CREATIONISM IS CORRECT - Part 2
Date: Sat, 08 Apr 95 23:29:00 EDT
Subject: Creationism Is Correct (2/2)
CREATIONISM IS CORRECT - Part 2
"Science: Evolution Beetle that may explode the ideas of Darwin."
By Robert Matthews
(The Daily Telegraph)
(July 22, 1991; p.12)
"An insect that has undergone
three mutations cannot be the product of mere chance.
Robert Matthews asks whether it offers proof of a Creator."
Scuttling about in the undergrowth of Florida is a little beetle
which points up a controversial problem in modern biology. Called the
Bombardier beetle, it has a defence system that is little short of
miraculous. Indeed, "creationists" - who claim that God, not
evolution, is responsible for all living creatures - see this insect
as proof of their arguments. The Bombardier carries around inside its
body an explosive mixture of chemicals. Fortunately for the beetle,
they are normally prevented from going off by a chemical inhibitor.
But when the Bombardier is threatened, it injects another chemical -
an anti-inhibitor - into the mix. This triggers the manufacture of a
boiling-hot vapour of noxious gunk which the Bombardier sprays over
its attackers from a rotatable pipe built into its underside. The
scientific problem the Bombardier illustrates is that of creating such
a creature from random mutations of its genes, with natural selection
picking out the most useful mutations. Suppose, for example, that
millions of years ago one Bombardier underwent a mutation that enabled
it to make the explosive chemicals. Unless it was very lucky, it
would never live to try out its new-found capability. It would simply
explode. To survive, it needs a second mutation - to make the
inhibitor chemical. But a beetle with both these mutations is no
better off than one without the explosive chemicals. To enjoy any
benefit, the beetle needs a third mutation, this time to make the
anti-inhibitor. We are back to the exploding beetle problem. In short,
the Bombardier appears to demand that all the random mutations needed
for its amazing abilities occur at the same time. Yet given the rarity
of a single useful mutation occurring, the idea of many occurring
simultaneously stretches credulity to the limit. Creationists have a
ready answer - God. This eliminates the problem of simultaneous random
mutations; they are simply not involved. Scientists counter that the
answer may be that the Bombardier got some benefit from having just a
little of the explosive chemical, and this led it to survive long
enough to undergo other mutations. EVEN so, the beetle graphically
illustrates a nagging problem in biology: are mutations more than
simply random? In particular, are living creatures able to influence
mutations themselves, to ensure maximum benefit? In the latest issue
of the Proceedings of the National Academy of Sciences, Professor
Barry Hall of Rochester University, New York, publishes convincing
evidence for just such an ability. It seems that some unexplained
process may be directing mutations in living creatures.
This "heresy", that creatures can change genes in response to
changing environmental conditions to give their offspring a better
chance of survival, was propounded in the nineteenth century by the
French biologist Lamarck. But in this century it was rejected as part
of the modern synthesis called neo-Darwinism. Last year Hall caused a
stir when he came up with support for John Cairns and his colleagues
at the Harvard School of Public Health, who had published tentative
evidence for this process in 1988. Hall took a mutant strain of
bacteria unable to make a nutrient vital for its survival, and then
prevented them from getting the nutrient. He discovered that the
bacteria somehow forced themselves to mutate into a form which could
make the nutrient. This does not square too well with the idea of all
mutations being random. However, by depending on just one mutation,
the experiment left room to doubt that radical new thinking was
needed. Now Hall has forced the issue by new experiments in which the
bacteria have to undergo two mutations. If the probability of the
bacteria hitting just one mutation correctly is low, the chances of it
getting two right is minute. And yet he has found the same effect.
Hall calculates that if the results were due to chance, he would need
about 100 tonnes of bacteria to see just one bacterium change. In the
event, he reports seeing 37 independent bacteria undergo the double
mutations - exceeding the expectations of conventional theory by a
factor of 100 million. So far, the results have been restricted to
bacteria, and it is not clear yet whether the same process is at work
in more advanced creatures - such as the Bombardier beetle. However,
Hall does not rule it out, if only because he has no clear explanation
for what is going on in his Petri dishes. "Finding the mechanism is
clearly the highest priority at the moment," he said, admitting
frankly: "At this point, I'm groping around." Finding out what the
process is and controlling it could bring major benefits, Hall says.
"For example, cancer often involves multiple mutations, and
understanding the process that generates multiple mutations could
provide a major insight into this disease." Whatever its end uses, the
implications of a mutation-controlling force in living creatures
could, it is argued, trigger a revolution in biology. Views of this
sort put Hall rather out on a limb. An intriguing reaction comes from
Professor John Maynard Smith, the distinguished theoretical biologist
at Sussex University. He is not going to tear up his text books just
yet, but last week he ventured to say: "I really do think there's
something interesting going on. One does need to be a bit cautious, of
course. A cell has to have some way of knowing that it must fix a
certain mutation - otherwise it is magic!" In the United States, Hall
is, however, bracing himself for a backlash from conservative
biologists: "The old paradigm that says that mutations are absolutely
random with respect to their usefulness is dead - and that's going to
be hard for a lot of biologists to swallow."
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