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The Five Crises in Evolutionary Theory
Dr. Ray Bohlin
The Case of the Missing Mechanism
The growing crisis in Darwinian theory is becoming more apparent all
the time. The work of creationists and other non-Darwinians is growing
and finding a more receptive ear than ever before. In this discussion I
want to elaborate on what I believe are the five critical areas where
Darwinism and evolutionary theory in general are failing. They are:
- The unsubstantiation of a Darwinian mechanism of evolution
- The total failure of origin of life studies to produce a workable
model
- The inability of evolutionary mechanism to explain the origin of
complex adaptations
- The bankruptcy of the blind watchmaker hypothesis
- The biological evidence that the rule in nature is morphological
stability over time and not constant change.
Much of the reason for evolution's privileged status has been due to
confusion over just what people mean when they use the word evolution.
Evolution is a slippery term. If evolution simply means "change
over time," this is non-controversial. Peppered moths, Hawaiian
drosophila fruit flies, and even Galapagos finches are clear examples of
change over time. If you say that this form of evolution is a fact,
well, so be it. But many scientists extrapolate beyond this meaning.
Because "change over time" is a fact, the argument goes, it is
also a fact that moths, fruit flies, and finches all evolved from a
remote common ancestor. But this begs the question.
The real question, however, is where do moths, flies, and finches
come from in the first place? Common examples of natural selection
acting on present genetic variation do not tell us how we have come to
have horses, wasps, and woodpeckers, and the enormous varieties of
living animals. Evolutionists will tell you that this is where mutations
enter the picture. But mutations do not improve the scenario either. In
speaking of all the mutation work done with bacteria over several
decades, the great French zoologist and evolutionist Pierre-Paul Grasse'
said:
What is the use of their unceasing mutations if they do not change? In
sum, the mutations of bacteria and viruses are merely hereditary
fluctuations around a median position; a swing to the right, a swing
to the left, but no final evolutionary effect.
When I speak of evolution or Darwinism, it is the origin of new
biological forms, new adaptive structures, morphological and biochemical
novelties that I am referring to. This is precisely what has not yet
been explained. When people question the popular explanations of the
origin of complex adaptations such as the vertebrate limb, or sexual
reproduction, or the tongue of the woodpecker, or the reptilian
hard-shelled egg, they are usually given a litany of reasons why these
structures are beneficial to the organisms. More precisely, the
selective advantage of these structures is offered as the reason they
evolved. But this begs the question again. It is not sufficient for an
evolutionist to explain the function of a particular structure. What is
necessary is to explain the mechanistic origin of these structures!
Natural selection does explain how organisms adapt to minor changes
in their environment. Natural selection allows organisms to do what God
commanded them to do. That is to be fruitful and multiply. Natural
selection does not, however, explain the crucial question of how complex
adaptations arose in the first place.
The Origin of Life
We have been led to believe that it is not to difficult to conceive
of a mechanism whereby organic molecules can be manufactured in a
primitive earth and organize themselves into a living, replicating cell.
In fact, the ease by which this can (allegedly) happen is the foundation
for the popular belief that there are numerous planets in the universe
which contain life. Nothing could be further from the truth.
Early experiments suggested that it was relatively simple to produce
some of the building blocks of life such as amino acids, the components
of proteins. However, the euphoria of the Miller- Urey experiment of
1953 has given way to a paradigm crisis of 1993 in origin of life
research. The wishful, yet workable atmosphere of ammonia, hydrogen,
methane, and water vapor has been replaced by the more realistic, but
stingy atmosphere of nitrogen, carbon dioxide, carbon monoxide, hydrogen
sulfide, and hydrogen cyanide. This is the stuff that volcanoes belch
out. This atmosphere poses a much more difficult challenge. Molecules
relevant for life would be much rarer. Even more damaging is the
possibility of the presence of molecular oxygen in the atmosphere from
the break-up of water vapor. Molecular oxygen would poison any reaction
leading to biologically significant molecules.
Coacervates, microspheres, the "RNA world," and other
scenarios all have serious flaws obvious to everyone in the field except
those who continue work with that particular scenario. Some have
privately called this predicament a paradigm crisis. There is no central
competing model, just numerous ego-driven scenarios. Even the
experiments in which researchers try to simulate the early earth have
been severely criticized. These experiments generally hedge their bets
by using purified reactants, isolated energy sources, exaggerated energy
levels, procedures which unrealistically drive the reaction toward the
desired product and protect the products from the destructive effects of
the energy sources which produced them in the first place.
The real situation was summed up rather well by Klaus Dose:
More than 30 years of experimentation on the origin of life in the
fields of chemical and molecular evolution have led to a better
perception of the immensity of the problem of the origin of life on
earth rather than to its solution. At present all discussions on
principal theories and experiments in the field either end in
stalemate or in a confession of ignorance." [From Interdisciplinary
Science Review 13(1988):348-56.]
