Evolution: Rationality vs. Randomness


An M.I.T. physicist takes a look at Darwin, the fossil record, and the likelihood of random evolution.

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. With nature doing the selection, evolutionists claim to remove the theory of evolution from that of a random process. We are told that 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 mutations from among which the selection by survival takes place.

The question is: Can random mutations produce the evolution of life?

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,” and environmental conditions—all these affect the rate and direction of the changes in morphology. And these are all unknowns.

From a secular view, 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. The challenges presented by the environment determine which will survive to produce the new generations and which will perish.


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 an event recorded in the fossil record and known as the Cambrian explosion of animal life, some 50 phyla (basic body plans) suddenly and simultaneously appeared in the fossil record. This is the first appearance of complex animal life. Only 30 to 34 of the phyla survived. The rest perished. Since then the fossil record and modern existing biota reveal that no new phyla have evolved. At a later stage in the flow of life, a catastrophic event (possibly the collision of the earth with a massive comet or meteor) eliminated 90% of all life forms. The ecology was wide open for new phyla to develop. Again, no new phyla appear. The implication is that only a limited number of life forms (phyla) are viable.

It is no wonder that the most widely read science journal, Scientific American, asked “has the mechanism of evolution altered in ways that prevent fundamental changes in body plans of animals” (November 1992). It is not that the mechanism of evolution has changed; it is our understanding of how evolution functions that must change to fit the data presented by the fossil record and by the discoveries of molecular biology.

It is difficult and painful to discard entrenched notions of what is actually true, even when scientific data demand such an abandonment. Pure randomness as the source of the mutations that neo-Darwinian concepts demand to drive the evolution of life no longer stands against the mounting evidence of scientific data. Unfortunately, the emotional commitment to a totally materialist view of life makes discarding this notion problematic.

Let’s look at the likelihood that random mutations could have produced viable forms of life. Life as we know it is built largely of combinations of proteins working in symbiotic harmony. But as we’ve seen, only certain combinations produce viable life. Other combinations fail.

Humans and all mammals have some 50,000 genes. That implies, as an order of magnitude estimate, some 50,000 to 100,000 proteins active in mammalian bodies. It is estimated that there are some 30 animal phyla on Earth. If the genomes of each animal phylum produced 100,000 proteins, and no proteins were common among any of the phyla (a fact we know to be false, but an assumption that makes our calculations favor the random evolutionary assumption), there would be (30 x 100,000) 3 million proteins in all life. (The actual number is vastly lower.)

Now let’s consider the likelihood of these 3 million viable combinations of proteins forming by chance, recalling that the events following the Cambrian explosion of animal life and the later decimation of 90% of life taught us that only certain combinations of proteins are viable.

Proteins are complex coils of several hundred amino acids. Take a typical protein to be a chain of 200 amino acids. The observed range is from less than 100 amino acids per protein to greater than 1000. There are 20 commonly occurring amino acids that join in varying combinations to produce the proteins of life. This means that the number of possible combinations of the amino acids in our model protein of 200 amino acids is 20 to the power of 200 (i.e. 20 multiplied by itself 200 times), or in the more usual 10-based system of numbers, approximately 10 to the power of 260 (i.e. the number one, followed by 260 zeros!). Nature has the option of choosing among the 10 to power of 260 possible proteins, the 3 million proteins of which all viable life is composed. In other words, for each one correct choice, there are 10 to power of 254 wrong choices!

Simon Conway Morris, professor of evolutionary paleontology at the University of Cambridge and fellow of the Royal Society of England, is the scientist who revealed the significance of the Cambrian explosion of animal life. He refers to this vast biological waste land of failed life forms as the “multidimensional hyperspace of biological reality.”

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 non-viable proteins—and pulled out the one that worked.

And then repeated this trick a million times.

With odds like that, it is amazing that nature and our bodies ever got it or get it right.

But perhaps not every amino acid can join with every other amino acid. If this is the case, then the number of possible combinations will be reduced. To get even hint for what this would do to the hyperspace of failed choices, I looked at combinations of amino acids that actually exist in just six proteins. Among the proteins I used were bovine insulin and bovine ribonuclease. The number of potential amino acid combinations just from this modest sampling of proteins was 10 to the power of 20. Again, nature would have had to select the one viable combination from among 100 billion billion wrong choices. Either our knowledge of statistical probability is skewed or something other than randomness is operating.

The late Harvard professor, Stephen Jay Gould, suggested that the flow of life is “channeled” along these basic animal phyla.

Nobel laureate, organic chemist and a leader in origin of life studies, Professor deDuve writes in his excellent book, Tour of a Living Cell, “If you equate the probability of the birth of a bacteria cell to chance assembly of its atoms, eternity will not suffice to produce one… Faced with the enormous sum of lucky draws behind the success of the evolutionary game, one may legitimately wonder to what extent this success is actually written into the fabric of the universe.” Life written into the fabric of the universe sounds a bit metaphysical.

Morris, in his book Life’s Solutions (Cambridge University Press, 2003), writes: “Life is simply too complex to be assembled on any believable time scale… evolution’s uncanny ability to find the short cuts across the multidimensional hyperspace of biological reality. It is my suspicion that research might reveal a deeper fabric to biology…” Elsewhere Morris identifies this “deeper fabric” as having “metaphysical implications.”

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, such gibberish was and is lethal.

In brief, randomness cannot have been the driving force behind the success of life. Our understanding of statistics and molecular biology clearly supports the notion that there must have been a direction and a Director behind the success of life.

Has Science Discovered God?


by  Dr. Gerald Schroeder
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