Wednesday, November 23, 2016



In a recent book [Axe, Douglas.  2016.  UndeniableHow Biology Confirms Our Intuition That Life Is Designed.  Harper One, HarperCollins, NY, NY. 298 pp.], Axe uses the flawed logic of the “Intelligent Design – Special Creation” community in an impressive attempt to support childhood intuition of cause and purpose as an indication of the truth of the special creation of each species.

Once special creation is assumed for species creation, on the basis of childhood intuition, he postulates that all things have a cause and are made according to plans that the creator uses to produce each species.  He “proves” this by showing the statistical impossibility of DNA sequences specifying one characteristic ever being produced by a chance result by his view of natural selection.  Unfortunately for him, natural selection does not operate in the direction he assumes.  It is not really selection of the new variety, it may just be the failure of the old variety surviving or not expanding into new territory to which the new one may be better adapted.

For a concrete example consider human pigmentation.  Presumably, as we evolved in Africa we survived there better by having high levels of melanin pigmentation in our skin.  That provided several possible benefits including protection from overproduction of vitamin D in the skin and damage from high levels of U-V light in the tropics; those living in tropical forests had coloration making it difficult for predators to find them, whereas in savanna and desert the dark color absorbed more heat sooner in the morning to improve their morning activity start.  Conversely, those migrating to colder climates benefited by, partial loss of pigmentation that allowed enough vitamin D to be produced, and less visibility to predators where snowy conditions occurred.

More than one gene is involved in melanin production and each requires several biochemical steps.  The loss of any portion of the proper sequence of biochemical events can result in reduced melanin production, and if all genes have interruption of the process, the person will lack melanin pigmentation.  A similar process operates in most species, so changes (mutations) in the hereditary material have many ways to produce albinos.

The speed of such a selective process operating is shown by the fact that cave dwelling isopods in the central United States are most like the surface dwelling isopods nearby but lack melanin and eyes, among other cave-dwelling adaptations.  Mutation rates are such that studies seem to show that deleterious mutations seem to occur at least ten times more frequently than beneficial ones (with exception of where the loss is beneficial as noted for albinism).

So, mutations needed for evolution are random events producing inheritable variations in the DNA of a species.  The change does not get selected at the gene level, the selection is at the organismal level as a result of the survival value in the organism’s environment.  At the gene level, it is possible that loss of a feature may be just as important in evolutionary result as the gain of a new feature.  The potential for graded responses due to interactions within the body may complicate the process but evolution is neither a conscious process nor a struggle toward a particular goal.  That does not preclude the process from being directed by the Creator from before the creation of the universe.  That cannot be determined by the tools of science, nor by our philosophical or theological musings.


A slightly older book than Axe’s book is one by Elizabeth A. Johnson [Johnson, Elizabeth A.  2014.  Ask the Beasts: Darwin and the God of Love. Bloomsbury, London (2015 paperback) 323 pp. + XVIII.].  The book has outstanding coverage of evolution/God/science/theology/ecology.  The eighth paragraph (page 240) of chapter 9, Enter the Humans, has great coverage of human advances.  On pages 5 and 6 environmentalists will appreciate her statement of the horrible state of the earth.  And her pages 7 and 8 contain a concise presentation of the fallacy of the creation (intelligent design) versus science (evolution) debate.  I have not completed reading the book, but my sampling makes me give it an endorsement of outstanding.

Joseph G. Engemann    Kalamazoo, Michigan      November 23, 2016


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