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Evidence from Molecular Biology
Minimum Requirements for Self-Reproducing Cell
Interdependent Molecular Functions
The Fallacy of Homologous Structures
(The purpose of this page is to present evidence from the field of molecular biology that cannot be explained by darwinistic evolution theory.)
Evidence Against Evolutionism From Molecular Biology
When the theory of evolution was first proposed by Charles Darwin (his Origin of Species was published in 1859), scientists knew very little about the makeup of the living cell. They assumed it to be a relatively simple blob of protoplasm. Therefore, it did not take much imagination to hypothesize that it might have sprung into existence by chance through random collisions of molecules.
However, scientific discoveries of the past few decades have built an incredibly strong case against the hypothesis that life is the result of random, unplanned processes.
In fact, evidence from many areas of science has made the theory of evolution a theory that rests, not primarily on empirical evidence (i.e., evidence acquired through experiment and observation), but on philosophical presuppositions (a faith based on preconceived ideas of what the world is like). The scientific evidence itself continues to increase in opposition to the theory.
One of the most exciting areas of evidence to be uncovered by scientists in recent years has been in the field of molecular biology.
A book written by Michael Denton entitled Evolution: A Theory in Crisis was published in 1986 by Adler and Adler. His book, and others like it written by other molecular biologists (e.g., Michael Behe), have been on the cutting edge of a movement that is presenting staggering evidence that is making the theory of evolution less and less tenable or defensible as time goes on.
This brief paper is an attempt to summarize a few of the discoveries from the field of molecular biology presented in Michael Denton's book that demonstrate the futility of the theory of evolution to explain the existence of life.
Denton's book is 358 pages of fascinating material from molecular biology and other scientific fields. It would be impossible to do it justice in a brief paper. My hope is simply that this paper will help others to be at least slightly familiar with the discoveries of molecular biologists, and that it will perhaps whet an appetite to read the entire book.
It would be helpful to put this paper in the context of my paper on The Second Law of Thermodynamics and Evolutionism for a better understanding of the laws of physics and mathematics that underscore the impossibility of these things happening as a result of random chance events.
Minimum Requirements for Self-Reproducing Cell
In the days when the theory of evolution was first proposed, it was assumed that there were certain molecules that had the characteristics necessary for reproducing themselves. The belief was that, over millions and millions of years, chance combinations of atoms finally reached a point where one of these molecules could suddenly reproduce itself. Thus began the simplest forms of "life." Gradually, more atoms were added, the molecules got more complex, multi-celled organisms developed, etc.
It is now known that there is no molecule that can reproduce itself without the involvement of many other critical molecules. Many have mistakenly believed that DNA molecules in isolation can somehow replicate themselves. They cannot. A biochemist named Harold Morowitz has tried to make an intelligent guess at how simple a cell could be, and still be able to reproduce itself. He has hypothesized that it might be conceivable for a cell to be able to reproduce itself with as few as one hundred protein molecules, all doing their respective functions (e.g. providing a cell membrane; synthesizing fats; providing energy; synthesizing the building blocks of DNA--the nucleotides; and synthesizing proteins). The cell would need a few messenger RNA molecules, ribosomes, enzymes, and, of course, a DNA molecule.
There is no way for scientists to conceive of a cell reproducing itself with less complexity. These are bare minimum requirements. In fact, no known cell reaches this degree of simplicity, but this hypothetical cell represents the bare minimum of "ingredients" that could conceivably be self-reproducing.
However, even this bare minimum cell, the simplest conceivable unit capable of self-replication, would be incredibly and awesomely complex. It would not be a "blob of simple protoplasm." It would be an exquisitely complicated living "machine." Each of the 100 or so protein molecules is an intricate combination of thousands of atoms. The DNA molecule is an intricate arrangement of literally billions of atoms.
Even in its simplicity, this cell would be made up of billions of atoms which would have to be arranged in an extremely complex organization. Michael Denton says it this way:
There is no continuum of functional forms through which the gradual evolution of the cell might have occurred--just a yawning gulf which can only be crossed in one vastly improbable leap. (p. 260)
He adds:
The complexity of the simplest known type of cell is so great that it is impossible to accept that such an object could have been thrown together suddenly by some kind of freakish, vastly improbable, event. Such an occurrence would be indistinguishable from a miracle. (p.264)
Scientists now know that proteins are extremely complicated three-dimensional chains of several thousand atoms. These atoms are arranged very precisely depending on the function of the protein. Each protein molecule is made up of a "backbone" of amino groups and carboxyl acid groups, linked by carbon atoms. All along the length of the molecule are amino acids, arranged as "side groups" in a very precise fashion, depending on the function of the protein.
As the study of protein molecules progressed, it became evident that proteins of similar function, but in different organisms, had slightly different sequences of amino acids.
