Saturday, February 12, 2005

Haeckel

Haeckel:

To recapitulate:


1) Wilhelm His is not necessarily a reliable source of information regarding the scientific status of Haeckel's work. He and Haeckel were openly hostile to each other his opinion could hardly be considered unbiased. And some have questioned the accuracy of His's drawings as well.

2) There is no historical documentation for Haeckel having ever been tried much less convicted of fraud. This story appears to be a myth.

3) While it is technically correct that humans and other terrestrial vertebrates do not posses "gills" as embryos, they do posses structures that appear to be homologous in great detail to the structures of fish embryos that develop into gills. The recognition of this fact is not dependant on the acceptance of evolution. However the retention of these gill-like structures in the embryological development of terrestrial vertebrates is best explained by descent with modification from a fish-like ancestor.

4) The evidence from embryology (such as the existence of pharyngeal pouches) is not in any way dependant on Ernst Haeckel or his drawings, fraudulent or not. Or as Michael Richardson put it:

On a fundamental level, Haeckel was correct: All vertebrates develop a similar body plan (consisting of notochord, body segments, pharyngeal pouches, and so forth). This shared developmental program reflects shared evolutionary history... Haeckel's inaccuracies damage his credibility, but they do not invalidate the mass of published evidence for Darwinian evolution. (Richardson et al. 1998, p. 983-984)

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Haeckel

Haeckel:

To recapitulate:


1) Wilhelm His is not necessarily a reliable source of information regarding the scientific status of Haeckel's work. He and Haeckel were openly hostile to each other his opinion could hardly be considered unbiased. And some have questioned the accuracy of His's drawings as well.

2) There is no historical documentation for Haeckel having ever been tried much less convicted of fraud. This story appears to be a myth.

3) While it is technically correct that humans and other terrestrial vertebrates do not posses "gills" as embryos, they do posses structures that appear to be homologous in great detail to the structures of fish embryos that develop into gills. The recognition of this fact is not dependant on the acceptance of evolution. However the retention of these gill-like structures in the embryological development of terrestrial vertebrates is best explained by descent with modification from a fish-like ancestor.

4) The evidence from embryology (such as the existence of pharyngeal pouches) is not in any way dependant on Ernst Haeckel or his drawings, fraudulent or not. Or as Michael Richardson put it:

On a fundamental level, Haeckel was correct: All vertebrates develop a similar body plan (consisting of notochord, body segments, pharyngeal pouches, and so forth). This shared developmental program reflects shared evolutionary history... Haeckel's inaccuracies damage his credibility, but they do not invalidate the mass of published evidence for Darwinian evolution. (Richardson et al. 1998, p. 983-984)

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Saturday, January 15, 2005

Icons of ID: (Peppered moth) Bruce Grant letter to Pratt Tribune

Another foremost expert on the pepper moth is Bruce Grant. In 2000, Bruce Grant wrote a letter to the Editor of the Pratt Tribune Archives

In a now classic paper called Fine Tuning the Peppered Moth Paradigm published in Evolution 53 (3), 1999, pp. 980-984, Bruce Grant concludes:

Industrial melanism in peppered moths remains one of the best documented and easiest to understand.


The following is the text of the letter to the editor



Charges of fraud misleading


Letter to the Editor Pratt Tribune, December 13, 2000

In recent weeks your newspaper has printed letters debating revisions in high school biology curricula. Some of the correspondents have leveled charges of fraud directed at evolutionists for attributing changes in the colors of peppered moths to natural selection. As I am one of the evolutionary biologists who study peppered moths, I feel obliged to comment. Charges of fraud cannot be left unchallenged.



Some background about peppered moths is necessary. The common form of this moth species is pale gray. About 150 years ago, a black specimen was discovered near an industrial city in England. Over the years, the black (melanic) form became ever more common as the pale form became rare. By 1900 the black form exceeded 90 percent in peppered moth populations throughout the industrialized regions of England. The phenomenon was dubbed industrial melanism.



Because people knew that birds eat insects, scientists as early as 1896 suspected that birds were eating the different color forms of peppered moths selectively based on their degree of conspicuousness in habitats variously blackened by industrial soot. Extensive experimental work supports this view, although questions remain. Other scientists proposed that moths responded to the presence of pollutants by developing darker body colors. We now know from genetic analysis that the colors of adult peppered moths are determined by genes; thus, the changes in the percentages of pale to black moths over generations reflect changes in the genetic makeup of moth populations.



As industrial practices have changed in many regions, we have observed black moths plummet from 90 percent to 10 percent in the just the past few decades. Once again, we have observed significant genetic changes occur in moth populations. Evolution is defined at the operational level as genetic change over time, so this is evolution. Of the several factors known to produce evolutionary change, only natural selection is consistent with the patterns of the changes we see occurring in moth populations. Evolution examined at this level is as well established as any fact in science.



We still have work to do. We do not all agree about the relative roles of contributing factors, such as the flow of genes between moth populations in different regions, the importance of lichens on trees, where on trees moths might hide from predators, how important is differential predation, and so on. As in any branch of science, participants endlessly debate interpretations. Such wrangling is the norm, and it stimulates additional research. That is how we make progress.



Our debates have never been secret. For recent overviews of the controversies, please see FINE TUNING THE PEPPERED MOTH PARADIGM or www.els.net/elsonline/html/A0001788.html . Yet, unwarranted charges of fraud, fakery and cover-ups repeatedly appear in letters printed in newspapers. In your paper, Ms. Katrina Rider "asserts" the peppered moth story is a hoax. She conveys the impression that dead moths were glued to trees as part of a conspiracy of deception. She seems unaware that moths were glued to trees in an experiment to assess the effect of the density (numbers) of moths on the foraging practices of birds. Taken out of the context of the purpose of the experiment, the procedure does sound ludicrous.



But, should we blame Ms. Rider for her outrage upon learning that moths were glued to trees? No. Instead, I blame Dr. Jonathan Wells, who wrote the article she cites as her source of information. While he has done no work on industrial melanism, he has written opinion about the work. To one outside the field, he passes as a scholar, complete with Ph.D. Unfortunately, Dr. Wells is intellectually dishonest. When I first encountered his attempts at journalism, I thought he might be a woefully deficient scholar because his critiques about peppered moth research were full of errors, but soon it became clear that he was intentionally distorting the literature in my field. He lavishly dresses his essays in quotations from experts (including some from me) which are generally taken out of context, and he systematically omits relevant details to make our conclusions seem ill founded, flawed, or fraudulent. Why does he do this? Is his goal to correct science through constructive criticism, or does he a have a different agenda? He never mentions creationism in any form. To be sure, he sticks to the scientific literature, but he misrepresents it. Perhaps it might be kinder to suggest that Wells is simply incompetent, but I think his errors are by intelligent design.



