CLEARING THE PATH

Homology, embryology and vestigial organs are three more lines of evidence evolutionists have traditionally used, and continue to use, as evidence to back up their theory.  However, as you will see here, they have all been discredited.  An honest evolutionist cannot deny this evidence. 

Since 1859 the phenomenon of homology has been traditionally cited by evolutionary biologists as providing one of the most powerful lines of evidence for the concept of organic evolution. Darwin explained homology this way in the 6th edition of The Origins of Species: 

We have seen that the members of the same class, independently of their habit of life, resemble each other in the general plan of their organization. This resemblance is often expressed by the term “unity of type”; or by saying that the several parts and organs in the different species of the class are homologous….

What can be more curious than that the hand of a man, formed for grasping, that of a mole for digging, the leg of the horse, the paddle of the porpoise, and the wing of the bat should all be constructed on the same pattern, and should include similar bones, in the same relative position? (1)

The classic examples of homologous structures used by evolutionists are the forelimbs of vertebrates (animals with backbones).  Although a bat has wings for flying, a porpoise has flippers for swimming, a horse has legs for running, and a human has hands for grasping, the bone patterns in their forelimbs are similar.  Darwin argued that homology provided positive evidence that organisms had undergone descent from a common ancestor. 

The link between homology and common descent was so central to Darwin’s theory that his followers actually redefined homology to mean features inherited from a common ancestor. When neo-Darwinism arose in the 1930-40s homologous features became attributed to similar genes inherited from a common ancestor.  The phenomenon of homology has remained the mainstay of the argument for evolution right down to the present day.

The validity of the evolutionary interpretation of homology would have been greatly strengthened if embryological and genetic research could have shown that homologous structures were specified by homologous genes and followed homologous patterns of embryological development.  However, this is simply not the case. 

The fact is, the concept of homology can seldom be extended back into embryology.(2)

An honest reading of the literature makes it clear that Darwin’s usage of the term ‘homology,’ which he defines as that “relationship between parts which results from their development from corresponding embryonic parts” is just what homology is not.  The theory that homologous structures are products of similar developmental pathways does not fit the evidence, and biologists have known this for over a century.(4,5)

The evolutionary interpretation of homology is weakened even further by the fact that there are many cases of ‘homologous like’ resemblance which cannot by any stretch of the imagination be explained by descent from a common ancestor.  The similar pentadactyl design of vertebrate forelimbs and hindlimbs provides the classic example. 

The forelimbs of all terrestrial vertebrates are constructed according to the same pentadactyl design.  The humerus bone in the upper forelimb is analogous to the femur in the hindlimb. The radius and ulna in the lower forelimb is analogous to the tibia and fibula of the lower hindlimb. This pattern is attributed by evolutionary biologists as showing that all have been derived from a common ancestral source. 

Yet no evolutionist claims that the hindlimb evolved from the forelimb, or that hindlimbs and forelimbs evolved from a common source.  In the minds of evolutionists the forelimbs and hindlimbs must have arisen independently.  Yet it is difficult to explain the independent origin of structures which are incredibly similar in evolutionary terms.  Evolution requires a random accumulation of tiny advantageous mutations. 

Further, it is unreasonable to think that structures that are so similar in the forelimbs and hindlimbs could have resulted by purely random processes in all terrestrial vertebrates.  It’s extremely unlikely that there could be any natural selection process that necessitates there being five digits in both hand and foot or that only the thumb and big toe both be made up of only two phalanges, or that the forearm and lower leg be both made of two long bones, or that there be only one bone in the upper arm and leg. 

We seem forced to propose that during the course of evolution the gradual accumulation of tiny independent and random changes in two independent structures hit on an identical yet apparently arbitrary ground plan for the design of the forelimbs and hindlimbs.  It is beyond wishful thinking.

The current explanation evolutionists give to deal with this problem is to define homology in terms of common ancestry and then seek evidence for descent with modification that is independent of homology.  One line of evidence they try to use is from DNA sequencing.  However, molecular homology generates at least as many conflicting results as the more traditional approach. Another line of evidence they try to use is that of the fossil record.  What they have found, however, is that comparing fossils is no more straightforward, and probably less so, than comparing live specimens. 

It has become apparent that homology is not the clear indicator of ‘unity of type,’ that Darwin thought he explained by descent from a common ancestor.  Homology can never be explained from an evolutionary standpoint. 

