Doug Hayworth wrote:
> I don't think the Doolittle stuff undermines the general reality of common
> ancestry, namely that descent with modification and the multiplication of
> species has characterized the history of life on earth.
Well, yes and no. If homology is separated from common ancestry,
then phylogenetic reconstruction will necessarily be transformed.
In short, what constitutes *evidence* for common ancestry becomes
an issue, and the history of life may end up looking profoundly
different from what is now taught.
> Yes, alternative modes of transmission that result in introgressive,
> reticulate, and horizontal "descent" and therefore cause a decoupling
> of different gene and organismal lineages, etc. do pose a problem
> for producing a single phylogenetic tree of life. This is old news. But
> this does not undo the reality of common ancestry in the broad sense.
I'm not sure what "the reality of common ancestry in the broad sense"
means. In any case, you underplay the significance of Doolittle's
ideas, which are already (as in the case of the concept of homology)
proving to be quite radical in their implications.
> P.S. What is your intellectual (or rather apologetic) goal in holding out
> against common ancestry, especially for that of humans with primates and
> other mammals (which is very recent)?
P.S.S. What is your intellectual (or rather apologetic) goal in holding out
for common ancestry, especially for that of humans with primates
and other mammals? ;-) Your motives, whatever they may be, are
no more relevant than mine. Let's stick to the evidence.
Best,
Paul Nelson
Senior Fellow
The Discovery Institute
www.discovery.org/crsc
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