Bruce Grant



Professor of Biology

College of William and Mary

Williamsburg, Virginia

Source:Icons of Evolution by Jonathan Wells CRITICAL REVIEWS, LETTERS, AND ESSAYS

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Saturday, January 08, 2005

Icons of ID: (Finches) David Wisker's Jonathan Wells and Darwin's Finches

Jonathan Wells and Darwin's Finches by Dave Wisker

In Chapter 8 of Icons of Evolution, Jonathan Wells examines the case of "Darwin's Finches", and claims that textbooks exaggerate not only the importance of the finches to Darwin's thinking, but also the evidence that they are an excellent example of evolution in action. He also accuses biologists Rosemary and Peter Grant, who spent 30 years studying these birds, of exaggerating the evidence as well. As we shall see, Wells's case is weak. Darwin's Finches remain one of the best examples of adaptive radiation in the literature of evolutionary biology.

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Icons of ID: (General) Nic Tazmek's Icons of Obfuscation

Icon of Obfuscation Jonathan Wells's book Icons of Evolution and why most of what it teaches about evolution is wrong

Introduction

Jonathan Wells's book Icons of Evolution: Science or Myth? Why Much of What We Teach About Evolution Is Wrong (henceforth Icons) makes a travesty of the notion of honest scholarship. Purporting to document that "students and the public are being systematically misinformed about the evidence for evolution," (p. XII) via common textbook topics such as peppered moths, embryo similarities, and fossil hominids [2], Icons in fact contains a bevy of its own errors. This is not original -- creationists have been making mistakes about evolution for years. Newly and more insidiously, however, Icons contains numerous instances of unfair distortions of scientific opinion, generated by the pseudoscientific tactics of selective citation of scientists and evidence, quote-mining, and "argumentative sleight-of-hand," the last meaning Wells's tactic of padding his topical discussions with incessant, biased editorializing. Wells mixes these ingredients in with a few accurate (but always incomplete) bits of science and proceeds to string together, often in a logically arbitrary fashion, a narrative that is carefully crafted to make the semblance of an honest case for Wells's central defamatory accusation: that mainstream biologists are "dogmatic Darwinists that misrepresent the truth to keep themselves in power" (pp. 242-243).

This essay will show that it is Wells's book Icons that is shot through with misrepresentations.

The central pillar of Wells's case is this:

"Some biologists are aware of difficulties with a particular icon because it distorts the evidence in their own field. When they read the scientific literature in their specialty, they can see that the icon is misleading or downright false. But they may feel that this is just an isolated problem, especially when they are assured that Darwin's theory is supported by overwhelming evidence from other fields. If they believe in the fundamental correctness of Darwinian evolution, they may set aside their misgivings about the particular icon they know something about." (Icons, pp. 7-8)


In other words, Wells argues that the specialists know about the problems in their field of expertise, but that everyone thinks that the evidence supporting evolution is somewhere else. This is just plain false, as we shall see -- the experts in each field have explicitly stated that the evidence in their field supports evolutionary theory, and further they have supported their statements with evidentiary arguments. If Wells's contention about the experts is false, then Wells's argument collapses. Wells likes asking questions; it is now time for him to answer some.

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Icons of ID: (Peppered moth) Majerus commenting on Wells

Majerus, one of the foremost experts on the peppered moth has given a Darwin Lecture, 'The Peppered Moth: Decline of a Darwinian Disciple', to the British Humanist Society on 12 February 2004
Hooper’s book, Of Moths and Men is so littered with errors, misrepresentations, misinterpretations and falsehoods that it is impossible to innumerate them all here. The writings of Wells and some of the other critics of the peppered moth story are similarly plagued. However, they cannot be simply dismissed, as many of the readers of these critics are not armed with the knowledge of evolutionary biology, genetics and ecological entomology necessary to perceive the errors and manipulations within these works. Their writings are lively and readable, and their arguments can be persuasive to those with limited or no training in evolutionary genetics or entomology. Furthermore, few of their readers will have the time to refer to original and review papers on the peppered moth written by those who have worked with the peppered moth, to judge the veracity of the words of people such as Hooper and Wells.
Source: The Peppered moth: decline of a Darwinian disciple

See also this powerpoint presentation

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Icons of ID: (Cambrian Explosion) And the Wedge continues

The Discovery Institute continues to ignore the advice of Richard Colling


Prof. Richard Colling:
In his new book, “Random Designer,” he writes: “It pains me to suggest that my religious brothers are telling falsehoods” when they say evolutionary theory is “in crisis” and claim that there is widespread skepticism about it among scientists. “Such statements are blatantly untrue,” he argues; “evolution has stood the test of time and considerable scrutiny. [1]”

Sharon Begley in Tough Assignment: Teaching Evolution To Fundamentalists, Wall Street Journal, December 3, 2004; Page A15


On October 11, 2004, the Grantsburg School board passed the following resolution


Motion C. Erickson/D. Ahlquist to revise the Science Curriculum Resolution (from June 2004) as follows, “When theories of origin are taught, students will study various scientific models/theories of origins and identify the scientific data supporting each.” Motion carried 6-0.



After receiving letters from more than 300 educators and 43 deans of Wisconsin Universities, the board revised their position


“ Students are expected to analyze, review, and critique scientific explanations, including hypotheses and theories, as to their strengths and weaknesses using scientific evidence and information. Students shall be able to explain the scientific strengths and weaknesses of evolutionary theory. This policy does not call for the teaching of Creationism or Intelligent Design.” Motion carried 6-1. Ahlquist opposed.


The DI released the following press release titled "Wisconsin School Board Adopts Improved Policy Endorsing Fully Teaching Evolution, Not Creationism". It is good to realize that the DI staff seems to include Intelligent Design in 'Creationism'. Truth in advertising I'd say...




Cooper noted that there are now hundreds of scientists who are raising criticisms of modern evolutionary theory, also known as "neo-Darwinism."

"If scientists can debate neo-Darwinism on scientific grounds," he asked, "what's wrong with students learning about some of these debates in biology class?"


Especially when ID proponents and Discovery Insitute Staff are presenting these criticisms as if there is a fundamental problem with evolutionary theory or that neo-Darwinism is flawed when in fact in most cases these scientists are arguing the opposite.