The failure of homology to substantiate evolutionary claims has not been as widely publicized as have the problems of the fossil record.  Comparative embryology is much less glamorous than the biology of dinosaurs.  Nonetheless, it fits into the general theme that advances in knowledge are not making it easier to fit the patterns of nature into a Darwinian framework.  In the final analysis the facts of comparative anatomy provide no evidence for evolution in the way conceived by Darwin. 

Darwin knew that the fossil record was a serious problem for his theory.  He also knew that without a mechanism to explain how homologies were produced, his identification of archetypes with common ancestors remained open to challenge.  Thus it seemed to him the evidence from embryology was his best evidence in support of his theory.  He believed that similarities in early embryos demonstrated descent from a common ancestor and also revealed what that ancestor looked like. 

The development of an organism from fertilized egg to adulthood is called its ontogeny. Embryology studies embryos and their ontogeny.  In 1866, Ernst Haeckel published the biogenetic law which claimed that an organism’s embryological development (its ontogeny) repeats (or recapitulates) the stages of the adult form of its ancestors.  According to Haeckel, during its development, the embryo takes on successively the appearance of its evolutionary ancestors in the proper evolutionary sequence.  This view was also known as embryonic recapitulation.

Haeckel’s conclusions were actually deduced from evolutionary theory rather than inferred from any actual evidence.  Darwin was not an embryologist so he relied heavily on the works of others, including Haeckel.  Haeckel produced a series of drawings which supposedly demonstrated that the early stages of the development of various classes of vertebrates were virtually identical, and become noticeably different as they develop.  It was this pattern of early similarity and later differences as they developed that Darwin found convincing as evidence of descent from common ancestors.  The theory was widely heralded as proof of evolution.

Unfortunately for Darwin, it was found that Haeckel faked his drawings!  The entire theory was debunked in the 1920s, and yet for another fifty years was still found in high school and college text books.  History has clearly shown that theories that fit evolutionary preconceptions are usually not removed when they are discredited…at least not until there is an acceptable replacement.  That acceptable replacement did not happen until 1977, when Stephen Jay Gould published Ontogeny and Phylogeny,(6) which sought to clear up the matter once and for all. 

Five years earlier, Gould and Eldredge had produced their new vision of evolution, punctuated equilibria (click here for that page). After honestly assessing the fossil evidence and realizing it provided no evidence for evolution, they provided this theory as a way to help explain the data. Instead of slow change caused by beneficial mutations, supposedly evolution occurred in large jumps, explaining why no transition fossils have been found.  They completely de-emphasized Darwin’s lineage, in favor of indecipherable “bushiness.” Haeckel’s recapitulation theory was now a hindrance and could be conveniently disposed of. 

However, the theory of punctuated equilibrium is a vain attempt to explain away the lack of fossil evidence for evolution.  It does not remove the need for transitional fossils, but only states why those fossils were never found.  It claims to be scientific but then explains why evidence for it can never be found !!  There is also no mechanism to explain how it might work.  Punctuated equilibria is not a prediction of genetics or any other well-understood biological processes.  Rather, it is specially constructed to adapt evolutionary theory to explain the observed fossil record.  That’s not how science is supposed to work.

Vestigial organs are defined as biological structures that were formerly useful but now have no function.  Darwin argued that vestigial organs are the useless remnants of organs that previously had a function, thereby indicating an ancestral history.  

Evolutionists at one time listed about 180 organs in the human body considered to be useless vestiges of organs that were useful in man’s animal ancestors.  However, most classic cases of vestigial organs were later found to have a legitimate function that was previously unrecognized.  Some once had a function, but lost it through mutation and inbreeding.  Some are remnants of the reproductive structures of the opposite sex.  Others have a function, but are odd designs nonetheless.  

With increasing knowledge, this list has steadily shrunk until the number of so called vestigial organs has been reduced practically to zero.  Yet, evolutionists today continue to use the argument of vestigial organs as evidence for evolution.  However, anyone honestly looking at the evidence knows better.  Evolutionist S.R. Scadding points out that practically every supposed vestigial organ has been shown to have a useful function.  Further, he emphasizes that it is impossible to demonstrate conclusively that an organ has no function.  He concludes that “vestigial organs” provide no evidence for the theory of evolution.." (7)

The progressive failure of the argument from vestigial organs led some evolutionists to redefine it in terms of genetic throwbacks.  Since they never had a coherent method for distinguishing genetic throwbacks from ordinary malformations, they selected as “throwbacks” those malformations that happened to look ancestral.  However, whether calling them vestigial organs or genetic throwbacks, none of the structures evolutionists continue to site offer evidence to support evolution.

So as we can see, three more lines of supposed proof of evolution are nothing of the sort. We will next move on to the molecular evidence and what it shows.