelson:
It is indeed falsified.
FMA:
But perhaps you can tell us how ID designed the system?
Nelson:
I discussed in my response to Susan some of the methods intelligent agency
uses to produce molecular machines.
FMA:
Lacking such predictions, can we conclude that ID is falsified as well? See
how evolution leads to predictions and further research? What would ID do?
Nelson:
It does not lack such predictions. One can use the design principle of one
machine , to predict the principle of another.
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