And the Wedge continues, sadly enough the victims seem to be once again science and religion.
The only hope is that students will learn what is wrong with ID proponents' portrayal of these supposed 'criticisms'. Imagine however the cost to science and religious faith... Imagine the impact of finding out that contrary to ID claims irreducibly oomplex systems can evolve? Imagine the impact of finding out that contrary to ID claims the design inference is fundamentally flawed? Imagine the impact of finding out that contrary to ID claims "No Free Lunch" theorems do not support a design inference? And imagine the cost of students finding out that contrary to the claims by ID proponents, the Cambrian period is not a problem for neo-Darwinian theory?

Valentine, an expert on the Cambrian explosion, author of "On the origin of phyla" and often quoted by ID proponents who suggest that the Cambrian explosion is a problem for neo-Darwinian theory writes:


Valentine:
The title of this book, modeled on that of the greatest biological work ever written, is in homage to the greatest biologist who has ever lived. Darwin himself puzzled over but could not cover the ground that is reviewed here, simply because the relevant fossils, genes, and their molecules, end even the body plans of many of the phyla, were quite unknown in his day. Nevertheless, the evidence from these many additional souces of data simply confirm that Darwin was correct in his conclusions that all living things have descended from a commmon anscestor and can be placed within a tree of life, and that the principle process guiding their descent has been natural selection.

Valentine On the Origin of Phyla 2004: Preface


Imagine the 'surprise' when it is shown that intelligent design has no viable scientific theory to explain evolution? Imagine the surprise when children are told about the findings by Ryan Nichols

Ryan Nichols is the author of Scientific content, testability, and the vacuity of Intelligent Design theory The American Catholic philosophical quarterly , 2003 , vol. 77 , no 4 , pp. 591 - 611,


In my argument against Intelligent Design Theory I will not contend that it is not falsifiable or that it implies contradictions. I’ll argue that Intelligent Design Theory doesn’t imply anything at all, i.e. it has no content. By ‘content’ I refer to a body of determinate principles and propositions entailed by those principles. By ‘principle’ I refer to a proposition of central importance to the theory at issue. By ‘determinate principle’ I refer to a proposition of central importance to the theory at issue in which the extensions of its terms are clearly defined.
I’ll evaluate the work of William Dembski because he specifies his methodology in detail, thinks Intelligent Design Theory is contentful and thinks Intelligent Design Theory (hereafter ‘IDT’) grounds an empirical research program. Later in the paper I assess a recent trend in which IDT is allegedly found a better home as a metascientific hypothesis, which serves as a paradigm that catalyzes research. I’ll conclude that, whether IDT is construed as a scientific or metascientific hypothesis, IDT lacks content.



or Patrick Frank?

Patrick Frank is the author of "On the Assumption of Design]", Theology and Science, Volume 2, Number 1 / April 2004, pp. 109 - 130.


Abstract: The assumption of design of the universe is examined from a scientific perspective. The claims of William Dembski and of Michael Behe are unscientific because they are a-theoretic.

...

Finally, the argument from the unlikelihood of physical constants is vitiated by modern cosmogonic theory and recrudesces the God-of-the-gaps.



Is it worth it? It's a great opportunity for the truth to get out though.

Send your comments to Grantsburg Board of education members


David Ahlquist dahlquist@grantsburg.k12.wi.us
David Dahlberg ddahlberg@grantsburg.k12.wi.us
Christine Erickson cerickson@grantsburg.k12.wi.us
Russell Erickson rerickson@grantsburg.k12.wi.us
Cindy Jensen cjensen@grantsburg.k12.wi.us
Eric McKinley emckinley@grantsburg.k12.wi.us
James Sundquist jsundquist@grantsburg.k12.wi.us


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Icons of ID: (Cambrian Explosion) Darwinian predictions and the Cambrian

Original Publication
Common, though persistent, misconceptions exist among ID proponents about the Cambrian Explosion, the Darwinian 'tree of life' and the appearance of phyla. I hope that my contribution will help put to rest some of these misconceptions.

These misconceptions include: 1) no Pre-Cambrian fossils 2) appearance of phyla are at odds with Darwinian predictions 3) the shape of the tree of life over time 4) no transitional fossils between phyla.

The confusion seems to have started with Art Battson, was popularized by Wells but continues with on Mark Hartwig and more recently with Salvador who posted the following picture (loosely based on the original work by Art Battson).




There are several significant problems with this picture. Lets start with the top left graph which shows the 'Darwinian prediction' for the origin of phyla. Looking at the bottom left figure, one notices that Darwin accepted extinctions and thus the suggestion that a 'Darwinian prediction' should be on of a continuously increasing number of phyla is wrong. The second problem is that the concept of phyla did not exist in Darwin's time [1] and that Darwin was talking about the origin of species not necessarily higher taxa. Another problem is that Darwinian theory does not state anything about the speed with which phyla should arise.

Additionally, the top right picture which supposedly represents the actual data is misleading due to the compressed time scale and the discontinuities. The real question is: Is the origin of phyla at odds with Darwinian theory. As I will show, it isn't.

The most problematic claim is that Darwinian theory predicts that phyla would arise as portrayed above. No evidence is provided as to how this prediction was made or derived. In fact I will show that the prediction is a strawman? By innappropriately comparing species trees (Darwin) with a Linnean hierarchy (phyla) a prediction is made that Darwin expected lower taxa to evolve into higher taxa. In otder to understand why this perspective is erroneous it is helpful to understand what the Linnaean hierarchy is all about/ While the Linnean concept of using nested hierarchies is compatible with an evolutionary perspective, a Linnaean categorization inevitably imposes equal distance to organisms in each category. Which means that a comparison between a Linnean hierarchy and an evolutionary tree can lead to misleading conclusions.

Linnaean Hierarchy



A good review paper on the Linnaean hierarchy and its importance versus other proposed phylogeny based hierarchies is Stems, nodes, crown clades, and rank-free lists: is Linnaeus dead? by Michael Benton in Biol. Rev. (2000), 75, pp. 633-648. A good essay which looks at the Linnean hierarchy and a recent proposal called Phylocode is 'The future of biological taxonomy? Does the PhyloCode offer a viable alternative to traditional Linnaean taxonomy?' by Jake Alexander.


As I have already shown the Linnaean hierarchy is artificial and indeed has been subject itself to many changes. While most biologists accept the concept of 'species' as real, higher taxa are less well defined.


