On Tue, 17 Apr 2001 06:33:26 EDT RDehaan237@aol.com writes:
responding to Jon's message dated 4/15/01 9:06:58 PM,
jdac@alphalink.com.au :
>
> Thanks for your note. I agree that original research is a
> necessary. My
> wish is that more of it were done outside the evolutionary paradigm
> on
> problems that the paradigm should be able to solve, but hasn't. For
>
> instance, the idea that species go through the process of aging is
> not
> considered a respectable area of research in paleontology, since
> George
> Simpson squelched the topic in mid century by calling it an absurd
> idea. Yet
> there is significant evidence for it in the paleontological
> literature that,
> however, is consistently cast in an exclusively evolutionary
> framework, and
> thus lost. The concept of phyletic aging implies that phyletic
> groups go
> through a developmental process that involves the entire life cycle
> of the
> group and is independent of evolutionary processes. But I doubt if
> any
> evolutionary biologist or paleontologist would touch the topic.
>
> Phyletic development happens to be my pet anomaly. It raises doubts
> in my
> mind about the adequacy of Darwinian evolutionary theory. I would
> like to
> hear from others about anomalies they have regarding the theory.
> I'm not
> talking about shortcomings of the theories that will perhaps be
> resolved in
> time. I am talking about known phenomena that the theory should be
> able to
> and explain, but doesn't or can't. But what I read are largely
> criticisms of those who raise questions about the theory.
>
<snip>
>
> Regards,
>
> Bob
>
Senescence in species, especially, and to some extent in genera and
families, seems to me to be obviously explainable in evolutionary terms.
That organisms become better and better adapted to specific environments
seems to encompass a good deal of evolutionary theory. However, the
environment does not remain constant. I think of climate changes; plate
movements that bring separate land masses together and introduce new
competitors, predators, etc.; more subtle changes of various sorts which
a highly specialized group cannot cope with. This would look like
senescence in the fossil record, while fitting exactly into an
evolutionary pattern.
I've obviously painted with a broad brush. There are surely more subtle
matters which, if we could but recognize them across strata, would give a
a tighter evolutionary explanation. Then there are such matters as
genetic drift, which do not fit into the notion of becoming better
adapted. These are part of the total pattern. Put together (and since I
am looking on from outside, I believe there must be many other factors
that insiders can supply), there seems to me to be no dissonance between
"senescence" and evolutionary theory.
Dave
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