Intelligent Design

Darwin’s Dilemma Remains Unresolved: What Lee’s Paper Didn’t Discuss

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There has been much hullabaloo lately regarding a new paper published by a team of researchers, led by Associate Professor Michael Lee of the University of Adelaide, claiming that the abrupt appearance of dozens of animal groups in the early Cambrian period is no great mystery: rates of both morphological and genetic evolution were five times faster than today, that’s all. According to the paper, these rates “are still consistent with evolution by natural selection…, potentially resolving ‘Darwin’s dilemma.'” Are they right?

The authors of the paper, Michael Lee, Julien Soubrier and Gregory Edgecombe, attempted to measure the rate of evolution at two levels: the phenotypic level (which mostly relates to changes in an organism’s form and structure) and the molecular level (which relates to genetic changes in organisms). I was curious to see how the authors of the paper had actually measured the rate of phenotypic and molecular evolution during the Cambrian explosion. Here’s what I found in the paper:

Arthropods are the exemplar group for investigating questions about such macroevolutionary rates and patterns. They are the most abundant and diverse phylum in the early Paleozoic, have very complex preserved morphologies, and occupied extensive morphospace by the middle Cambrian [1,19,20]….

We here simultaneously infer rates of phenotypic and genomic change in arthropods during the Cambrian explosion and subsequent Phanerozoic, using a novel approach that exploits (1) the extensive phenotypic and genomic data available for living arthropods, (2) the calibration information available from the rich arthropod fossil record, and (3) adapting molecular clock methods for use on both genetic and morphological data…

Molecular and … phenotypic rates of evolution are expressed in % divergence per million years…

We here analyze an extensive data set of arthropods, consisting of 395 phenotypic characters [16] and 62 protein-coding genes [17,29], with 20 calibration points taken from the fossil record (Table S1)…

The phenotypic (largely “morphological”) data set consists of 395 characters (SI_13), scored for 53 panarthropod terminal taxa (Data file D1)… The character list is expanded and modified from Rota-Stabelli et al… The phenotypic data set for arthropods (Rota-Stabelli et al. 2011) was expanded to include 395 characters encompassing hard and soft tissues, internal and external anatomy, ultrastructure, embryology and gene expression patterns (SI_2, SI_13). There was a systematic attempt to sample character changes at all levels of arthropod phylogeny, attempting to catalogue derived characters (synapomorphies) uniting every pair or clade of sampled taxa, not only those changing on deep (Cambrian) branches…

The molecular data set consists of 62 protein coding genes sequenced for the 53 panarthropod terminals in the phenotypic data set (Regier et al. 2010) with an updated alignment (Regier and Zwick 2011). Fast-evolving data partitions dominated by synonymous sites were excluded, i.e. third codons, and first codons coding for leucine and arginine in any of the 53 taxa employed here (using LeuArg1: Hussey et al. 2010). The appropriateness of excluding or “degenerating” fast sites has been demonstrated empirically (Regier and Zwick 2011)…

Thus, in all calculations for average rates (e.g., Cambrian explosion, later Phanerozic), only ingroup branches are used in for molecular data, and only ingroup, internal branches for phenotypic data.

I’d like to make two very general observations here. First, measuring rates of change in existing traits is not the same thing as measuring the rate at which new traits appear.

Second, the rapid appearance of new body traits that occurred during the Cambrian explosion could never have taken place without a host of underlying changes at the genetic level. It is these changes that we need to explain. How do we explain, for instance, the sudden increase in the number of new cell types that occurred during the early Cambrian period? Lee et al. do not even discuss this question in their paper: a search on the phrase “cell type” turns up empty.

The impression I get is that Darwinists attempting to “debunk” the Cambrian explosion (or at least, cut it down to a manageable size) simply fail to grasp the fundamental issues raised by Dr. Stephen Meyer in his book, Darwin’s Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design (HarperOne, 2013).

But Meyer is not alone. In a recent post over at Evolution News and Views, Casey Luskin drew readers’ attention to a new book by paleobtologists Douglas Erwin and James Valentine, entitled, The Cambrian Explosion: The Construction of Animal Biodiversity (Roberts and Company, 2013). The authors, who are recognized authorities in their field, are no friends of Intelligent Design, but they firmly reject the standard neo-Darwinian explanations that have been put forward for the Cambrian explosion. In particular, they take issue with the claim that macroevolution is nothing more than an extrapolation of microevolution. A few excerpts from the introduction of their book will suffice to convey the tenor of their thought:

