Re: Intelligent design vs. natural selection

John P. McKiness (jmckines@blue.weeg.uiowa.edu)
Sat, 6 Sep 1997 14:01:22 -0500

At 09:55 PM 9/4/97 -0400, David wrote:
>>> On Wed, 3 Sep 1997, Pattle Pun wrote:
>>> > One of the ways by which intelligent design theory can be tested is by
>>> > way of following the patterns of sequence homologies of macromolecules
>>> > that cannot be accommodated by the the monophyletic assumption of the
>>> > comment descent hypothesis, but rather by a polyphyletic lineage with a
>>> > common pattern (or "design"). Preliminary evidence has already indicated
>>> > that the three distinct "urkingdoms" of Archea, Bacteria, and Eukarya have
>>> > unique patterns within themselves such as rRNA, RNA polymerase, Cell
>>> > Walls, Lipid compositions, and translational machineries. Current models
>>> > of forcing these data into monophyletic interpretation are farfetched.
> Phylogenies connecting all three urkingdoms have been made based on
>rRNA, tRNA, heat shock proteins, and several other molecules. The split
>between the three is probably over 3.5 billion years ago, so large
>differences are to be expected. Gene transfers seem to have occurred in
>many cases, so these phylogenies will not always agree with each other, but
>the basic biochemical similarities among all living organisms seem best
>explained by the suggestion that God created them all from a common
>ancestor-the commonalities are greater than is necessary for function.
>However, multiple origins of life are possible under a naturalistic
>scenario, so this would not unambiguously test ID versus "methodological
>naturalism".
>
>David Campbell
>
>

David,

I think you last sentence is important enough that we need to take another
look at a built-in problem with systematics. With the standard models of
evolution we follow Darwin and others in the idea of common descent so our
tree/shrub diagrams always lead back to a common stem. We relate all
organisms by similar characteristics (or differences) but assume a common
ancestor.

I think that at this point in evolutionary biology we need to rethink the
common ancestor of the first lineages and think instead of similar chemical
environments of origin. Maybe the only similarities are that earliest
organisms were carbon based organisms in the same ocean about 4,000,000,000
years ago.

John
*********************
John P. McKiness
P.O. Box 5666
Coralville, Iowa 52241

jmckines@blue.weeg.uiowa.edu