On checking my files, I find the following archived postings: Article 3749 of talk.origins

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On checking my files, I find the following archived postings: Article 3749 of talk.origins: From: lew@ihlpa.ATT.COM (Lew Mammel, Jr.) Subject: Re: Denton's book Summary: I read it Message-ID: <8948@ihlpa.ATT.COM> Date: 15 Aug 88 22:42:03 GMT Organization: AT&T Bell Laboratories - Naperville, Illinois The main weakness I recall was a confusion between actual lines of descent and the modern representatives of the stages along these lines. This was most obvious in his discussion of cytochrome-c analysis. He declared that evolution predicted that ( say ) fish, frogs, and birds should have successively less correlation with a common ancestor in their amino acid sequences. This is not found, of course, since all these modern animals have been diverging for the same length of time from any common ancestor. Evolution predicts a hierarchy of groups, each of which is defined by a constant correlation with that group's common ancestor, and with the smaller more recently evolved subgroups having a higher correlation with their more recent common ancestor. The data fits this expectation very well, and this fit is rightly regarded as a brilliant confirmation of the phylogenies based on morphology. So if an author gets something THIS fundamental THAT wrong, where does that leave him? Out in left field, I say. Nevertheless, the book is coherent enough to make for some stimulating reading. That is, it may be challenging to discover the errors of argument in each case, but be aware of the author's predilection for unsound argument. I actually saw Denton's cytochrome-c argument repeated by a creationist ( Richard Bliss ) before I saw Denton's book. I reported this on the net several years ago. Another interesting, but spurious, argument is based on homologies of structures in the same organism. Denton states that hands obviously can not be evolved from feet, or vice versa, so that their similarities cannot be explained by descent with modification. Of course, a little consideration of the importance of segmentation in the development of individual organisms reveals the bankruptcy of this argument. ------------ Article 19567 of talk.origins: From: WHAMILTO@cmsa.gmr.com (Bill Hamilton) Subject: Comments on Evolution: A Theory in Crisis (Denton) Message-ID: <67819@rphroy.ph.gmr.com> Date: 1 Nov 91 19:49:01 GMT Organization: GM Research Labs I came across the following letter in the December 1989 issue of Perspectives on Science and Christian Faith (The American Scientific Affiliation's Journal): " I am writing in response to the recent (December 1988) and lengthy review of Michael Denton's "Evolution: A theory in crisis". The reviewer, (T.E. Woodward) presented a very favorable account of a book whose claims to scholorship or integrity are woefully deficient. The book is praised as "an intellectual and spiritual delight," a forceful critique," and a "careful historical review." Furthermore, the impression is given that informed reviews likewise share the same positive appraisal. I take serious objection to all these points. To start in reverse order, five out of seven reviews I could obtain in my university library pointed out the serious errors of logic, synedoches, direct misquotes, gross factual mistakes, and even spelling errors in Denton's book. The only slightly positive comments came from the "Parabola" - an eastern mysticism journal - and from Stephen Rose who approved the critique of the path of avian evolution of flight even though he acknowledged the serious errors and oversimplifications in the book. Why are all these reviewers so irate? Basically, the same old creationist tactics and ill-founded objections. Consider Denton's facile explanation of why evolution - the object of critique is macroevolution - is accepted by the scientific community: the "priority paradigm." This Kuhnian notion (already problematic in Kuhn's own work) is given the sole task of founding Denton's protrayal of a theory in "crisis" which is nevertheless not abandoned. Denton's lack of precision - he conflates natural selection with chance - and expertise is also evident in his treatment of technical disputes within biology. These include the punctuationalists' attempts to decouple macroevolution from microevolution, the cladist attack on Darwinian phylogenes, Kimura's neutralism and discussions of the paths of evolution (such as avian flight). The standard creationist tactic consists of "research by exegesis" or eisogesis in this case; quotations from oponents in some minor technical dispute are judiciously chosen to make both positions seem untenable leaving agnosticism or creationism the only remaining alternatives. Denton's mishandling of these technical disputes enables him to conclude that there is no reason to believe that evolution of the higher taxa ever occurred. Denton unearths the typological perception of nature which was legitimately abandoned due to its lack of explanatory power. Denton proposes that all mammals are derived from a mammalian "archetype", fish from a fish archetype and so on. But how many archetypes will Denton need to account for the incredible diversity past and present species? Secondly how are these species "derived" and what are the limits to change since he allows for microevolution? Thirdly, how can this anachronistic typology account for the examples of species which are not rationally explainable in terms of types and constitute powerful evidence for the fact that evolution has occurred? Thus, whales with femurs, Archaebacteria, strange animals on Madagascar, marsupials, toothed birds, ..are either ignored or dismissed by some sleight of hand - see Denton's treatment of Archaeopterix. The whole discontinuous/continuous argument of Denton founders on his lack of precision and his failing to take into account significant research on the transitions between species or "types". Perhaps the best example of Denton's lack of intellectual acuity can be seen in his mishandling of molecular homologies. He confuses cousin-cousin relationships with ancestor-descendant relationships and comes up with the profound conclusion that both fish and humans are "equidistant" from lamprey. From the gross differences that both fish and mammals have from lamprey he fallaciously concludes that all vertebrate groups are equidistant from one another. The remarkable agreement of molecular data with traditional evolutionary