Now the study has progressed to the point that it is possible to state with mathematical precision the degree of divergence (difference) in the amino acid sequences of similar proteins from one species to another. For example, a protein molecule that performs a certain function in the cell of a dog might be 17% different from a protein molecule that performs the same function in a fish.
Evolutionists expected that these differences would support their theory. They would have predicted that the protein molecules from the cell of yeast, for example, would perhaps be slightly different from the proteins that performed the same functions in a bacteria cell, but far more similar to the bacterial protein than the proteins from a vertebrate would be. The idea was that the yeast was closer to the bacteria on the "evolutionary ladder" than a vertebrate was, therefore their proteins should be more alike (less divergent). Evolution theory would have predicted that the differences between protein molecules would become gradually and progressively larger as organisms moved up the evolutionary ladder.
However, the evidence is now quite conclusive. The protein from yeast, to continue the above example, is as mathematically divergent from the bacteria protein as the protein from a human. And, in fact, so are the proteins from birds, fish, insects, and even plants!
Instead of a "chain" of divergences leading gradually up from simple species to complex ones, the proteins of each subclass are essentially "equidistant" in divergence from the proteins of the other subclasses. There are no "intermediates" connecting the subclasses.
This phenomenon has now been observed and cataloged for many proteins in many different species.
This evidence has been devastating for the theory that species have gradually changed from simple to complex. Had that theory been true, the divergences at a molecular level, where the changes must have taken place, would have grown gradually and sequentially larger and larger as the species moved up the evolutionary ladder. There should be no "breaks" in the degree of divergence, only a smooth continuum. Instead the differences are consistent and have startling mathematical precision.
Interdependent Molecular Functions
Another discovery that has been devastating for proponents of Darwinism is the amazing degree of interdependency that is found in the functions of the molecules of life.
For example, the mechanism of protein synthesis is dependent upon a cell membrane. But the cell membrane is dependent upon the existence of a protein synthesis mechanism!
Similarly, the protein synthesis mechanism requires energy. But the provision of that energy depends upon specific proteins that have already been synthesized.
In the same vein, the information for the assembly of protein components is stored in the DNA. But in order to obtain this information, proteins must exist that have been generated by the protein synthesis mechanism.
Cells have an accurate translational system (systems that allow the information contained in a DNA molecule to be transferred to other molecules) that totally depends on efficient enzymes. But these enzymes cannot be produced without an accurate translational system.
Examples could go on. The point is that it is impossible to conceive of a situation which gradually led to the conditions which enable a cell to self-replicate. The functions had to exist all at once, because each is dependent on the other.
The Fallacy of Homologous Structures
One of the stronger arguments for macro evolution has been the argument of homologous structures. Evolutionists use the word "homologous" to refer to biological structures in different creatures that seem to correspond to each other. The logic is, for example, that the arm of a man, the leg of a dog, the leg of a horse, the wing of a bat, the paddle of a porpoise are all built on similar basic plans. Therefore, it seems reasonable to assume that one evolved into the other. They are, the argument goes, powerfully suggestive of a common ancestor.
However, now it is possible to trace these structures to the genetic systems that lie behind them. And the fact is now known that structures that, on the surface, seem to be homologous are based on totally non-homologous genetic systems. In other words, the homologous structures are arrived at by completely different genetic paths. Had it been found that the same gene was responsible for similar structures in different species, it might have strengthened the argument for evolutionism.
One example of this is the case of the alimentary canal (the passage in the body that food goes through). It seems obviously homologous from one vertebrate to another. But it has been found to form along completely divergent paths in different species. It forms "from the roof of the embryonic gut cavity in sharks, from the floor in the lamprey, from the roof and floor in frogs, and from the lower layer of the embryonic disc, the blastoderm, in birds and reptiles." (Page 146)
There are many other examples of the same phenomenon. The bottom line is that homology in different species cannot be traced back to similar genetic events in those same species.
Also in the area of homology, it has proven to be very difficult for Darwinists to propose a reasonable explanation for why both the hind legs and the fore legs of vertebrates should be so strikingly similar (homologous) when they supposedly evolved along entirely different evolutionary paths (i.e., no one claims that forelimbs evolved from hindlimbs!). The arms or forelegs are said to have evolved from the pectoral fins of a fish, and the legs (hindlegs) from the pelvic fins. How could millions of years of random accumulations of tiny changes lead to such strikingly similar patterns in spite of the fact that the limbs are by no means identical?
Of course, creationists would argue that similar structures in various species simply point to the fact that these structures have a common Designer who designed the structures for similar purposes. The fact that He often chose different genetic paths to similar structures could be taken as an indication that He did not intend to leave evidence that might lead us to assume erroneously that these things simply "evolved" on their own.
Steve Hall
February, 2000
steve@aboundingjoy.com
© 2000 Steve Hall. Permission is hereby granted to quote from these web pages, in part or in full, as long as the following statement is included: "© 2000 Steve Hall (steve@aboundingjoy.com). Quoted by Permission."
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