evolution as scientific methodlogy

[Curtis Clark]

Here is my original post, which I had sent to John:

At 05:14 PM 8/14/99 -0400, Joh Grehan wrote:
>With respect to the current postings on evolution and creation theory I
>have
> a question that I would like to pose. What examples would
>people present to delinate evolutionary theory as scientific methodology?
>This question is different from what people do to "prove" evolution. I am
>interested to know what kind of research activities evolutionary theory
>results in that would be impossible with a creation perspective, and how
>these activities lead to new empirical insights (again, that a creationist
>would not be able to make whether a geneticist, morphologist, ecologist,
>biogeographer, systematist).

All of comparative biology. Evolution provides a causation for the
similarities among organisms, as well as a causation for their differences.
And evolution makes predictions about similarities and differences as yet
unknown.

I look to Linnaeus as an example of a truly scientific creationist. He
understood that the variation within originally created species (what we
translate as "accidental variation") must be of a fundamentally different
nature that the "essential variation" that separated the species. Essential
variation was a record of the original creation, whereas accidental
variation, both theologically and biologically, was the result of
subsequent deviation from type. The importance to the biologists of his era
of distinguishing the two types of variation cannot be overstated; if we
were all still creationists today, we'd be bringing the whole arsenal to
bear on it (and IMHO failing :-).

If one accepts that all organisms are kin (based on the copious evidence of
that), the two types of variation are effectively united. To a comparative
biologist working in an evolutionary framework, the existence of
similarities between two species suggests that there will be other
similarities. To a creationist, all similarities among species are the
result of a single imponderable event outside the scope of scientific
inquiry, so the existence of some similarities between any two species is
no sure indicator that there should be others.

Admittedly, a study of essential variation should lead a creationist closer
to understanding the "mind of God" when he created the species, and I
accept that as a legitimate scientific endeavor. But the species are a
"fait accompli", and even if we decide that God had no interest in putting
feathers on mammals or creating flowering plants with siphonosteles, and
that he had an inordinate fondness for hierarchies, we are as clueless as
ever about what to do with this information.

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.

An off-the-top-of-my-head list of biological studies that *require* an
evolutionary framework:

* endosymbiosis (why did God create chloroplasts and mitochondria with
bacterial genes?)
* biogeography (the distribution of each *created* species must be studied
individually; in the case of vicariance, it *must* be established whether
the vicariants are separate species or the same)
* genetic engineering, especially transgenics (No a priori basis to assume
that genes artificially transfered between species will behave in the same
way as those transfered within)
* animal models in biomedicine (who among creationists would have ever
expected that chimps and only chimps could be infected with HIV?)

I think the reason "defenders of evolution" don't emphasize the scientific
methodology is that, even though it totally permeates modern biology, most
biologists are blind to it. I agree with you (I think) that this is not a
good thing.

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Curtis Clark                  http://www.csupomona.edu/~jcclark/
Biological Sciences Department             Voice: (909) 869-4062
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