How Scientific Myths Are Made
A myth, one might imagine, is a story or explanation that is widely believed, but has no basis in fact. While there were numerous myths in the past, modern man believes that he has no need for such fabrications. Science, after all, undertakes to explain everything, and it is empirical and objective, so the saying goes. But even in science, some myths do creep into the public consciousness. It is interesting to notice how popular misunderstandings of scientific information appear and are propagated. An example springs to mind. Consider the recent studies on the “age” of the human race, for example. The conclusions and some headlines were actually misleading. One wonders how many readers obtained an inaccurate understanding of the issue. Let us investigate that case.
Genetic information is stored in very long molecules called DNA. There are four different components which are connected like beads in different orders (sequences). The arrangement of these components (called base pairs) is what conveys information. This code determines the characteristics and talents of any given organism. We hear a lot about the human genome project, the programme to identify the exact order of the estimated three billion base pairs which determine what humans are like. This information is broken up into shorter segments called chromosomes.
Of course the genetic information in humans is different from that of a flower, or a bumble bee, or even of an ape. But how did each organism obtain its characteristic information code and its typical characteristics? One logical possibility is that each kind of organism was separately designed. Another is that the code changed with time, so that more and more differences accumulated. Indeed the code does change somewhat with time. The process for change in the information code is called mutation. A substitution made, in error, of one base pair for another, does occasionally occur. Evolutionists believe that this process continues indefinitely and leads to new information and new kinds of organisms. Creationists believe mutation leads only to variation within an already established group.
Beginning in the mid 1980s, based on comparison of DNA base pair sequences, molecular biologists began to look for clues about human origins. Allan Wilson and colleagues set out to find out how much variation among humans there was in one small part of the genetic code. He assumed that a lot of variety in the code would indicate that the present population was many generations removed from a possible single ancestor. Alternatively a small amount of variation would suggest a short time interval. To study the issue he decided to look at a piece of DNA that is passed directly from mother to offspring but never involves the father. This separate piece of genetic code comes only from the mother since an egg contributes not only a nucleus (containing the main body of genetic information) but also cell substance. The cell substance includes tiny bodies (mitochondria) which contain their own separate tiny ring of genetic code. The father contributes no cell material to the offspring, but only a nucleus. It is evident that any variation in genetic material from the mitochondria must develop only through changes (mutations) in what has been handed down from the mother.
Assuming that all people are descended from one original mother, Wilson and colleagues studied the amount of variation in mitochondrial DNA in the present human population. They then estimated how long it would take to develop the present amount of variation. Of course the time that has elapsed from one female ancestor (called Eve by the scientists), to us today depends upon the mutation rate as well as the number of people involved. It could involve a few people reproducing over many generations, or many people having children in only a few generations. The answer the scientists obtained would be only as good as the assumptions inserted into the equations. The scientists plugged an assumed conservative mutation rate into their calculations. This would push the value in the direction of a long time interval.
The time estimate that the computer provided, came as a shock to the scientists. Colleagues termed the answer “really controversial” (Science 26 May 1995 p. 1141). The time elapsed from a single ancestor “Eve” to the present, calculated in the range of 140,000 to 200,000 years, was astonishingly short. Scientists had expected a value closer to five million or more years. Later calculations revised the interval down as far as 100,000 years. But there was more bad news. We hear a lot about how our genetic code is so similar to that of the chimpanzee (our supposed closest relative). But investigations of mitochondrial DNA suggested that the difference between humans and chimpanzees might be a whopping 69%! (Science 27 September 1991 p. 1506) None of this looked good for evolutionary interpretations. As a result, scientists looked forward to studies on males that might revise the female results upward toward longer ages. Unfortunately for the evolutionists, the results, when they came, revised the numbers towards younger, not older. But the headlines didn’t give this impression.
Males do have some genetic information that females lack. Part of the Y (sex determining) chromosome is unmatched by anything on the X chromosome (which both males and females possess). Molecular biologists therefore chose to study such a piece of Y chromosome in 38 men from around the world. It was fully expected that there would be plenty of variation among the various races. But scientists found no variation at all. The DNA was exactly the same. As a result of this unexpected finding, the scientists had to revert to plan B – damage control. They set out to integrate this “mathematically rather awkward situation” (Science 26 May 1995 p. 1142) into an evolutionary scenario. How long, they asked their computers, could this piece of DNA stay unchanged in an otherwise evolving human population.