Formally, there is limited advice about how to define taxa above the species level, such as genera, families, or orders, although in practice all systematists have used diagnoses consisting of characters.


That Linnaean nomenclature is articificial is shown by the various modifications made since Linnaeus first proposed his hierarchy.


Linnaean nomenclature has been modified both before the advent of cladistics (e.g. exclusion of polphyletic taxa, insertion of additional category terms, inclusion of fossil taxa), and after (e.g. exclusion of paraphyletic taxa, use of indented lists, sequencing, plesions). All these modifications have shared a common principle : that classifications should adhere ever closer to current knowledge of phylogeny, while at the same time remaining conservative.
Stems, nodes, crown clades, and rank-free lists: is Linnaeus dead? by Michael Benton in Biol. Rev. (2000), 75, pp. 633-648


In other words, these classifications are human constructs and no true classification exists:


Biological classifications, then, are necessarily entirely human constructs. There is no single, true classification inherent in Nature that is there to be discovered. In this paper, I use the term ` classification' in two ways, as is common practice: first, a classification means an ordered list of species or higher taxa, and second, classification describes the process of achieving such an ordered list. The usages should be clear from context.
Stems, nodes, crown clades, and rank-free lists: is Linnaeus dead? by Michael Benton in Biol. Rev. (2000), 75, pp. 633-648



The Linnaean hierarchy is a hierarchy of taxonomic categories. It should not be confused with a hierarchy of taxa, the members of which may (or may not) be assigned to those categories. Therefore, even if taxonomic categories (kingdom: division/phylum: class: order: family: genus: species) were to be eliminated, hierarchies of nested taxa (Animalia: Chordata: Aves: Anseriformes: Anatidae: Branta: B. canadensis) presumably would not also be eliminated - at least not under an evolutionary world view. Regardless of the Linnaean hierarchy, the principle of common descent implies that the relationships among taxa will be nested and hierarchical.




The concept of a 'phylum' is an arbitrary division, or classification of a group of organisms. The moment you define a particular species under the Linaean hierarchy, you have to define its genus, family, order, class, phylum and kingdom. So contrary to some of the claims of ID, higher taxa arise first in a Linnaean hierarchy. But that's because of the somewhat arbitrary and artificial nature of this hierarchy.

Because of these issues people over time has proposed (better) alternatives. In Proposal for a standardized temporal scheme of biological classification for extant species John Avise and Glenn Johns, propose ways to rectify the nomenclature of biological classifications.


The Linnaean system of classification (3) has served biologists for more than two centuries. Originally designed to catalogue diverse works of the Creator, the hierarchical categories in this ordering scheme later became interpretable as natural outcomes of the nested branching structures in evolutionary trees. Yet most classifications in current use continue to group species according to some unspecified mix of similarity by resemblance (phenetic grades) and similarity by descent (phyletic clades). Apart from this epistemological flaw, the kinds of empirical data used to recognize grades or clades vary greatly among organismal groups, with no explicit attempt to normalize assayed characters, to equilibrate taxonomic assignments, or even to adopt any universally standardized criteria for taxonomic ranking (4, 5).
Proposal for a standardized temporal scheme of biological classification for extant species by John Avise and Glenn Johns in Proc Natl Acad Sci U S A. 1999 June 22; 96 (13): 7358–7363


Based on the shortcomings of the Linnaean hierarchy, people have proposed PhyloCode. The advantage of PhyloCode is that it references phylogeny, the disadvantage is that this nomenclature is far less universal and stable than the Linnaean nomenclature. Not surprisingly the PhyloCode is not without its critics.


Linnaean nomenclature is stable enough to say what we know, flexible enough to accommodate what we learn; independent of specific theory, yet reflective of known empirical data; compatible with phylogenetic theory, but not a slave to it; particular enough for precise communication, general enough to reflect refuted hypotheses. LN is an effective international, inter-generational, and trans-theoretical system of classification that was forged and tested by those describing the earth's biota, not touting political slogans. It has weathered more worthy adversaries than the Phylocode and will be in wide use long after the latter is a curious footnote to the history of taxonomy."



and this one and hotly discussed on this TaxaCom archive



Shortcomings of Conventional Taxonomic Practice A primary limitation of conventional taxonomy is that extant taxa placed at the same Linnaean rank are not necessarily equivalent in age, diversity, disparity, or any other consistent property of their biology or evolutionary histories. Current taxonomic anachronisms communicate almost no information as to whether, for example, a rank such as genus, tribe, family, or order in mammals is equivalent to its counterpart rank in fishes, insects, or any other assemblage. Thus, the ranks in current use do little to aid, and indeed often may hinder, comparative evolutionary studies.
Proposal for a standardized temporal scheme of biological classification for extant species by John Avise and Glenn Johns in Proc Natl Acad Sci U S A. 1999 June 22; 96 (13): 7358–7363




(Click image to enlarge) Fig. 1 Examples of gross disparities of taxonomic assignments in current classifications. The phylogenies depicted, based on an integration of molecular and paleontological evidence, come from information in refs. 43 (a), 26 (b), and 44 (c). Proc Natl Acad Sci U S A. 1999 June 22; 96 (13): 7358–7363


The authors propose an alternative


Proposal for a Standardized Classification Scheme We propose that the approximate dates of nodes in evolutionary trees should be the universal criterion according to which taxonomic classifications above the level of biological species are erected. Decisions about the particular window of time to be associated with each taxonomic rank are arbitrary, but the conventions adopted should reflect some agreed-to consensus (7) among practicing systematists reaching this initial consensus may be the most difficult part of the entire endeavor).


Under this alternative the species of the Ciclids, primates and fruit flies would be placed in a hierarchical taxonomy as follows



(Click image to enlarge) Fig.3 The temporal-banding concept as applied to produce a time-standardized classification for the three groups of organisms in Fig. 1. Proc Natl Acad Sci U S A. 1999 June 22; 96 (13): 7358–7363




The shortcoming identified by these authors is also exemplified by the arguments by ID proponents as to the nature of the evolutionary tree. Once phyla arose, they are often portrayed as remaining 'frozen' in diversity, disparity or morphological distance.

Darwinian theory and the fossil evidence



As I said before: "While the Linnean concept of using nested hierarchies is compatible with an evolutionary perspective, a Linnaean categorization inevitably imposes equal distance to organisms in each category. Which means that a comparison between a Linnean hierarchy and an evolutionary tree can lead to misleading conclusions".

