Greetings --
It's odd that a discussion of "intelligent design" should come up on the paleo list,
since those most strongly favoring "intelligent design" also hold that the Earth is
only about 4,000 years old. "Intelligent design" theory is nothing but creationism in
scientific trappings. (I put it in quotes partly because it's actually a code
phrase, and partly because, from what I've seen of the design of the human body, if
it *was* designed, I'm not sure that "intelligent" is the word I'd use for some of
the arrangements.) What's odd about seeing it here is that it's completely
incompatible with any paleo paradigm.
A scientific theory is more than something which attempts to explain observations.
For something to genuinely be considered a scientific theory, it has to not only
explain all (or the vast majority) of observations it claims to explain, it must also
have predictive capabilities, that can be tested. Most importantly, the theory must
be disprovable using rational means of exploration. One can't either make
predictions based on divine creation, nor test them, nor prove or disprove the theory
with rational means of exploration. Hence, it's not a theory, it's simply religious
faith.
As for mutations being grist for the mill of adaptation, well, that's been documented
many times in single celled organisms, and in fact, there's a regular parade of
examples going on in bacteria which are developing antibiotic resistance. You can
demonstrate that process in the laboratory. It's a very simple experiment to run,
actually. You just take a bacterial culture that's genetically well defined, cloned
up from a single specimen, and expose the culture to an antibiotic at various
concentrations. You'll find that some of the bacteria have indeed had mutations that
led to new traits, mutations which can be identified, and then linked to changes in
protein form, etc. In fruit flies, numerous mutation/adaptation experiments have
been done (probably thousands) and have clearly showed that the same mechanism works
for multicellular organisms of considerable complexity. Notice, I'm not talking
about gene splicing, this is just natural selection in action.
What's true is that we can't *yet* test this theory prospectively for humans or
mammals for a variety of reasons. For one thing, because of the slow reproduction
rate (and other factors), you can't breed up a huge population of genetically
identical specimens. For another thing, mutations happen at relatively low rates (I
believe that it's about one mutation for every million DNA copy events) and you'd
need to experiment on huge populations for such artificial selection experiments.
Still, as cloning technology for mammals takes off, I'd expect to see such
experiments become feasible with mice in a decade or so.
Despite the difficulties with prospective testing of the theory in human beings,
however, the theory of evolution by random mutation and selective retention is
robust, has general applicability, and I believe has survived something like 13,000
attempts at disproof in a huge range of plant and animal experiments.
Ken Green
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