Re: Oog
Geplaatst: 27 dec 2014 15:30
He makes three criticisms, all taken from the Discovery Institute playbook:
1. Life is too complex to have originated naturally. Here we see the usual arguments: life requires both proteins and DNA, and neither could have originated without the other. The co-evolutionary scenario, and involvement of RNA in this, isn’t mentioned. And he makes the usual bogus statistical arguments for why a “specified” DNA was unlikely:
Even if there was a self-organizing pattern, the probability of even a short strand of nucleotides occurring in a precisely specifi ed linear pattern that would code for even the smallest single-celled organism with approximately 250 genes has been calculated to be 1 in10150—1 in 1070 less than the chance of finding a particular electron in the entire universe (25).
Reference 25 is to a paper by Bill Dembski. Indeed, throughout his paper Kuhn quotes DI “experts” like Dembski, Jon Wells, and David Berlinski. His conclusion about the origin of life is absurdly funny:
Based on an awareness of the inexplicable coded information in DNA, the inconceivable self-formation of DNA, and the inability to account for the billions of specifically organized nucleotides in every single cell, it is reasonable to conclude that there are severe weaknesses in the theory of gradual improvement through natural selection (Darwinism) to explain the chemical origin of life. Furthermore, Darwinian evolution and natural selection could not have been causes of the origin of life, because they require replication to operate, and there was no replication prior to the origin of life.
He doesn’t seem to realize that one could consider replication as an essential property of life, and that the ability of replicate would have been strongly selected for among early proto-life forms. The last sentence above is simply gibberish.
2. Cellular systems are irreducibly complex, and could not have evolved. Kuhn tries to dazzle the reader with examples of complexity, but shows no awareness of what “irreducible complexity” really is: complexity whose intermediate steps could not have been adaptive during evolution. And, of course, though he quotes Behe and Wells at length, he doesn’t give any examples. It’s simply the argument from ignorance.
Although Nilsson and Pelger, for example, showed in a cool computer model that a complex camera eye could easily evolve, and in relatively few generations, from a simple light-sensitive pigmented eyespot, Kuhn dismisses that because one also requires the evolution of a complex brain apparatus and light-sensitive pigments to interpret the images. Ergo Jesus:
Thus, each of these enzymes and proteins must exist for the system to work properly. Many other mathematical and logistical weaknesses to the Nilsson example of eye evolution have been uncovered (28). In summary, the eye is incredibly complex. Since it is unreasonable to expect self-formation of the enzymes in perfect proportion simultaneously, eye function represents a system that could not have arisen by gradual mutations.
Reference 28 is to a DI commentary by David Berlinski.
3. We don’t have any transitional fossils. This claim is even more extreme than those made by the Discovery Institute. Kuhn dismisses (or rather, ignores) the transitional fossils between early hominins and modern humans, and simply asserts that the genetic differences between modern apes and modern humans preclude the existence of a common ancestor:
The ape to human species change would require an incredibly rapid rate of mutation leading to formation of new DNA, thousands of new proteins, and untold cellular, neural, digestive, and immune-related changes in DNA, which would code for the thousands of new functioning proteins.This rate of mutation has never been observed in any viral, bacterial, or other organism. The estimation for DNA random mutations that would lead to intelligence in humans is beyond calculation. Therefore, the recently discovered molecular differences between apes and humans make the prospect of simple random mutation leading to a new species of Homo sapiens largely improbable (35).
Lots of those human-ape differences involve transposons or neutral changes in “junk DNA,” whose accumulation is unproblematic. Before one can assert that human evolution is impossible, one has to have some idea of the number of relevant genetic changes separating us from our relatives (changes important in our physiological, cognitive, and phenotypic differences), and then show that such changes could not have occurred given estimates of mutation rates and time. Kuhn does not do this, but merely asserts that it couldn’t have happened. He has no idea how many selected changes separate us from our relatives.