Two answers were obtained. If there was, in each generation lasting about 40 years, approximately one father worldwide who had children, so that over all the generations a total of only 7500 men were involved, then the DNA could stay unchanged for as long as 270,000 years. A further necessary condition was that this “super father” had to be fathering children all over the world…. quite the busy schedule! Alternatively, if more men per generation were involved, the computer suggested a maximum age for mankind of 27,000 years. This latter value approached creationist expectations. Even for the smaller value, the calculated number indicated the maximum possible time interval, not actual age. The time could, in reality, be much shorter.
Although the assumptions needed to obtain the 270,000 year estimate were totally impossible, the authors chose this value and claimed that it coincided with female mitochondrial DNA (“Eve”) calculations. Actually the female dates had been revised downward and the high date for the males was totally preposterous. Nevertheless the May 26, 1995 Globe and Mai headline read “Male ancestor of humans lived about 270,000 years ago” while the Edmonton Journal on the same day, proclaimed “Our ancestors traced to 270,000 years ago”. The myth of the relatively remote male ancestor had been born. This myth continues to flourish. An article in the Edmonton Journal (December 21, 1995) reprinted from the Knight-Ridder newspaper chain, refers to the 270,000 year old male ancestor. So does an article in Earth (February 1996 p. 34). Lest we confuse the scientific “Adam” and “Eve” ancestors with Biblical figures, both these publications caution that the scientific “Adam” and “Eve” did not live at the same time and both had lots of other human contemporaries who left no offspring. Indeed?? What happened to the offspring of these other people? Good question.
Richard Dawkins is quoted as remarking “Mitochondrial Eve is the most recent woman of whom it can be said that all modern humans are descended from her in the female-only pathway.” (Edmonton Journal, December 1995 ) Similarly Francisco Ayala is said to have remarked “This ZFY Adam is the individual from which all humans have inherited the ZFY gene, but he is not our only ancestor in his generation. …. We have inherited the other thousands of genes from many other contemporaries of this Adam.” (Edmonton Journal) If this were so, how exactly, might this work?
Perhaps we can concoct an illustration. Imagine that there once was a delightful town called Blythville. The townsfolk were happy, red-headed people, short in stature and freckled of face. One day there came to town a tall dark stranger called Pedro. His eye fell on Betty and they were married. They produced several sons, all like their dad. The local girls all said that if they could not marry a tall dark son of Pedro, then they would not marry anybody. Pedro’s sons married various local lassies, but none of the local lads managed to produce any children at all. From then on all the young in the village were descendants of Pedro on the male side, but of several local ladies on the female side.
Some years later Blythville was visited by a young lady, a blonde bombshell named Agatha. The young men were entirely smitten. She married a handsome young man named Juan Pedro. The resulting daughters looked like Agatha while the sons looked like the remote ancestor, Pedro. After that only daughters of Agatha had any success in marrying the local dudes. The redheaded people of the village had been entirely replaced, and their contribution to the gene pool was almost negligible. It was as if they had never been.
This sort of scenario, but on a worldwide scale, is what some population geneticists suggest happened to the human race. Of course this is a drastically simplified portrayal of the situation. All Pedro’s male offspring need not, and probably would not look like him. Similarly Agatha’s daughters and grand daughters need not all resemble her. We do need however, a reason why the other suitors would be excluded from reproducing. Either the others were unable to find mates, or their offspring did not survive. Did Pedro and Agatha kill off all children of non-relatives or did they outcompete everybody else for scarce resources? It gets quite ridiculous when all non-family children are eliminated on a worldwide basis, not just in one centre.
If a myth is an improbable tale, this “scientific” explanation of human origins appears to qualify as one. Some people would claim, on the other hand, that the Biblical Adam and Eve are themselves the substance of myth. This is not a recent suggestion. Christians would do well however to consider New Testament references to Adam. The apostle Paul’s direct connection of the work of Christ as an antidote to the fall of Adam provides impressive corroboration of the Genesis account. Christ himself refers to the historicity of Adam’s son Abel (Matt 23:35). Individuals who insist on a non-religious explanation for mankind, can scarcely be critical of the current scientific myth since they have little to replace it. Christians on the other hand, have the right and privilege to be critical. After all, we know the truth.
The first man Adam was made a living soul; the last Adam was made a quickening spirit. (I Cor. 15: 45)
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