Re: Sequence Homology

Arthur V. Chadwick (
Mon, 15 Dec 1997 10:55:22 -0800

At 09:36 AM 12/15/97 -0600, Joel wrote:
>Here is my short response, I'll try to put together a more explicit example
>later. My first reaction is to point out the number of times that one can
>reconstruct phylogentic relationships of a particular group with different
>genes and get the same result. Etc.

I would like to suggest that logically this line of reasoning is consistent
equally with an evolutionary hypothesis and with creation by a God who was
wise enough to realize (as sometimes we ourselves seem not to be) that the
more similar two organisms are, the more similar their (whatever) need to

The question I would like to see addressed is the following: (specifically
to the issue raised by Lorne) The very complex (some are 24 pass proteins
with gates and in the case of the sodium channel, a ball and chain to plug
the channel temporarily while the gate is reestablished) ion channel
proteins of insects and humans are essentially identical in structure
(ignoring for the moment the differences in amino acid composition which
fit the molecules for their specific environments) and in function to the
point that most of what we knew about the system in humans we have learned
from the study of the system in insects (up until the last few years when
recombinant technology came in). Focusing attention on the minor
differences that distinguish organisms from one another only serves to beg
the question about the origin of the complexity itself. For this we are
left with a giant question mark.

If evolution is the correct explanation for origins, then the common
ancestor of insects and man must have had these same ion channel proteins
in essentially their current configuration. The same logic applies to
virtually all of the molecular complexity recognized in modern organisms,
including the developmental genes and the general scheme of development
shared by insects and man. Since morphological change is now clearly
recognized as a manifestation of the variable expression of the underlying
developmental genes and the molecular complexity shared by all organisms,
it is not difficult to see that essentially all evolution of shared
molecular complexity is required to have occurred in the Precambrian before
there was any record of anything more complex than a carbonized film of
single cells. I do not see how this differs in scientific value from
saying that a Creator did it. At least in the latter case we have an
intellectually plausible scenario.