A good example can be observed in the following graph:



Origin of phyla



Most recently, the DI Staff (DIS) (remember that they are arguing that origin of phyla etc is at odds with (Neo-)Darwinian theory, citing Valentine. Valentine is commonly cited by ID proponents and one may infer that the DIS agrees with Valentine's interpretations:


DIS
More recently, in his 2004 book On the Origin of Phyla, paleontologist James Valentine evaluates various attempts to explain (or explain away) the origin of the body plans that arise in the Cambrian. He concludes that no current hypothesis provides a satisfactory account of the origin of the Cambrian phyla and that the problem of novel body plans remains unsolved—or, as he puts it “the underlying causes remain uncertain.”


versus


The title of this book, modeled on that of the greatest biological work ever written, is in homage to the greatest biologist who has ever lived. Darwin himself puzzled over but could not cover the ground that is reviewed here, simply because the relevant fossils, genes, and their molecules, end even the body plans of many of the phyla, were quite unknown in his day. Nevertheless, the evidence from these many additional souces of data simply confirm that Darwin was correct in his conclusions that all living things have descended from a commmon anscestor and can be placed within a tree of life, and that the principle process guiding their descent has been natural selection.

The data on which this book is based have accumulated over the nearly century and a half since Darwin published On the Origin of Species, some gradually, but much in a rush in the last several decades. I have been working on this book for well over a decade, and much of that time has been spent in trying to keep up with the flood of incredibly interesting findings reported from outcrops and laboratories. I am stopping now not because there is a lull in the pace of new discoveries (which if anything is still picking up), but because there never will be a natural stopping place anyway, and because the outlines of early metazoan history have gradually emerged from mysteries to testable hypotheses.
Valentine On the origin of phyla 2004, preface


The book by Valentine is a whopping 500+ pages but one would expect the DIS to at least have read the preface to the book.

Valentine hase been extensively quoted within ID's Valentine on the Cambrian. One may wonder why Valentine's more recent findings have not found their way onto this website.

PZ Myers discusses the 'scholarship' when DI describes the work by Valentine and others on the Cambrian explosion. In addition to relying on old papers, especially since in the last decade new fossils and phylogenetic data have added much to our knowledge of the Cambrian explosion, the DI seems to focus on 'sound bites' while missing the larger picture.


Darwin on his 'tree of life'




The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. The green and budding twigs may represent existing species; and those produced during each former year may represent the long succession of extinct species. At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have tried to overmaster other species in the great battle for life. The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was small, budding twigs; and this connexion of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear all the other branches; so with the species which lived during long-past geological periods, very few now have living and modified descendants. From the first growth of the tree, many a limb and branch has decayed and dropped off; and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state.



Click picture for larger version



I request the reader to turn to the diagram illustrating the action, as formerly explained, of these several principles; and he will see that the inevitable result is that the modified descendants proceeding from one progenitor become broken up into groups subordinate to groups. In the diagram each letter on the uppermost line may represent a genus including several species; and all the genera on this line form together one class, for all have descended from one ancient but unseen parent, and, consequently, have inherited something in common. But the three genera on the left hand have, on this same principle, much in common, and form a sub-family, distinct from that including the next two genera on the right hand, which diverged from a common parent at the fifth stage of descent. These five genera have also much, though less, in common; and they form a family distinct from that including the three genera still further to the right hand, which diverged at a still earlier period. And all these genera, descended from (A), form an order distinct from the genera descended from (I). So that we here have many species descended from a single progenitor grouped into genera; and the genera are included in, or subordinate to, sub-families, families, and orders, all united into one class. Thus, the grand fact in natural history of the subordination of group under group, which, from its familiarity, does not always sufficiently strike us, is in my judgement fully explained.

Chapter 13: On the origin of species

Darwin's tree in other words is fully in line with the expectations and the data. To see this consider the bottom species marked capital A-L. While in Darwin's graph they represent orders, they could equally well represent phyla. All these phyla by definition have to start at the bottom of the tree after the last common ancestor(s) until the species of those days had sufficiently diversified. In other words, that phyla arise at the bottom of the tree of life, is something easily overlooked. In this case, 12 phyla arose connected below with a common ancestor. So contraty to ID predictions, Darwinian theory is not accurately captured in the figure presented by Salvador.

Things do not get better though since the bottom right picture is again an oversimplification of the real tree of life. As Valentine shows, when taking into account the fossils and genetic knowledge of our times a picture emerges which is quite in line with Darwinian theory.


Linnaean Hierarchy

A Linnean hierarchy be definition has a species, genus, family, order, class, phylum and kingdom attached



  1. Levine, A., Review of Marc Ereshefsky, The Poverty of the Linnean Hierarchy, Quarterly Review of Biology, Spring, 2002.
  2. Brigandt, I. (2002) "The Linnean tradition under attack." Review of 'The Poverty of the Linnean Hierarchy. A Philosophical Study of Biological Taxonomy' by Marc Ereshefsky. Metascience 11: 355-358.



If we had understood modern evolutionary synthesis during Linnaeus’ time, it is possible we would not have adopted the “binomial” convention; we would have been influenced by the knowledge that phylogenetic groupings occur at variable levels and no two are strictly comparable. Thus, the point where one draws the line between a generic distinction and a familial distinction is more or less arbitrary and is unlikely to be consistent between different lineages:


Link

Common fallacies and misunderstandings



Common objections to the Cambrian explosion and the tree of life include the 'top-down/bottom-up' fallacy which is based on equivocation of two different kind of trees.


TOP-DOWN OR BOTTOM-UP

Some critics of evolution make much of the "top-down" versus the "bottom-up" pattern of appearance of higher taxa. That is, phylum-level diversity reaches its peak in the fossil record before class-level diversity, and the class-level diversity before that of orders, etc. These critics interpret this apparent "top-down" pattern as contrary to expectations from evolutionary theory. However, this pattern is generated by the way in which species are assigned to higher taxa. The classification system is hierarchical with species being grouped into ever larger and more inclusive categories. When this classification hierarchy is applied to a diversifying evolutionary tree, a "top down" pattern will automatically result. Consider species belonging to a single evolving line of descent given genus-level status. This genus is then grouped with other closely related lines of descent into a family. The common ancestors of these genera are by definition included within that family. Those ancestors must logically be older than any of the other species within the family. Thus the family level taxon would appear in the fossil record before most of the genera included within it. The "top down" pattern of taxa appearance is therefore entirely consistent with a branching tree of life. Keith Miller on Wells


and


Continuing to move the shells, Wells invokes a semantic sleight of hand in resurrecting a "top-down" explanation for the diversity of the Cambrian faunas, implying that phyla appear first in the fossil record, before lower categories. However, his argument is an artifact of taxonomic practice, not real morphology. In traditional taxonomy, the recognition of a species implies a phylum. This is due to the rules of the taxonomy, which state that if you find a new organism, you have to assign it to all the necessary taxonomic ranks. Thus when a new organism is found, either it has to be placed into an existing phylum or a new one has to be erected for it. Cambrian organisms are either assigned to existing "phyla" or new ones are erected for them, thereby creating the effect of a "top-down" emergence of taxa.
Gishlick ICONS OF EVOLUTION?\ Why much of what Jonathan Wells writes about evolution is wrong