phylogenies beggars description. There is no reason why humans need to be more closely related to chimpanzees than most other species of primates. Ironically, even Denton's diagrams of nested sets point to the hierarchical nature of taxonomy (already derived from paleontology and comparative anatomy) which is yet another line of evidence for the fact of evolution. Denton's major flaws lie in his scholarship and integrity. Firstly, his citations of leading biologists often distort and twist their intent (his discussion on taxonomy where he makes Halstead sound like a cladist!) Secondly he ignores arguments which he cannot criticize. Thus, key evidences for the fact of biological oddities and "imperfections," some of the better fossil transitions, comparative anatomy, biogeography, and the remarkable congruence of the geologic column with evolutionary hypotheses are not even addressed. On a personal note, I must confess to the surface persuasiveness of Denton's book. The selective treatment of evolutionary biology - focussed on difficult transitions and especially abiogenesis - and the impressive if fraudulent citations belie the true nature of the book's argument. On a second and more perspicacious reading I was at first disappointed and then finally infuriated by the unsustainable attacks on evolution and the even more repulsive misuse of sources. Denton rightly belongs with other misbegotten attacks on evolution such as Ian Taylor's "In the minds of men" - their popularity is inversely proportional to the biological or historical knowledge of their readers. Unfortunately the desire to see evolution refuted often grants evolution's critics a prior claim to truth. If we should go about refuting evolution it will require sound arguments and careful scholarship; nothing less is worthy of the evangelical community. Marvin Keuhn 48 Carling Street #1 Hamilton, Ontario L8S 1M9 Canada " -- Don D.C.Lindsay Carnegie Mellon Computer Science =================================================================== From: Ken Smith To: All Msg #128, Jul-29-93 04:29PM Subject: Re: A couple of points from a non-evolutionary scientist Organization: Maths, University of Queensland From: kgs@maths.uq.oz.au (Ken Smith) Message-ID: Newsgroups: talk.origins In article <1993Jul27.140759.26083@st-andrews.ac.uk> mrl@st-andrews.ac.uk ( Michael Ladomery) writes: >In article <1993Jul26.094125@IASTATE.EDU> danwell@IASTATE.EDU (Daniel A >Ashlock) writes: > >[some hints to Denton's book] > >This reminds me of a recent seminar I attended here at St Andrews >given by a Creationist. > >A lot of the seminar was devoted to Denton's book. >A slide was shown which essentially depicted the similarities >between the (globin I think) protein sequences of various >vertebrates and (if I remember correctly) some proto-chordate >species. The protein comparisons indicated a rough equality of >values. > >However: these values corresponded to comparisons with >the proto-chordate in a "vertical" not "horizontal" sense >if you see what I mean. There was no info. about the actual >distances between say man and chimp, but only about the >similarity to the arbitrary reference. > >Clearly that was misleading. > >Moreover, when challenged, the gentleman giving the seminar >did not know- > >the difference between protein and DNA comparisons >the meaning of third postion variation (nb degeneracy of the code) >the nature of a conservative substitution in a peptide sequence. > >That just about says it all frankly. I don't normally get involved in discussions about biological topics since my training and knowledge lie in the physical sciences area. However since Denton has been raised again, and his writings about phylogenetic trees are apparently being used by creationists who neither know nor understand any significant amount about molecular biology, a brief refutation of some of Denton's work where it impinges on mathematical analysis of phylogenetic trees is worth while. Quotations are from Denton's _Evolution: A Theory in Crisis_ Burnett Books, London, 1985. On page 284 he produces a list of protein sequence differences between a lamprey and some other species. It reads (numbers are percent): lamprey -- carp (fish) 75 lamprey -- frog (amphibian) 81 lamprey -- chicken (bird) 78 lamprey -- kangaroo (marsupial) 76 lamprey -- human (placental) 73 He then writes: There is not a trace at a molecular level of the traditional evolutionary series: cyclostome --> fish --> amphibian --> fish --> reptile --> mammal. Incredibly, man is as close to lamprey as are fish! None of the higher jawed vertebrate groups is an [sic] any sense intermediate between the jawless vertebrates and other jawed vertebrate groups. The words "man is as close to lamprey as are fish" have a very familiar ring to creationist watchers! Now construction of phylogenetic trees from molecular data is a non-trivial mathematical problem. However, in this case, unless everything I have learned about molecular biology is wrong, the following tree agrees with the above data! ancestral organism /\ / \ / \ / \ / \ /\ \ / \ \ / \ \ / \ \ /\ \ \ / \ \ \ / \ \ \ / \ \ \ / \ \ \ /\ \ \ \ / \ \ \ \ / \ \ \ \ / \ \ \ \ / \ \ \ \ /\ \ \ \ \ / \ \ \ \ \ / \ \ \ \ \ / \ \ \ \ \ / \ \ \ \ \ / \ \ \ \ \ / \ \ \ \ \ human kangaroo chicken frog carp lamprey Denton's third last paragraph in the chapter in which he discusses biochemistry reads (on page 306): Despite the fact that no convincing explanation of how random evolutionary processes could have resulted in such an ordered pattern of diversity, the idea of uniform rates of evolution is presented in the literature as if it were an empirical discovery. The hold of the evolutionary paradigm is so powerful that an idea which is more like a principle of medieval astrology than a serious twentieth-century scientific theory has become a reality for evolutionary biologists. As I said, I am no biologist. But the differences between the lamprey and the other organisms listed are the sum of the molecular changes from the last common ancestor (labelled "ancestral organism" above) and the vertebrate under consideration, and that from the ancestor to the lamprey. Since these are all about the same, there must have been about the same changes in all lines of descent from the ancestor. In other words, contrary to Denton's claim, molecular changes proceed at roughly uniform rates! I'll leave it to biologists to comment on other blunders found in Denton. Ken Smith


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