But all of these difficulties together, as staggering as they are,
are not the real problem. The major difficulty in chemical evolution
scenarios is how to account for the informational code of DNA without
intelligence being a part of the equation. DNA carries the genetic code:
the genetic blueprint for constructing and maintaining a biological
organism. We often use the terms of language to describe DNA's activity:
DNA is "transcribed" into RNA; RNA is "translated"
into protein; geneticists speak of the "genetic code." All
these words imply intelligence, and the DNA informational code requires
intelligent preprogramming, yet a purely naturalistic beginning does not
provide such input. Chemical experiments may be able to construct small
sequences of nucleotides to form small molecules of DNA, but this
doesn't make them mean anything. There is no source for the
informational code in a strictly naturalistic origin of life.
The Inability to Account for Complex Adaptations
Perhaps the single greatest problem for evolutionary biologists is
the unsolved problem of morphological and biochemical novelty. In other
words, some aspects of evolutionary theory describe accurately how
existing organisms are well adapted to their environments, but do a very
poor job of explaining just how the necessary adaptive structures came
about in the first place.
Darwinian explanations of complex structures such as the eye and the
incredible tongue of the woodpecker fall far short of realistically
attempting to explain how these structures arose by mutation and natural
selection. The origin of the eye in particular, caused Darwin no small
problem. His only suggestion was to look at the variety of eyes in
nature, some more complex and versatile than others, and imagine a
gradual sequence leading from simple eyes to more complex eyes. However,
even the great Harvard evolutionist, Ernst Mayr, admits that the
different eyes in nature are not really related to each other in some
simple-to-complex sequence. Rather, he suggests that eyes probably had
to evolve over forty different times in nature. Darwin's nightmare has
never been solved. It has only been made 40 times more frightening for
the evolutionist.
In his 1987 book, Theories of Life, Wallace Arthur said:
One can argue that there is no direct evidence for a Darwinian origin
of a body plan--black Biston Betularia certainly do not
constitute one! Thus in the end we have to admit that we do not really
know how body plans originate.
In 1992, Keith Stewart Thomson wrote in the American Zoologist
that:
While the origins of major morphological novelties remain unsolved,
one can also view the stubborn persistence of macroevolutionary
questioning...as a challenge to orthodoxy: resistance to the view that
the synthetic theory tells us everything we need to know about
evolutionary processes.
The ability to explain major morphological novelties is not the only
failing of evolutionary theory. Some argue that molecular structures are
even more difficult to explain. The molecular architecture of the cell
has recently described by molecular biologist Michael Behe as being
irreducibly complex systems which must have all the components present
in order to be functional. The molecular workings of cilia, electron
transport, protein synthesis, and cellular targeting readily come to
mind. If the systems are irreducibly complex, how do they build slowly
over long periods of time out of systems that are originally doing
something else?
While publishing hundreds of articles pertaining to molecular
homology and phylogeny of various proteins and nucleic acids over the
last ten years, the Journal of Molecular Evolution did not
publish one article attempting to explain the origin of a single
biomolecular system. Those who make molecular evolution their life's
work are too busy studying the relationship of the cytochrome c molecule
in man to the cytochrome c molecule in bacteria, rather than the more
fundamental question of where cytochrome c came from in the first place!
Clearly then, whether we are talking about major morphological
novelties such as the wings of bats and birds, the swimming adaptations
of fish and whales, the human eye or the molecular sub- microscopic
workings of mitochondria, ribosomes, or cilia, evolutionary theory has
failed to explain how these structures could arise by natural processes
alone.
The Bankruptcy of the Blind Watchmaker Hypothesis
In his 1986 book, The Blind Watchmaker, Richard Dawkins
states, "Biology is the study of complicated things that give the
appearance of having been designed for a purpose." He explains that
Natural selection is the blind watchmaker, blind because it does not
see ahead, does not plan consequences, has no purposes in view. Yet
the living results of natural selection overwhelmingly impress us with
the appearance of design as if by a master watchmaker, impress us with
the illusion of design and planning.
Darwinism critic, Philip Johnson, has quipped that the watchmaker is
not only blind but unconscious!
Dawkins later suggests just how this process may have brought about
the development of wings in mammals. He says:
How did wings get their start? Many animals leap from bough to bough,
and sometimes fall to the ground. Especially in a small animal, the
whole body surface catches the air and assists the leap, or breaks the
fall, by acting as a crude aerofoil. Any tendency to increase the
ratio of surface area to weight would help, for example flaps of skin
growing out in the angles of joints...(It) doesn't matter how small
and unwinglike the first wingflaps were. There must be some height,
call it h, such that an animal would just break its neck if it fell
from that height. In this critical zone, any improvement in the body
surface's ability to catch the air and break the fall, however slight
the improvement, can make the difference between life and death.