Dawkins:


Suppose you have a great oak tree with huge limbs at the base and smaller and smaller branches toward the outer layers where finally there are just lots and lots of little twigs. Obviously the little tiny twigs appeared most recently. The larger boughs appeared a long time ago and when they did appear, they were little twigs. What would you think if a gardener said, "Isn't it funny that no major boughs have appeared on this tree in recent years, only small twigs?" You'd say he is stupid.
Richard DawkinsTHE "ALABAMA INSERT": A STUDY IN IGNORANCE AND DISHONESTY



Richard Dawkins, THE "ALABAMA INSERT": A STUDY IN IGNORANCE AND DISHONESTY Journal of the Alabama Academy of Science, Vol. 68, No.l, January, 1997. Franklin Lectures in Science & Humanities Auburn University April 1, 1996



Salvadore, I think you're incorrectly assuming that what Darwin wrote is somehow at odds with what Dawkins wrote. Dawkins' point is that phyla are named in retrospect, and they represent early branch points in evolution, some of which have left large groups of diverse survivors. More recent branch points, which have resulted in smaller amounts of divergence, naturally don't get categorized as the most inclusive kind of group (a phylum) when they belong to older, more inclusive groups. So anyone who asks the question, "why are there no new phyla", is failing to understand the basics behind phylogenetic classification. (The IDists didn't actually come up with this misunderstanding, they borrowed it from Stephen J. Gould. Between him and the creationists, I don't think IDists have ever come up with an original argument.)

All those pictures that you've posted have done is to take this misunderstanding and put it into visual form. There is no "Darwinian prediction" that new phyla should constantly arise; in fact, what you choose to call a "phylum" is arbitrary. We could call mammals a phylum if we wanted to, but then we'd have to call chordates a "super phylum" or some such. The charts also shows phyla arising straight out of the Cambrian without any change in morphology since. That's just laughable. Few modern animals resemble any Cambrian animal other than by having a few diagnostic characters that define their phylum. (And again, those diagnostic characters are determined in retrospect.) Check out the worm-like Pikaia, the Cambrian's representative chordate, and tell me how much it resembles an elephant or an ostrich:

Grape Ape at ARN


Although it has never been clear what hypotheses ID had in mind to explain the Cambrian explosion, it seems that when the veil of ignorance about the Cambrian Explosion is lifted, it appears to be well in line with the (neo-)Darwinian expectations. Has ID contributed in any manner to lifting this veil? On the contrary, only by representing the Cambrian Explosion as a strawman could ID even hope to make its case. And as is so common with arguments from ignorance, new data ended up showing ID to be wrong once again.


Salvador:
Let's try to be a little constructive about finding answers. I already admited it's a guess, and I think a fair one. I'm offering to you to tell every one what you think the graph should look like if you find that guess so disagreeable. If you are saying the guess is inaccurate, suggest what would be a better model.

Or is it that you'll have to admit, Darwinism never really gave predictions to begin with?


Interesting rhetoric, Salvador thinks the graph is a fair guess but seems unfamiliar with the writings of Darwin. IF he were correct and Darwinism never really gave predictions to begin with, then would the logical conclusion not be that the graph was 'made up'?
The real question, which the graph is trying to avoid by presenting a strawman, is : Is the data about phyla at odds with Darwinian theory. As I have shown it isn't.
The graph is a poor representation of factual data to promote a view of the Cambrian period which is at odds with the facts. And once again ID shows itself to be scientifically irrelevant, or in this case scientifically detrimental.



Salvador:
So to be fair, are you aware of whether Darwin or people making extrapolations of his theory, made any prediction about the increasing or decreasing of Phyla?

The most parsimonious interpretation (to me) is to assume that Darwinism predicted 1 phylum to start off with, and then that phylum became many. The graph of "Darwinian Predictions" reasonably depicts that idea.


Has it occured to Salvador to read what Darwin had to say about this? Remember that the concept of phyla did not exist in those days and that Darwin mostly focused on species (On the origin of Species). Nevertheless it is clear that Darwin does include extinction thus any graph which fails to take into account extinction is at odds with Darwin's work. I thought that Salvador was presenting a 'prediction', now it seems to be the 'most parsimonious interpretation'...

Salvador:
However, actual data does not yet agree with that view. It could be:

1. The transitionals existed, but we've just not found them

2. Some sort of Punctuated Evolution

3. Common descent is not how it happened

4. Something else

It's likely 4.: The view is wrong. ID presents a strawman argument and even their portrayal of actual morphological distance is erroneous. That ID has chosen to present a 'Darwinian prediction' based on 1) assumptions that are not clearly specified and in fact appear to be erroneous 2) ignorance of what Darwin actually wrote, shows once again that ID is scientifically without much merrit.

No pre-Cambrian fossils




When Charles Darwin wrote On the Origin of Species, he and most paleontologists believed that the oldest animal fossils were the trilobites and brachiopods of the Cambrian Period, now known to be about 540 million years old. Many paleontologists believed that simpler forms of life must have existed before this but that they left no fossils. A few believed that the Cambrian fossils represented the moment of God's creation of animals, or the first deposits laid down by the biblical Flood. Darwin wrote, "the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great," yet he expressed hope that such fossils would be found, noting that "only a small portion of the world is known with accuracy."

Since Darwin's time, the fossil history of life on Earth has been pushed back to 3.5 billion years before the present. Most of these fossils are microscopic bacteria and algae. However, in the latest Proterozoic - a time period now called the Vendian, or the Ediacaran, and lasting from about 650 to 540 million years ago - macroscopic fossils of soft-bodied organisms can be found in a few localities around the world, confirming Darwin's expectations
>Introduction to the Vendian Period


To learn more about Vendian fossils see Learning About the Vendian Animals or the exhibit at (the Paleontology Museum in Oslo (in Norwegian).

