The Evolution of the Flagellum And the Climbing of Mt ImprobableSean D. Pitman M.D. May 2006Last Updated August 2010, ...
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The Evolution of the
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And the Climbing of "Mt. Improbable "
Dr. Sean DeVere Pitman, M.D.
Loma Linda University School of Medicine, 1993 - 1997
Major, United States Army, active duty 1997 - 2001
Residency: Pathology, Loma Linda University Medical Center, 2001 - 2005
Fellowship: Hematology, City of Hope National Medical Center, 2005 - 2006
Email:
Sean D. Pitman, M.D.
© May 2006
Last Updated: August 2010
Table of Contents
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Point Mutations vs. Non-Homologous
Crossover Mutations?
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The Appearance of Design
Most modern scientists believe that all living things, with all of their various parts and systems
of function, evolved through a process of random mutation and natural selection from a common
ancestor life form over the course of hundreds of millions of years of time. Of course, Darwin's
famous observations and documentations of various real time changes in many different creatures,
such as the fairly striking differences in finches in different regions, helped to popularize this
concept (
. Since then, the interpretations of the
and th
along with
many modern examples of real time evolution, such as the rapid evolution of
in
bacteria, only seem to confirm the theory of evolution as something, "more than a theory". <?
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Still, there are some who continue to question the creative potential of such a mindless
process. Can the seemingly simplistic mechanism of random mutation and natural selection really
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give rise to the amazing complexity and diversity of all living things? For many, the wonders of the
natural world and universe, especially when it comes to living things, are so awe inspiring that they
intuitively appear as though they were deliberately set in place by an extraordinary brilliant
intelligence - even a God or at least godlike intelligence.
Consider an observation from
Keiichi Namba (program director of a team of dedicated scientists working to detail
the various steps in flagellar assembly):
"An enormous number of those
macromolecules play each role just like
purposefully designed machines and
maintain the complex network activities."
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The counter argument is, of course, that though grand the universe and all living things only
have the "
appearance
of design" when, in reality, no deliberate foresight or planning went into their
creation. How is this mindless non-directed creation accomplished? Through the creative powers of
random mutation and natural selection. (
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The Evolutionary Mechanism
The question is, of course, can a mindless non-directed process that has absolutely no goal or
higher purpose in mind, really produce the wonders that we see all around us and even within our
own selves? We are told by popular science that it is all about "baby steps" - the little differences
and changes that add up over time to produce fantastic variation in form and function. Clearly, if
little changes could be selected in a positive way over time they could obviously add up to produce
bigger and bigger changes until all the diversity and functional complexity that we see today is the
end result - the result of billions of years of tiny modifications in many diverging and even
converging family trees.
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