Natural selection will then favor slight, prototype wingflaps. When
these flaps have become the norm, the critical height h will become
slightly greater. Now a slight further increase in the wingflaps will
make the difference between life and death. And so on, until we have
proper wings.
This can sound rather seductively convincing at first. However there
are three faulty assumptions being used.
The first doubtful assumption is that nature can provide a whole
chain of favorable mutations of the precise kind needed to change
forelimbs into wings in a continuous line of development. What is the
larger miracle, an instantaneous change or a whole series of thousands
of tiny changes in the proper sequence?
The other assumption is "all things being equal." These
mutations must not have secondary harmful effects. How is the creature's
grasping ability compromised while these wingflaps grow? These little
shrew-like animals may slowly be caught between losing their
adaptiveness in the trees before they can fully utilize their
"developing" wings. Or there might be some seemingly unrelated
and unforeseen effect that compromises survivability.
A third faulty assumption is the often used analogy to artificial
selection. "If artificial selection can do so much in only a few
years," so the refrain goes, "just think what natural
selection can do in millions of years." But artificial selection
works because it incorporates foresight and conscious purpose, the
absence of which are the defining qualities of the blind watchmaker. In
addition, artificial selection actually demonstrates the limits to
change since an endpoint in the selection process is usually reached
very quickly.
The blind watchmaker hypothesis, when analyzed carefully, falls into
the category of fanciful stories that are entertaining--but which hold
no resemblance to reality.
The Prevalence of Stasis over Mutability
Rather than observing organisms gradually evolving into other forms,
the fossil record speaks of "sudden appearance" and
"stasis." New types appear suddenly and change very little
after their appearance. The rarity of gradual change examples in the
fossil record were revealed as the trade secret of paleontology by
Steven J. Gould of Harvard. Gould also refers to stasis as
"data" in the paleontological sense. These are significant
observations.
Darwin predicted that there should be innumerable transitional forms
between species. But the reality of paleontology (the study of fossils)
is that new forms appear suddenly with no hint of the
"gradual" change predicted by evolution. Not only that, but
once these new forms have appeared, they remain relatively unchanged
until the present day or until they become extinct.
Some animals and plants have remained unchanged for literally
hundreds of millions of years. These "living fossils" can be
more embarrassing for the evolutionist than they often care to admit.
One creature in particular, the coelacanth, is very instructive. The
first live coelacanth was found off the coast of Madagascar in 1938.
Coelacanths were thought to be extinct for 100 million years. But most
evolutionists saw this discovery as a great opportunity to glimpse the
workings of a tetrapod ancestor. Coelacanths resemble the proposed
ancestors of amphibians. It was hoped that some clues could be derived
from the modern coelacanth of just how a fish became preadapted for life
on land, because not only was there a complete skeleton, but a full set
of internal organs to boot. The results of the study were very
disappointing. The modern coelacanth showed no evidence of internal
organs preadapted for use in a terrestrial environment. The coelacanth
is a fish--nothing more, nothing less. Its bony fins are used as
exceptionally well-designed paddles for changing direction in deep-sea
environment, not the proto-limbs of future amphibians.
Nowhere is the problem of sudden appearance better demonstrated than
in the Burgess Shale found in the Canadian Rockies. The Burgess Shale
illustrates that in the Cambrian period (which evolutionists estimate as
being over 500 million years ago) nearly all of the basic body plans
(phyla) of animals existing on earth came into existence in a geological
instant (defined as only 20-30 million years), and nothing that new has
appeared since that time. The Cambrian explosion as it is called is
nothing less than astounding. Sponges, jellyfish, worms, arthropods,
mollusks, echinoderms, and many other stranger-than-fiction creatures
are all found to suddenly appear in the Cambrian without a hint of what
they descended from nor even how they could all be related to each
other. This is the opposite expectation of Darwinism which would have
predicted each new body plan emerging from pre-existing phyla over long
periods of time. The Cambrian explosion is a direct contradiction of
Darwinian evolution.
If Darwin were alive today, I believe he would be terribly
disappointed. There is less evidence for his theory now than in his own
day. The possibility of the human eye evolving may have caused him to
shudder, but the organization of the simplest cell is infinitely more
complex. Perhaps a nervous breakdown would be more appropriate!
© 1993 Probe Ministries
About the Author
Raymond
G. Bohlin is executive director of Probe Ministries. He is a
graduate of the University of Illinois (B.S., zoology), North Texas
State University (M.S., population genetics), and the University of
Texas at Dallas (M.S., Ph.D., molecular biology). He is the co-author of
the book The Natural Limits to Biological Change, served as
general editor of Creation, Evolution and Modern Science, and has
published numerous journal articles. Dr. Bohlin was named a 1997-98 and
2000 Research Fellow of the Discovery Institute's Center for the Renewal
of Science and Culture. He can be reached via e-mail at rbohlin@probe.org.
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