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At the
basis of the theory of neo-Darwinian evolution lie two basic assumptions:
That changes in morphologies are induced by random mutations on the
genome; and, that these changes in the morphology of plant or animal
make the life form either more or less successful in the competition
to survive. It is by the aspect of nature's selection that evolutionists
claim to remove the theory of evolution from that of a random process.
The selection is in no way random. It is a function of the environment.
The randomness however remains as the basic driving force that produces
the varied morphologies behind the selection. Can random
mutations produce the evolution of life? That is the question addressed
herein. Because
evolution is primarily a study of the history of life, statistical analyses
of evolution are plagued by having to assume the many conditions that
were extant during those long gone eras. Rates of mutations, the contents
of the "original DNA, " the environmental conditions, all
effect the rate and direction of the changes in morphology and are all
unknowns. One must never ask what the likelihood is that a specific
set of mutations will occur to produce a specific animal. This would
imply a direction to evolution and basic to all Darwinian theories of
evolution is the assumption that evolution has no direction. The induced
changes, and hence the new morphologies, are totally random, regardless
of the challenges presented by the environment. With this
background, let's look at the process of evolution. Life is in essence
a symbiotic combination of proteins (and other structures, but here
I'll discuss only the proteins). The history of life teaches us that
not all combinations of proteins are viable. At the Cambrian explosion
of animal life, 530 million years ago, some 50 phyla (basic body plans)
appeared suddenly in the fossil record. Only 30 to 34 survived. The
rest perished. Since then no new phyla have evolved. It is no wonder
that Scientific American asked whether the mechanism of evolution has
changed in a way that prohibits all other body phyla. It is not that
the mechanism of evolution has changed. It is our understanding of how
evolution functions that must change, change to fit the data presented
by the fossil record. To use the word of Harvard professor Stephen Jay
Gould, it appears that the flow of life is "channeled" along
these 34 basic directions. Let's
look at this channeling and decide whether or not it can be the result
of random processes. Humans
and all mammals have some 50,000 genes. That implies we have, as an
order of magnitude estimate, some 50,000 proteins. It is estimated that
there are some 30 million species of animal life on Earth. If the genomes
of all animals produced 50,000 proteins, and no proteins were common
among any of the species (a fact we know to be false, but an assumption
that makes our calculations favor the random evolutionary assumption),
there would be (30 million x 50,000) 1.5 trillion (1.5 x 1012
) proteins in all life. (The actual number is vastly lower). Now let's
consider the likelihood of these viable combinations of proteins forming
by chance, recalling that, as the events following the Cambrian explosion
taught us, not all combinations of proteins are viable. Proteins
are coils of several hundred amino acids. Take a typical protein to
be a chain of 300 amino acids. There are 20 commonly occurring amino
acids in life. This means that the number of possible combinations of
the amino acids in our model protein is 20300 or in the more
usual ten-based system of numbers, 10390 . Nature has the
option of choosing among the possible 10390 proteins, the
1.5 x 1012 proteins of which all viable life is composed.
Can this have happened by random mutations of the genome? Not if our
understanding of statistics is correct. It would be as if nature reached
into a grab bag containing a billion billion billion billion billion
billion billion billion billion billion billion billion billion billion
billion billion billion billion billion billion billion billion billion
billion billion billion billion billion billion billion billion billion
billion billion billion billion billion billion billion billion billion
billion proteins and pulled out the one that worked and then repeated
this trick a million million times. But this
impossibility of randomness producing order is not different from the
attempt to produce Shakespeare or any meaningful string of letters more
than a few words in length by a random letter generator. Gibberish is
always the result. This is simply because the number of meaningless
letter combinations vastly exceeds the number of meaningful combinations.
With life it was and is lethal gibberish. Nature,
molecular biology and the Cambrian explosion of animal life have given
us the opportunity to study rigorously the potential for randomness
as a source of development in evolution. If the fossil record is an
accurate description of the flow of life, then the34 basic body plans
that burst into being at the Cambrian, 530 million years ago, comprise
all of animal life till today. The tree of life which envisioned a gradual
progression of phyla from simple forms such as sponges, on to more complex
life such as worms and then on to shelled creatures such as mollusks
has been replaced by the bush of life in which sponges and worms and
mollusks and all the other of the 34 phyla appeared simultaneously.
Each of these bush lines then developed (evolved) a myriad of variations,
but the variations always remained within the basic body plan. Among
the structures that appeared in the Cambrian were limbs, claws, eyes
with optically perfect lenses, intestines. These exploded into being
with no underlying hint in the fossil record that they were coming.
