On Tue, 30 Jun 1998 22:24:03 -0500, Glenn R. Morton wrote:
[...]
GM>It seems to me that the common design argument fails when one
>is forced to believe that the Designer designed broken parts.
[...]
Firstly, as so often happens with evolutionary claims, Glenn
attempts to win the argument by using loaded words like "broken
parts". A pseudogene does not have to be regarded as a "broken
part". It can be looked at from an Intelligent Design perspective as
the genetic analogy of a switch that has purposefully been turned off.
Secondly, it is not clear that a pseudogene was "broken" (to use
Glenn's pejorative term) at the beginning. Kimura points out that in
the case of vitamin C, the accumulation of neutral mutations may not
have been shielded by natural selection when the animal is already
eating a vitamin C rich diet:
"As an interesting example of evolutionary degeneration of
characters, I would like to take the loss of ascorbic acid synthesizing
ability in man and a few other species. Recently, Jukes and King
(Jukes TH and King JL: J Human Evolution 4: 85, 1975) theorized
that this loss had occurred as a neutral evolutionary change.
According to them, the ability to synthesize ascorbic acid (vitamin C)
is in general a characteristic of terrestrial vertebrates. However,
besides the human, the ability is not present in monkeys, guinea pigs,
fruit-eating bats and some passerine birds. These animals consume
food rich in ascorbic acid, and it is assumed that the mutants leading
to loss of the synthesizing ability were neutral and became fixed in the
species through random gene frequency drift. The alternative
hypothesis is that the loss was adaptive, and occurred by positive
natural selection. Jukes and King's hypothesis appears to be more
plausible since many herbivorous vertebrate species, which consume
food high in ascorbic acid, have retained the ability to synthesize it.
The observation that the loss occurred in species that are widely
scattered in phylogeny also supports their hypothesis." (Kimura M.,
"Population Genetics and Molecular Evolution," The Johns Hopkins
Medical Journal, Vol. 138, No. 6, June 1976, p260)
So, even though I don't necessarily hold this, if Adam had been
created de novo ca. 50,000 years ago with the ability to synthesise
vitamin C, it is entirely possible that somewhere between then and
now, because his descendants were eating a vitamin C-rich diet, their
ability to synthesis vitamin C was lost. The argument that humans
today have a vitamin C pseudogene does not necessarily mean
that humans at the beginning had it and so it can't be advanced
as a compelling anti-design argument.
Thirdly, as I have pointed out previously, this is just another example
of what Johnson calls the "God-wouldn't-have-done-it-that-way"
fallacy.
"Douglas Futuyma also leans heavily on the "God wouldn't have done
it" theme, citing examples from vertebrate embryology:
`Why should species that ultimately develop adaptations for utterly
different ways of life be nearly indistinguishable in their early stages?
How does God's plan for humans and sharks require them to have
almost identical embryos? Why should terrestrial salamanders, if they
were not descended from aquatic ancestors, go through a larval stage
entirely within the egg, with gills and fins that are never used, and
then lose these features before they hatch?' (Futuyma D., "Science on
Trial: The Case for Evolution," 1983, p48)
These are rhetorical questions, but they point to legitimate starting
points for investigation. The features Futuyma cites may exist
because a Creator employed them for some inscrutable purpose; or
they may reflect inheritance from specific common ancestors; or they
may be due to some as yet unimagined process which science may
discover in the future. The task of science is not to speculate about
why God might have done things this way, but to see if a material
cause can be established by empirical investigation." (Johnson P.E.,
"Darwin on Trial," 1993, pp70-71)
There is no reason that I can think of why an omniscient Intelligent
Designer would not create new designs by modifying old ones, which
included some genes that had been switched off after they had served
an earlier purpose.
In the case of the vitamin C pseudogene in primates, there is a very
good reason why that gene was not switched back on. The fact that
man cannot synthesise his own vitamin C has probably been an
important factor in ensuring man developed agriculture and culture.
The "God-wouldn't-have-done-it-that-way" anti-design theorists
should pause and consider what the Apostle Paul said about "...the
foolishness of God is wiser than man's wisdom...." (1Cor 1:25)
Steve
"Evolution is the greatest engine of atheism ever invented."
--- Dr. William Provine, Professor of History and Biology, Cornell University.
http://fp.bio.utk.edu/darwin/1998/slides_view/Slide_7.html
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Perth, West Australia v "Test everything." (1Thess 5:21)
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