Science Article

July 1999

The Failure of Homolgy
By William Browing

"Homology" is a science which studies similarities between organisms, and is the basis for classification of living things.  When Evolutionists look at the similar structures of the arms or wings of mammals, they assume this means they had a common ancestor.  Creationists see the same data and believe it is evidence of a Common Designer.

            Since relationships are the basis for classification in biology, structural similarity is of extreme importance to Darwinism.  Darwin proposed an explanation for the many common features of the living world that was appealing to naturalists.  He theorized that the discontinuous groups of organisms descended from common ancestors.  Closely-related groups (e.g. reptiles, birds, and mammals) must have shared a relatively recent common ancestor. 

            Darwin's  theory  of "descent with modification" provided a naturalistic mechanism for the natural relationships between groups of organisms.  It explained why the groups into which animals were classified seemed to be part of a natural framework, rather than merely an invention of the classifiers.  Darwin believed the explanation, in terms of descent from a common ancestor was of primary importance to his theory.  He  said that the "argument from classification" was so decisive, that on that basis alone, he would adopt his theory, even if not supported by other arguments. ¹  In Origin of Species, he wrote:

"The Natural system is founded on descent with modification:  that the characters which naturalists consider as showing true affinity between any two or more species, are those which have been inherited from a common parent, and in so far, all true classification is genealogical; "

The phenomenon of homology has remained the mainstay of the argument for Evolution right down to the present day.

**Evidence against Ancestors:  Embryology**

            From Darwin's time until now, evolutionary biologists have believed that common descent implies some very important propositions about homology and embryonic development.  The theory predicts that, if species with similar forelimbs inherited them from a common ancestor, they ought to be traceable to embryonic development and common genes..  Modern science has not borne out this prediction.  In fact, homologous structures are arrived at by different routes. ²  Since homologous structures don't come from the same embryological structure, they therefore cannot have the same genetic origin. ³

            These problems that the sciences of genetics and embryology have raised are insurmountable, and have resulted in failure of evolutionary homology.  It is true that vertebrates all pass through an embryonic stage in which there is a resemblance, but the developmental processes leading to this stage are very different.

            In early stages of embryonic development, we find that the cells that give rise to the three main structures of the embryo (ectoderm, mesoderm, and endoderm) are extremely different;  so different, in fact, that were it not for the close resemblance of adult vertebrates, "it seems unlikely they would have been classified in the same phyla," according to Dr. Michael Denton.

            In his book, ⁴ Dr. Denton compares the  formation in the early development of what’s called the blastula (pre-embryo) for three vertebrates having the same basic design for the forelimbs.  Denton says,  “Homologous struc- tures cannot be traced back to homologous regions in early states of embryogenesis.”  The specific sites for many vertebrate forelimbs (e.g.. newt, lizard, and man) have been identified, and they not only differ in location, but the number of associated structures are different!

            In his book "Creation-Evolution Controversy",  Wysong states, ⁵

"The embryological development of every kind of plant and animal is unique, . . .  At any stage, the biochemical and genetic uniqueness (DNA sequence) of every organism can be differentiated from that of any other kind"

So, Darwinism fails to produce the required embryological relationships.  And what of genetic similarity?

**Similar structures from different genes**

            Modern biologists have assumed that corresponding embryonic parts are themselves controlled by homologous genes.  However, this evolutionary assumption must be rejected by the discovery that apparently homologous structures are specified by quite different genes in different species. ⁶  On this basis, Sir Gavin de Beer challenges the theory of common ancestors in his 1971 paper on homology:

"...what mechanism can it be that results in the production of homologous organs, the same patterns, in spite of their not being controlled by the same genes? ⁷

(Note:  most genes control more than one organ ('pleiotropy'). Evolutionists use this fact to argue for systemic change with the fewest number of mutations.  But the principal importance of pleiotropy is that, non-homologous genes specify homologous structures.) ⁸

            It’s as if there is a message encoded into the biological design, saying “No Evolution”.  It is paradoxical that the same homologous resemblance which serves to link all the members of one class together into a natural group also serves to distinguish that class unambiguously from all other classes.  Wouldn't random chance mutations have produced many designs for the same function? Why the Creator chose to reuse the same basic designs over and over, and then to arrive at them through different developmental paths and blueprints, could be God's way of imprinting the message:  "Evolution did  not occur."  (See Walter ReMine, Biotic Message)

**Molecular Homology fails, too.**

            Evolutionists  look for sequences in certain molecular structures that will give them an idea of the direction that evolution went.   They look at proteins and DNA molecules and speculate which ones have been derived from common ancestral molecules. ⁹

            The procedure for comparing amino acid sequences for similar proteins in different organisms is to count the number of positions in the sequence that are different, expressed as a percentage.  The results do not show evolutionary relationships.  Incredibly, in hemoglobin  differences, man is a closer relative of the lamprey eel (marine vertebrate) than are fish.  What a surprise for someone expecting the homology of another protein (Cytochrome C) to prove evolution.  The data show the exact opposite.  There is less difference between a bacterium and a horse than between a single celled bacterium and a single-celled yeast. ¹⁰

**Conclusion:  Common Structures mean Common Designer**

            In the last analysis, the facts of comparative anatomy provide no evidence for evolution in the way conceived by Darwin. ¹¹

The failure of homology to validate the predictions of Darwinism  is not as well known as "Darwin's enigma" (the fossil problem).  But it is even more important, since like molecular biology ¹², it shows that so-called "higher organisms" could not have evolved from common ancestors in any gradual, step-by-step process of random mutations and natural selection.  Rather, homology is powerful testimony to a Common Designer.

                   References:

1)  Johnson, Philip.  Darwin on Trial,  p. 65.

2)  Denton, Michael.  Evolution: Theory  in Crisis, 1986, p. 146.

3)  Bliss, Richard. Origins, Creation or Evolution,  1988.

4) Denton, 1986.

5)  Wysong, R.K., DVM. The Creation-Evolution Controversy,  1976.

6)  Denton, 1986, p. 149.

7)  de Beer, Sir Gavin.  "Homology, an Unsolved Problem," Oxford Biology Readers,  Oxford University Press, 1971.

8)  Denton, 1986.

9)  Bliss, 1988, p. 25.

10)  Sunderland, Luther.  Darwin's Enigma,  1987.

11)  Denton,  1986.

12)  Behe, Michael.  Darwin's Black Box,  1996.