Header 1

Our future, our universe, and other weighty topics


Wednesday, September 27, 2023

The Negligible Presence of Evolutionary Explanations in Six Biochemistry Textbooks

One of the bad habits of Darwinist literature is to incessantly quote a misleading statement by the geneticist Theodosius Dobzhansky, one making it sound like evolutionary explanations are an indispensable part of biology. But to help show that Darwinism is actually a quite dispensable part of modern biology, let us look at how little presence evolutionary theory has in recent textbooks of biochemistry. You can verify my statements below by using the links to see the books on www.archive.org, where you can use that site's text search feature to look for phrases such as "evolution" and "natural selection." 

  • The 32nd edition of Harper's Illustrated Biochemistry is an 813-page 2023 textbook describing cells, genes, enzymes, proteins, metabolism, hormones, and biochemistry in the greatest detail, with abundant illustrations. The book makes no mention of Darwin and its only use of the term "natural selection" is to ask on page 718 a question whether aging evolved through natural selection. The book makes only a handful of uses of the term "evolution": a vacuous statement that new insights have been gained about human evolution; a statement that something has been "highly conserved" throughout the evolution of enzymes; a brief speculation that something "might allow more rapid evolution of biologic function";  a claim that "jumping genes...profoundly affect evolution"; a mention that PCR is used to study evolution; a claim that "the evolution of a diverse array of freely circulating blood cells was critical to the development of animal life" (a statement in which the word "evolution" was superfluous and could have been replaced by "origination" or "appearance"); a claim that gene duplication and exon shuffling "contributed to the molecular evolution of the coagulation system"; a claim that genetic variability "furthers evolution"; and a question asking something whether evolution should increase lifespan. This being the book's only references to evolution, evolution has a negligible presence in it. 
  • The sixth edition of Textbook of Biochemistry for Medical Students by D.M. Vasudevan and others is a 1995 672-page textbook that makes no mention of Darwin or natural selection, other than to say on page 500 that "Darwin's natural selection" deletes abnormal genes.  The book makes only a few references to evolution, which are these:  on page 29 it says amino acid sequences are conserved during evolution; on page 305 it uses "evolution" merely talking about change in carbon dioxide;  on page 472 it merely says "as the evolution proceeds, DNA content has also increased";  on page 486 it merely says that "in the pre-cellular epoch, nucleic acids were biological catalysts; and in course of evolution proteins took up this this activity"; on page 498 it says that "evolutionary relevant mutations tend to accumulate in 'hotspot genes'"; on page 503 it says "although rare, beneficial spontaneous mutations are the basis of evolution," providing no examples; and on page 617 it says DNA is used to study evolution. This being the book's only references to evolution, evolution has a negligible presence in it. 
  • The third edition of Marks ' Basic Medical Biochemistry:  A Clinical Approach by Michael Lieberman and Allan D. Marks is a 2009 textbook of more than 1000 pages. The book makes no mention of either Darwin or natural selection. The book makes only a few uses of the word evolution: on page 83 it carelessly says that "divergent evolution" can occur if a gene "can mutate into a protein with another function" (a gene can mutate into a different gene, but cannot mutate into a protein);  on page 100 it says with a little hesitation that similar functions "are believed to be the product of convergent evolution";  on page 244 it merely says "a process known as exon shuffling has probably occurred throughout evolution";  on page 659 it refers to the non-Darwinian "evolution of an artherosclerotic plaque"; and on page 957 it merely says,  "Members of a homologous family have somewhat different structures and are related only by their evolution from the same ancestral gene" (again speaking carelessly, since people don't claim species evolve from a single gene). This being the book's only references to evolution, evolution has a negligible presence in it. 
  • The seventh edition of Principles and Techniques of Biochemistry and Molecular Biology edited by Keith Wilson and John Walker is a 772-page 2010 Cambridge University Press textbook that we might expect to have many references to evolution, given the claimed strong association between molecular biology and evolutionary biology. But the book never refers to Darwin or natural selection. The book only refers to evolution a few times: on page 192 it says studies on genome variation and evolution can be "viable"; on page 233 it refers to artificial molecular evolution; on page 249 it says during evolution mutations may be inherited; on page 541 it merely parenthetically refers to "evolution time"; on page 698 it says something indicates some chemical had an "early evolution"; and on page 730 it merely refers to a drug's evolution. This being the book's only references to evolution, evolution has a negligible presence in it. 
  • The fifth edition of  Biochemistry by Mary K. Campbell and Shawn O Farrell is a  793-page 2006 textbook. A search for "evolution" in the text produces 23 matches, but if you discard mere references in questions or thought assignments or captions or the appearance of the word "evolution" in cited books or papers, we have only about a dozen references to evolution. None of these references says much of anything. They consist of these: a line that merely refers to "an interesting frame of reference from which to consider evolution"; another line saying many have said the hydrogen bond is essential to the evolution of life; another line referring to two applications that "give molecular  information about the evolution";  another line mentioning researchers who "speculate that RNA polymerase evolved eons ago"; another line mentioning researchers who think that understanding something is important to understanding evolution; another line saying "these two classes of enzymes appear to be unrelated and indicate a convergent evolution"; another line saying "the evolution of aerobic metabolism...was an important step in the history of life"; another line saying certain organelles "may have been independently living organisms very early in evolution"; a claim that something "allows more opportunity for evolution." The only reference to natural selection is a passing reference to "billions of years of natural selection." Since such references are nothing of any real substance, evolution has a negligible presence in the book. 
  • The eighth edition of the Textbook of Medical Biochemistry by M.N. Chatterjea and Rana Shinde is a 2012 894-page textbook. Ignoring two or three places in which the word "evolution" is used in a question or student study request, the book has only about 7  places mentioning evolution, which are these: a claim that one thing "seems to have evolved later" than another; a statement that "the conservation of 'junk DNA' over millions of years may imply an essential function"; a claim that so-called junk DNA "may be an important genetic basis for evolution"; a mention that PCR is used to study evolution; a mention that genome research has some value in studying evolution; a mention that the ozone layer has "been present through much of evolution"; and a claim that some test can be used to judge whether or not something "is a pattern in evolution." Since such references are nothing of any real substance, evolution has a negligible presence in the book. 
It is just as if zero effort was being made in these six biochemistry textbooks to use evolution or natural selection as substantive explanations for the wonders of biochemistry, and that the only times the authors used the word "evolution" or the phrase "natural selection" was in rare superfluous uses of the word "evolution" or "natural selection." Similarly, a historian will typically make no substantive use of the concepts of insanity, psychosis or mental illness in explaining historical events; but very rarely in a long history book you may find a use of the word "insanity" or "psychosis" or the term "mental illness."