As for other transitions, he dismisses the “fishapod” Tiktaalik roseae as “based on a recovered bone fragment representing the wrist structure that would be necessary for moving on land,” quoting—get this—Casey Luskin as an authority. If you know anything, you know that Tiktaalkik was represented by far more than a wrist bone: there was a head, for example, and a shoulder girdle, all of which looked transitional between fish and amphibians. And though Kuhn makes statements like this:
However, the modern evolution data do not convincingly support a transition from a fish to an amphibian, which would require a massive amount of new enzymes, protein systems, organ systems, chromosomes, and formation of new strands of specifically coding DNA. Even with thousands of billions of generations, experience shows that new complex biological features that require multiple mutations to confer a benefit do not arise by natural selection and random mutation. New genes are difficult to evolve. The bacteria do not form into other species. A reliance on gross morphologic appearances, as with fossils, drawings, and bone reconstructions, is severely inadequate compared to an understanding of the complexity of the DNA and coding that would have been required to mutate from a fish to an amphibian or from a primitive primate to a human.,
he fails to realize that this is all moot because we know it happened: we have the fossils! We have transitional forms between fish and amphibians, amphibians and reptiles, reptiles and mammals as well as between reptiles and birds, and of course all those fossils in the hominin lineages. Kuhn mentions none of these. The man, educated surgeon though he may be, is completely ignorant about evolution. He’s simply a mouthpiece for the Discovery Institute.
At the end, Kuhn claims that all these weaknesses of neo-Darwinism require a new paradigm to explain the origin and evolution of life:
Irreducibly complex systems involving thousands of interrelated specifically coded enzymes do exist in every organ of the human body. At an absolute minimum, the inconceivable self-formation of DNA and the inability to explain the incredible information contained in DNA represent fatal defects in the concept of mutation and natural selection to account for the origin of life and the origin of DNA. As new theories emerge that explain the origin of life, the inevitable emotional accusations of heresy and ignorance are not surprising in a period of scientific revolution. It is therefore time to sharpen the minds of students, biologists, and physicians for the possibility of a new paradigm.
Although he doesn’t specify what this new paradigm is, I suspect it involves an Intelligent Designer, aka Jesus.
This paper is rife with mistakes, misguided appropriations from the creationist literature, and simple ignorance of the evidence for evolution. It’s an embarrassment to the author, to the journal, and to the field of medicine as a whole. I call on the journal to retract this paper, for if it doesn’t, then the Proceedings of the Baylor University Medical Center will be forever tarred as a vehicle for creationist nonsense.
About the Author
Jerry Coyne
Jerry A. Coyne, Ph.D is a Professor in the Department of Ecology and Evolution at the University of Chicago and a member of both the Committee on Genetics and the Committee on Evolutionary Biology. Coyne received a B.S. in Biology from the College of William and Mary. He then earned a Ph.D. in evolutionary biology at Harvard University in 1998, working in the laboratory of Richard Lewontin. After a postdoctoral fellowship in Timothy Prout's laboratory at The University of California at Davis, he took his first academic position as assistant professor in the Department of Zoology at The University of Maryland. In 1996 he joined the faculty of The University of Chicago.
Coyne's work is focused on understanding the origin of species: the evolutionary process that produces discrete groups in nature. To do this, he uses a variety of genetic analyses to locate and identify the genes that produce reproductive barriers between distinct species of the fruit fly Drosophila: barriers like hybrid sterility, ecological differentiation, and mate discrimination. Through finding patterns in the location and action of such genes, he hopes to work out the evolutionary processes that originally produced genetic change, and to determine whether different pairs of species may show similar genetic patterns, implying similar routes to speciation.
Coyne has written over 110 refereed scientific papers and 80 other articles, book reviews, and columns, as well as a scholarly book about his field (Speciation, co-authored with H. Allen Orr). He is a frequent contributor to The New Republic, The Times Literary Supplement, and other popular periodicals.