Disparity precedes divergence



Gould discussion


Gould pillories Walcott for his pragmatic inclusion of the Burgess Shale taxa into broadly defined phyla – ‘shoehorning’ in Gould’s terminology. But, here, Gould (also Mayr 2001, see p. 209) has forgotten a principle which is so fundamental it has become hackneyed: man classifies; nature does not. The only taxonomic rank possessing any degree of objective ‘reality’ is the species. To approximate disparity by counting phyla is to embark upon an extremely suspect enterprise.
Replaying Gould


and


Even if we confine ourselves to considering Phanerozoic animals, Gould is wrong. If we play Gould at his own game and approximate disparity by counting orders and higher taxonomic groupings (order and greater rank) within phyla, we find that:

* Brachiopoda achieve their maximum ‘disparity’ in the Devonian and Carboniferous periods;
* Mollusca in the Cretaceous;
* Echinodermata in the Ordovician;
* Hemichordata (if this is in fact a monophyletic group) in the Ordovician; and
* Chordata in the Carboniferous and Permian.

(Data after Rich et al. 1996.)
Replaying Gould



Finally, the pervasive pattern of geologic succession is systematically backwards from that predicted by the theory. Darwinian theory predicts that the gradual accumulation of minor evolutionary change and the increasing diversity of the lower taxa should ultimately produce the profound differences among the major body plans and the disparity of the higher taxa. Diversity should precede disparity. Geologic succession reveals the opposite: disparity precedes diversity. The major themes or body plans appear suddenly in the history of life only to be followed by variations on these pre-existing themes. The natural history of life on earth is systematically top to bottom, not bottom to top as Darwinian theory predicts.
Art Battson On the Origin of Stasis, Access Research Network Library File



The origin and differentiation of major clades is often assumed to have occurred in tandem with the ‘explosion’ of fossil evidence of diverse morphologies (‘disparity’) at the base of the Cambrian. Evidence is presented that this was not the case. Biogeographical and morphological differentiation among the earliest trilobites reveals incompleteness in the known early Cambrian record; similar evidence can be accrued for other major groups. Phylogenetic analysis proves the likelihood of ‘ghost’ lineages extending into the Precambrian. The important events in the generation of clades were earlier than the Cambrian ‘explosion’, at which time the groups become manifest in the fossil record. It is likely that the important phylogenetic changes happened in animals of small size; sister taxa of major groups are shown to be small animals. Decoupling cladogenesis from the Cambrian ‘explosion’ removes the necessity of
invoking unknown evolutionary mechanisms at the base of the Phanerozoic. Genes controlling development may have played a role in generating new morphologies, through heterochrony for example, in the early differentiation of metazoan body plans.
The Cambrian evolutionary ‘explosion’: decoupling cladogenesis from morphological disparity by R.A. Fortey, D.E.G. Briggs and M.A. Wills in Biological Journal of the Linnean Society (1996), 57: 13–33.







  1. The basic hierarchy as formulated by Linneus, is as follows: Imperium ("Empire"), Regnum ("Kingdom") Classis ("Class"), Ordo ("Order"), Genus, Species, Varietas ("Variety") . Over time 'Imperium' was dropped and variety lost much of its relevance. Two new ranks were added: phylum (between kingdom and class) and Family (between order and genus). The modern Linnaean System is based on a simple hierarchical structure in which organisms are sorted using the nomenclature of Kingdom, Phylum, Class, Order, Family, Genus and Species.


Other websites that use these graphics or similar arguments



Fossils Reject the "Tree of Life" at DarwinismRefuted.com

Casey Luskin et al Icons Haven't Lost Their Touch


Misleading: Regardless of what appears later in the fossil record, the bottom line is that almost all phyla appear in the Cambrian without any previous animal fossils to account for their supposed evolutionary origin.


ARN thread

Lots of examples

Origin of phyla

The Creation Debate: The Fossil Record -- Part One by Dr. John Ankerberg, Dr. Duane Gish, Dr. Kurt Wise

I believe that I may have located the orign of at last one of the graphs. It is from On the Origin of Stasis (Part I) By Art Battson found on ARN.



Darwinian Theory vs. the Fossil Record

Darwinian Theory attempts to explain the common ancestry of all species through the gradual transformation of major body plans. This theory is in opposition to the fossil evidence and the pervasive patterns of natural history.
An estimated 75 to 100 phyla appear explosively at the base of the Cambrian. Fossil evidence suggesting their common ancestry is not found in Precambrian rocks. A General Theory of Macrostasis is needed to explain the fossil data and the stability of the higher taxa.



The Fossil Evidence

Contrary to both Darwinian gradualism and punctuated equilibria theory, the vast majority of phyla appear abruptly with low species diversity. The disparity of the higher taxa precedes the diversity of the lower taxa.


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Friday, January 07, 2005

Icons of ID: (Cambrian Explosion) The Cambrian Explosion

Original Publication

Dembski's recent lamentations about what he considered the selective use of data by evolutionists (googlewars) motivated me to look in some more detail at how ID proponents are handling topics such as the Cambrian Explosion. My findings conclude that ID proponents are still confused about the Cambrian explosion, the fossil record, and the molecular data which contradicts their cartoonish portrayal of the Cambrian. Based on selective 'evidence' and poor scientific arguments, the impression is created that the Cambrian explosion is a problem for evolutionary theory or supportive of intelligent design. Neither assertion is true -- unless one accepts that Intelligent Design is all about ignorance. The lack of any scientifically relevant hypothesis by Intelligent Design to explain the Cambrian explosion exemplifies the scientific vacuity of ID, and I won't even mention the theological risks.

I was initially drawn to the Cambrian Explosion because Intelligent Design theorists had presented it as irrefutable proof of a designer. But after looking into the matter, it seems more like the Cambrian Explosion is a proving ground for evolutionary theory. Rather than a paucity of Precambrian fossil evidence, there is an abundance of it. Rather than throwing in the towel when faced with the rapid appearance of biological variation, scientists have come up with numerous theories explaining how the explosion of life could have happened. In all of this, I find myself disillusioned by the ID proponents. It seems that they too often distort the facts, or outright lie, to ‘prove’ their position. How can there ever be a valid search for truth if information is intentionally withheld or misrepresented?


Amen

Ironically Meyer argues that
When credible experts disagree about a controversial subject, students should learn about the competing perspectives.


The irony is that there are no credible experts who disagree and present a competing scientific perspective.