Why is it that substantive attempts to appeal to evolution as an explanation are missing from the pages of these six very long biochemistry textbooks?  It is because today's world of biochemistry is a realm of the most gigantic levels of systemic organization, fine-tuned functionality and targeted molecular machinery in which the slight and feeble 19th-century notions of Darwinism can't even get to first base. 

Not a student of engineering or probability, Darwin had the very naive idea that very impressive biological innovations could occur by a step-by-step process of random variation in which each random variation produced a benefit. He had this idea because he had no understanding of how many well-organized parts must be added to make an improvement in survival ability or reproduction ability of an organism. He had no idea that cells are enormously organized units that require millions of well-arranged proteins, that human bodies require about 200 types of cells and more than 20,000 types of proteins, and that each of these types of proteins require hundreds or thousands of well-arranged amino acids, which have to be arranged as carefully as the letters in a well-written paragraph for the protein to be functional. 

We see below an example of one of the thousands of types of very complex protein complexes known to today's biochemists. The page describing the protein complex tells us that the visual is a very big oversimplification, and that the actual complex is very much more complicated than what is depicted in the visual. 

very complex protein complex

The pie graph below asks: how many parts must be added at the right places to make some improvement or useful innovation? The right half of the graph shows the answer we get from modern biochemistry. In very many cases (a significant fraction of the cases) hundreds or thousands of parts of the right type must be added at the right places to make a new biological innovation. Biological functions such as flying or walking or vision require (among many other things) multiple new types of protein molecules, each of which require hundreds of amino acid parts of just the right type arranged in just the right way. Overall such improvements require thousands of new parts of the right type, added in the right places. Biochemistry provides us with countless cases corresponding to the light blue, purple and green wedges in the pie chart below.  Trying to explain such cases though some "each little change produces a benefit" ideology is a fool's errand. 

Evolution shortfall


Humans now make fantastically complex machines consisting of many thousands of well-arranged parts of the right type, and humans have used some of these machines (such as electron microscopes) to discover that our bodies have fine-tuned functional complexity more complex and more well-organized than any machines humans can make. So now we understand that a situation like the one depicted in the graph above holds true not just in biology but in many other fields such as computers, software and electronics. Just as you can't explain the accidental origin of a computer or a smartphone or an automobile, you can't credibly explain the origin of biological improvements or biological innovation requiring hundreds or thousands of well-arranged parts of just the right type, using weak Darwinian ideas such as the idea of an accumulation of favorable random mutations. Perhaps sensing the futility of such attempts, many of the authors of biochemistry textbooks don't even try to present Darwinian explanations for the wonders of biological organization that they describe.  They limit themselves to rare quick mentions of evolution, and pay only the tiniest lip service to evolution.  

No comments:

Post a Comment