evolution as scientific methodlogy

[Curtis Clark]

At 01:19 PM 8/15/99 -0400, John Grehan wrote:
>I think the predictions about similarities and differences as yet
>unknown may refer to methodology. So what predictions are generated
>through what evolutionary methods?

The principle of common descent suggests that any two organisms share a
body of similarities that have a single cause (their descent). This
provides a hypothesis that other similarities have the same cause. For each
similarity, that hypothesis can be falsified or supported. If it is
supported, no additional cause need be sought or asserted for the
similarity.

If species are created separately, similarity might be taken as
unapproachable in the context of science ("God made it, I believe it, that
settles it"). Some natural theologians instead took the view that God's
intelligence could be seen in features as adaptations; in that context,
although all similarities had the same ultimate cause (God), each
similarity could have a different proximate cause (a specific adaptation).

>It seems to me that definitial approaches to speciation such as
>the mate recognition concept, the biological species concept,
>phylogenetic species concept, try to do the same thing. They
>all look to an essential kind of variation that separates the species,
>and other variation that does not ("accidental"?)

Typological thinking predates even Christianity (although it was adopted by
the Church in the Middle Ages). IMHO it is indefensible, and I've certainly
worked to expunge it from my own science. I won't address it further except
to say that I have yet to see a creationist account of biology that wasn't
typological.

>I cannot speak authoritatively on behalf of creationists, but my limited
>understanding is that they could view the existence of some similarities
>as an indicator that there should be others if they view biological form
>as the expression of a particular plan of biological organization. In
>which case there is really no methodological difference here.

Creationists can't test the plan, because it can't be falsified.

>>Evolution provides the rational for the distribution of characters. Study
>>of variation in an evolutionary context has most often reinforced the
>>hypothesis that all organisms are kin.
>
>This does not describe evolution as a scientific methodology. It is one
>possible comparison of philosophical frameworks.

I think you are nit-picking here. Every methodology has a philosophical
framework. If one assumes descent with modification, the set of questions
that are asked is different from the set asked by someone who assumes
independent creation. Maybe I don't understand your use of the word
"methodology".

>The studies referred to may require an evolutionary framework, but what
>about them if anything makes them an evolutionary research program
>as opposed to research programs that are simply given an evolutionary
>interpretation?

I think you are missing a very big point here: these research programs
wouldn't even exist in a creationist context, because they would make no
sense. The research in chemistry done by those who supported phlogiston was
necessarily aimed in a different direction than later works that accepted
the existence of oxygen, and quantum chromodynamics would not be possible
in a science that accepted atoms as indivisible. To the extent that work by
current creationists can be characterized as scientific research, it seeks
to answer things that evolutionists would characterize as "non-questions",
and the creationists characterize evolutionary research in the same way.

>I am one of the few people, I think, who do not care whether creation is
>science
>or not,

But it can be, and it was. The biology of the 18th and most of the 19th
century was done by creationists, and we routinely honor them, at least in
history chapters, for their accomplishments. Like most plant taxonomists, I
can trace my academic "parentage" back to Linnaeus. I think he was totally
on the wrong track, but that doesn't mean he wasn't doing science.

And I think it is an indication of just how slowly ideas change that it
took nearly a century between Darwin and Hennig.

 Instead, I am interested in
>which
>research programs are progressive and which are regressive. Since
>creation science is simply a reiteration of an assertion (creation) it
>appears
>to be regressive. However, some evolutionary perspecitves also seem to
>be regressive in this regard as well.

I wonder if you're not using this discussion as a dig at *specific*
perspectives that you see as regressive. I'm sure we all put stuff in that
category, but I think it is a mistake (and a common one) to judge a
viewpoint by the competence of the people who espouse it.


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Curtis Clark                  http://www.csupomona.edu/~jcclark/
Biological Sciences Department             Voice: (909) 869-4062
California State Polytechnic University      FAX: (909) 869-4078
Pomona CA 91768-4032  USA                  jcclark at csupomona.edu