Or as Kevin Padian in The Talented Mr. Wells argues:


Ask how Wells and his colleagues will replace evolution with Intelligent Design, and where the peer-reviewed research for it is. Have them explain exactly who the Intelligent Designer is, exactly when and where He (She? It? They?) intervened in the history of the Earth and its life, and exactly how this can be shown to everyone’s satisfaction. Nobody here but us scientists? Then let’s make Intelligent Design a testable hypothesis and see how robust it is.



Meyer and Campbell write:


First, some scientists doubt the idea that all organisms have evolved from a single common ancestor. Why? Fossil studies reveal "a biological big bang" near the beginning of the Cambrian period (530 million years ago) when many major, separate groups of organisms or "phyla" (including most animal body plans) emerged suddenly without clear precursors. Fossil finds repeatedly have confirmed a pattern of explosive appearance and prolonged stability in living forms -- not the gradual "branching-tree" pattern implied by Darwin's common ancestry thesis. Discoveries in molecular genetics and embryology have also challenged universal common ancestry.


Controversy over life's origins Students should learn to assess competing theories San Francisco Chronicle Open Forum December 10, 2004

As usual with Meyer, it seems to be largely a rewrite of Meyer's Incorporate Controversy into the Curriculum Atlanta Journal Constitution, February 15, 2004

There are many problems with this statement. While I can appreciate the creationist interpretation given to these data by Meyer, a more scientific investigation quickly shows that there is little support for his position. Valentine, an expert on the Cambrian explosion, author of "On the origin of phyla" and often quoted by ID proponents writes:


Valentine:
The title of this book, modeled on that of the greatest biological work ever written, is in homage to the greatest biologist who has ever lived. Darwin himself puzzled over but could not cover the ground that is reviewed here, simply because the relevant fossils, genes, and their molecules, end even the body plans of many of the phyla, were quite unknown in his day. Nevertheless, the evidence from these many additional souces of data simply confirm that Darwin was correct in his conclusions that all living things have descended from a commmon anscestor and can be placed within a tree of life, and that the principle process guiding their descent has been natural selection.

The data on which this book is based have accumulated over the nearly century and a half since Darwin published On the Origin of Species, some gradually, but much in a rush in the last several dedades. I have been working on this book for well over a decade, and much of that time has been spent in trying to keep up with the flood of incredibly interesting findings reported from outcrops and laboratories. I am stopping now not because there is a lull in the pace of new discoveries (which if anything is still picking up), but because there never will be a natural stopping place anyway, and because the outlines of early metazoan history have gradually emerged from mysteries to testable hypotheses.

Valentine On the Origin of Phyla 2004: Preface


In fact (recent fossil) data as well as molecular genetic data do not support the creationist interpretation of Meyer et al.

Meyer, author of the The origin of biological information and the higher taxonomic categories. in Proceedings of the Biological Society of Washington 117, 213–239 is critically reviewed in the Paleontology Newsletter:


Many readily available papers that depart significantly from his conclusions are omitted without excuse, and the logic of his arguments is not always as tight as it should be. On the most general level, Meyer doesn’t understand the bare-bones mechanics of natural selection acting on ‘random’ variation.

The tainting of Proc. Biol. Soc. Wash. Ronald Jenner the paleontology newsletter (57)


for more details as to the many problems with Meyer's arguments see Meyer's Hopeless Monster.

Meyer may claim that 'a few scientists' have a particular viewpoint of the Cambrian explosion but other than a foundation in creationist rethoric, his viewpoints have limited scientific relevance (see for instance a review of the Cambrian by Christian scientists Keith B Miller [1>). Certainly the suggestion that such ideas deserve to be discussed in a highschool curriculum does a disservice to both science education as well as science itself.

What is worse is that Meyer artfully conflates two issues, namely the Cambrian explosion and the issue of a single common ancestor. First of all let it be clear that Darwinian theory nor Neo-Darwinian theory requires a single common ancestor. Anyone familiar with Darwin's writings would be aware of his position on these issues.
The evidence of common descent however is extremely solid as is described in full detail in Douglas Theobald's 29+ Evidences for Macroevolution The Scientific Case for Common Descent.



Some relevant resources




  1. Icons of ID: Carl Woese the final word? by Pim van Meurs
  2. The Precambrian to Cambrian Fossil Record and Transitional Forms by Keith B. Miller editor of Perspectives on an evolving creation

    There is much confusion in the popularized literature about the evidence for macroevolutionary change in the fossil record. Unfortunately, the discussion of evolution within the Christian community has been greatly influenced by inaccurate presentations of the fossil data and of the methods of classification. Widely read critiques of evolution, such as Evolution: A Theory in Crisis by Denton,1 and Darwin on Trial by Johnson,2 contain serious misrepresentations of the available fossil evidence for macroevolutionary transitions and of the science of evolutionary paleontology. In "On the Origin of Stasis by Means of Natural Processes," Battson similarly does not accurately communicate the rapidly growing body of evidence relevant to the Precambrian/Cambrian transition.

    ...

    The above discussion shows that the presentation of the Precambrian to Cambrian fossil record given by Battson does not reflect our present understanding of the history of life.32 Many metazoan groups appeared before the Cambrian, including representatives of several living phyla. Furthermore, the many small scale, plate, and spine-bearing organisms of the earliest Cambrian, while sharing characteristics with several living phyla, are also similar enough to each other to be classified by some workers into a single phylum.33 Even when the metazoan fossil record for the entire Cambrian is considered, the morphological disparity cannot be equated with that of living organisms, unless the subsequent appearance of all vertebrate and insect life be ignored. In addition, many living phyla, including most worm phyla, are unknown from the fossil record until well into the Phanerozoic.34 Thus, to claim the near simultaneous appearance of virtually all living phlya in the Cambrian is not an objective statement of the fossil evidence but a highly speculative, and I believe unsupported, interpretation of it.


  3. Taxonomy, Transitional Forms, and the Fossil Record Keith B Miller



  4. The literature speaks of "horizontal" change, which is acceptable because it is within the "kind." Although microevolution can explain horizontal change, evolution taking place "within a kind" is limited because genetic variation is limited: It is not possible to derive one kind from another. "Basic body plans," as creationists call them, are distinct from one another, and thus "vertical" changes between kinds cannot occur (Ramm 1955). In antievolution literature, vertical change equates with macroevolution, or evolution above the species level. The basic body plans of major phyla which appear in the so-called Cambrian explosion are seen by most Old Earth Creationists as evidence of Special Creation.
    Antievolutionism and Creationism in the United States, NCSE Resource





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