Saturday, February 25, 2017

Book Review: The Edge of Evolution

Credentials
Michael J. Behe, Professor of Biological Science at Lehigh University, received his PhD in Biochemistry from the University of Pennsylvania, did post-doctoral work on DNA structure at the National Institutes of Health, and has authored more than 40 technical papers. In 1996, Behe authored his first book, Darwin’s Black Box: The Biochemical Challenge to Evolution, quickly becoming a founding father of the intelligent design movement and a lightning rod for vociferous criticism. His second book, The Edge of Evolution, was published in 2007 (a full-time job and nine children make it a challenge to write books).

The Upper Limit of Darwinism
As the title indicates, the main premise of the book is to determine the “edge” or upper limit of evolution by undirected, naturalistic processes, utilizing random mutations. Writing in a style that is easy for laymen to follow, yet engaging enough for those with some scientific background, Dr. Behe takes the reader to the molecular level where random mutations occur. By conceptualizing proteins as the “nanobots” of living organisms, the book details some of the complexity of these systems. Noting that nearly every major process in a cell is carried out by assemblies of ten or more protein molecules is only the beginning of the complexity: These nanobots must self-assemble. Then, for proteins to work jointly in the cell, binding sites must fit together similarly to a lock and key. The book points out that, to make Darwinian evolution work at this level, it would be necessary for five or six amino acids to change in a coherent manner to reach the higher order advancement of a new binding site. This may not sound like much, but the statistical likelihood as shown by the research of the development of only two new protein binding sites – to acquire some new, useful property in the cell – is the upper limit of Darwinism. Five or six beneficial changes are well beyond the limit. Behe shows that experimental research studies and hard statistical data are definitely not on the side of evolution by random mutation.

Evolution in microorganisms?
Behe examines in some detail effects of random mutations of three organisms that are ideal for this type of analysis:  Plasmodium falciparum (malaria), Escherichia coli, and HIV. Each has been studied extensively for decades and, during that time, genetic studies contain data for many thousands of generations, and multiple trillions of organisms. Additionally, these three organisms are ideal for study since the entire genome of each has been sequenced. For more than a century, E. coli has been studied in the lab and in one particular experiment; over thirty thousand generations - roughly the equivalent of a million years of human history – have been systematically studied. Certainly if random mutation and natural selection were the mechanisms of Darwinian evolution, we should see these little buggers evolving into some higher organism, right? If malarial cells have not evolved into a chimpanzee by now, then perhaps a sea snail? Not even close. In all these generations, there have been “No new protein-protein interactions, no new molecular machines”[1] and nothing even hinting at a new, higher level organism.

Perspective
To put these studies of bacteria and viruses into perspective, The Edge of Evolution gives an estimate of the total number of malarial cells worldwide in only one year as 10²ยบ cells. Compared with a rough estimate of the total number of “Primates in the line leading to modern humans in the past ten million years”[2] of 10¹². So, if Darwinism is the mechanism for primate evolution, then why has there been no sign of evolution in malarial cells, which outnumber (in one year alone) the total number of primates who have lived in millions of years by a factor of one hundred million? If orangutans, gorillas, and chimps evolved from lower primates, and humans evolved from there, we certainly should see significant evolution through random mutation from malarial cells. And, not only malaria, but also E. coli and HIV, which mutates at a dizzying rate. But, that’s not the case. Increased complexity is simply not happening and Behe has the hard scientific data to prove it.

Trench warfare or arms race?
One of the alleged examples of Darwinian evolution shown to students in the classroom includes sickle hemoglobin (usually a deleterious mutation) conferring malarial resistance. Other examples include mutations in protein binding sites that lead to antibiotic resistance. However, Behe explains that these examples are not progressive. They are more like acts of desperation, like burning one’s own bridges to stop the enemies’ advance during a time of war. This picture is contrasted with a very different type of warfare, the USA-Soviet arms race of the 1980s, in which deliberate, intelligent advances in technology were made. As the book points out, beneficial mutations at two sites in a protein is extremely rare and is near the upper limit of Darwinism. Furthermore, this example of malarial mutation, while beneficial, does not evolve any new, advanced, or complex machinery. This and other similar examples are demonstrations of what Behe terms “trench warfare”, not increases in complexity. 
                                                                           
Conclusion
Michael Behe employs a number of analogies that assist the reader in understanding the import of the molecular inner workings. Some of the alleged examples of evolution in progress are identified as debris in the gutter at one’s house, trench warfare, and a drunk climbing a small hill but failing to ascend the mountain. These analogies can be useful in applying the microscopic world to the macroscopic. “If there is not a smooth, gradually rising, easily found evolutionary pathway leading to a biological system within a reasonable time, Darwinian processes won’t work”.[3] Behe does admit common descent and he notes that Darwinian evolution does account for variation within species. The Edge of Evolution makes a very convincing case that the upper limit of natural selection via random mutation does not extend much higher than that. Well beyond the edge exists a high degree of fine tuning necessary for life, including:  multi-protein complexes, molecular machines, biochemical properties of DNA, phyla, classes, kingdoms, cells, origin of life, and so on. The conclusion is that “The major architectural features of life – molecular machinery, cells, genetic circuitry, and probably more – are purposely designed.”[4] But, atheistic Darwinists need not worry:  Behe draws no heavy-handed theistic conclusions from this and he is not a young earth creationist. He simply lays out evidence for the limits of Darwinism.



[1] Page 142
[2] Page 143
[3] Page 7
[4] Page 202

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