Below them in the rock strata (i.e., older than them) are fossils of
one-celled bacteria, algae, protozoans, and clumps known as the essentially
structureless Ediacaran fossils of uncertain identity. How such complexities
could form suddenly by random processes is an unanswered question. It
is no wonder that Darwin himself, at seven locations in The Origin of
Species, urged the reader to ignore the fossil record if he or she wanted
to believe his theory. Abrupt morphological changes are contrary to
Darwin's oft repeated statement that nature does not make jumps. Darwin
based his theory on animal husbandry rather than fossils. If in a few
generations of selective breeding a farmer could produce a robust sheep
from a skinny one, then, Darwin reasoned, in a few million or billion
generations a sponge might evolve into an ape. The fossil record did
not then nor does it now support this theory. The abrupt
appearance in the fossil record of new species is so common that the
journal Science, the bastion of pure scientific thinking, featured the
title, "Did Darwin get it all right?" And answered the question:
no. The appearance of wings is a classic example. There is no hint in
the fossil record that wings are about to come into existence. And they
do, fully formed. We may have to change our concept of evolution to
accommodate a reality that the development of life has within it something
exotic at work, some process totally unexpected that produces these
sudden developments. The change in paradigm would be similar to the
era in physics when classical logical Newtonian physics was modified
by the totally illogical (illogical by human standards of logic) phenomena
observed in quantum physics, including the quantized, stepwise changes
in the emission of radiation by a body even as the temperature of the
body increases smoothly. With the
advent of molecular biology's ability to discern the structure of proteins
and genes, statistical comparison of the similarity of these structures
among animals has become possible. The gene that controls the development
of the eye is the same in all mammals. That is not surprising. The fossil
record implies a common branch for all mammals. But what is surprising,
even astounding, is the similarity of the mammal gene tthe gene that
controls the development of eyes in mollusks and the visual systems
in worms. The same can be said for the gene that controls the expression
of limbs in insects and in humans. In fact so similar is this gene,
that pieces of the mammalian gene, when spliced into a fruit fly, will
cause a wing to appear on the fly. This would make sense if life's development
were described as a tree. But the bush of life means that just above
the level of one-celled life, insects and mammals and worms and mollusks
separated. The eye
gene has 130 sites. That means there are 20130 possible combinations
of amino acids along those 130 sites. Somehow nature has selected the
same combination of amino acids for all visual systems in all animals.
That fidelity could not have happened by chance. It must have been pre-programmed
in lower forms of life. But those lower forms of life, one-celled, did
not have eyes. These data have confounded the classic theory of random,
independent evolution producing these convergent structures. So totally
unsuspected by classical theories of evolution is this similarity that
the most prestigious peer-reviewed scientific journal in the Untied
States, Science, reported: "The hypothesis that the eye of the
cephalopod [mollusk] has evolved by convergence with vertebrate [human]
eye is challenged by our recent findings of the Pax-6 [gene] ... The
concept that the eyes of invertebrates have evolved completely independently
from the vertebrate eye has to be reexamined." The significance
of this statement must not be lost. We are being asked to reexamine
the idea that evolution is a free agent. The convergence, the similarity
of these genes, is so great that it could not, it did not, happen by
chance random reactions. The British
Natural History Museum in London has an entire wing devoted to the evolution
of species. And what evolution do they demonstrate? Pink daisies evolving
into blue daisies; small dogs evolving into big dogs; a few species
of cichlid fish evolving in a mere few thousand years into a dozen species
of cichlid fish. Very impressive. Until you realize that the daisies
remained daisies, the dogs remained dogs and the cichlid fish remained
cichlid. It is called micro-evolution. This magnificent museum, with
all its resources, could not produce a single example of one phylum
evolving into another. It is the mechanisms of macro-evolution, the
change of one phylum or class of animal into another that has been called
into question by these data. The reality of this explosion of life was discovered long before it was revealed. In 1909, Charles D. Walcott, while searching for fossils in the Canadian Rocky Mountains, came upon a strata of shale near the Burgess Pass, rich in that for which he had been seeking., fossils from the era known as the Cambrian. Over the following four years Walcott collected between 60,000 and 80,000 fossils from the Burgess Shale. These fossils contained representatives from every phylum except one of the phyla that exist today. Walcott recorded his findings meticulously in his notebooks. No new phyla ever evolved after the Cambrian explosion. These fossils could have changed the entire concept of evolution from a tree of life to a bush of life. And they did, but not in 1909. Walcott knew he had discovered something very important. That is why he collected the vast number of samples. But he could not believe that evolution could have occurred in such a burst of life forms, "simultaneously" to use the words of Scientific American. This was totally against the theory of Darwin in which he and his colleagues were steeped. And so Walcott reburied the fossil, all 60,000 of them, this time in the draws of his laboratory. Walcott was the director of the Smithsonian Institute in Washington D.C. It was not until 1985 that they were rediscovered (in the draws of the Smithsonian). Had Walcott wanted, he could have hired a phalanx of graduate students to work on the fossils. But he chose not to rock the boat of evolution. Today fossil representatives of the Cambrian era have been found in China, Africa, the British Isles, Sweden, Greenland. The explosion was worldwide. But before it became proper to discuss the extraordinary nature of the explosion, the data were simply not reported. It is a classic example of cognitive dissonance, but an example for which we have all paid a severe price.
At this
point we must ask the question, what has produced the wonders of life
that surround us? The answer may be implied by those very surroundings.
In that case the medium would be the message! Gerald Schroeder has his BSc MSc and PhD (Earth and Planetary Sciences; and, Nuclear Physics) all from the Massachusetts Institute of Technology where he taught physics for seven years. He is the author of Genesis and the Big Bang (Bantam Doubleday) and The Science of God (Free Press; Simon & Schuster). |