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). |