Today, some two dozen major eukaryotic groups have bodies composed of more than one cell, but few have progressed beyond the stage of an association of essentially identical cell types (Buss 1987; Knoll 2011). Eukaryotes include protistan colonies and various algae that have many cells, but there is no evidence that any of these groups has ever achieved the developmental control required to produce more complex morphologic patterns. Multicellular algae and fungi have only a few cell types, whereas other eukaryotic lineages are multicellular but exhibit none of the hierarchical structure of differentiation seen in plants and animals. At least eight different groups of these multicellular eukaryotes arose well before animals finally evolved sometime more than 750 million years ago (Ma). Complex multicellularity involves a hierarchical structure of differentiated cell types, tissues, organs, and the regionally differentiated structures found in animals and vascular land plants…

Multicellularity is a generative evolutionary innovation in the sense that it provides the basis for two additional important evolutionary steps: greater body size and increased division of labor among differentiated body parts. Greater size quite literally changes the nature of the world experienced by organisms… Body size is a multiplier of inertia, and most multicellular organisms are large enough that they cross the boundary into a world where inertial forces become important. At such larger sizes, most organisms evolved new ways of locomotion and feeding, facilitated by the specialization of cells, tissues, organs, and differentiated body parts. Such division of labor is evident even in sponges, the earliest metazoan group, but becomes far more pronounced in more complex animals…

Some 120 million to 170 million years after the origin of sponges, the scrappy fossil record improved with a bang, geologically speaking. Following a prelude of a diverse suite of enigmatic, soft-bodied organisms beginning about 579 Ma, a great variety and abundance of animal fossils appear in deposits dating from a geologically brief interval between about 530 to 520 Ma, early in the Cambrian period…

The subtitle of this book, The Construction of Animal Biodiversity, captures a second theme: the importance of building the networks that mediate the interactions… Increased genetic and developmental interactions were also critical to the formation of new animal body plans. By the time a branch of advanced sponges gave rise to more complex animals, their genomes comprised genes whose products could interact with regulatory elements in a coordinated network. Network interactions were critical to the spatial and temporal patterning of gene expression, to the formation of new cell types, and to the generation of a hierarchical morphology of tissues and organs. The evolving lineages could begin to adapt to different regions within the rich mosaic of conditions they encountered across the environmental landscape, diverging and specializing to diversify into an array of body forms.

Increased genetic and developmental interactions were also critical to the formation of new animal body plans. By the time a branch of advanced sponges gave rise to more complex animals, their genomes comprised genes whose products could interact with regulatory elements in a coordinated network. Network interactions were critical to the spatial and temporal patterning of gene expression, to the formation of new cell types, and to the generation of a hierarchical morphology of tissues and organs. The evolving lineages could begin to adapt to different regions within the rich mosaic of conditions they encountered across the environmental landscape, diverging and specializing to diversify into an array of body forms.

The nature of appropriate explanations is particularly evident in the final theme of the book: the implications that the Cambrian explosion has for understanding evolution and, in particular, for the dichotomy between microevolution and macroevolution. If our theoretical notions do not explain the fossil patterns or are contradicted by them, the theory is either incorrect or is applicable only to special cases… One important concern has been whether the microevolutionary patterns commonly studied in modern organisms by evolutionary biologists are sufficient to understand and explain the events of the Cambrian or whether evolutionary theory needs to be expanded to include a more diverse set of macroevolutionary processes. We strongly hold to the latter position.

Microevolutionary change often produces new species when different populations of a species are isolated genetically, or nearly so, such that each pursues a separate pathway of genetic change and they become distinct species; in animals, it usually means that they can no longer exchange genes. Macroevolution, by contrast, involves the study of what happens in evolution beyond the mechanisms of the formation of species. Some species, for example, are founders of major clades that encompass millions of species that occupy a wide range of ecological occupations, whereas other species are merely found in minor branches of life’s tree with rather similar ecologies or simply become extinct without issue (other patterns are not uncommon). Each of the species with those very different evolutionary outcomes arose through microevolutionary processes, yet there is obviously more to be said about their evolution, which forms the topic of macroevolution.

Reading through the introduction, it is readily apparent that Erwin and Valentine have thought long and hard about the issues relating to the Cambrian explosion, and that they truly appreciate the magnitude of the problem of explaining this seismic event in the history of life. By contrast, the new study by Lee et al. fails to grapple with the deeper issues: its aim is merely to defend Darwinism, and it “succeeds” only by shrinking the problem by focusing on minutiae such as rates of change in genes and phenotypic characters. No wonder, then, that the study’s authors perceive no threat to Darwinian evolution in the Cambrian explosion.

I’ll let the last word go to biologist Richard Deem, whose online review of Dr. Stephen Meyer’s book, Darwin’s Doubt, is well worth reading:

Darwin’s Doubt contains a number of chapters dedicated to the question of how new information and new genes can arise, which might explain the mechanism behind the Cambrian explosion. The problem is not as simple as it might seem at first, since not only were new body plans developed, but dozens of new kinds of organs, tissues and cell types for all those body plans. Such massive innovations require the addition of thousands of new genes that are perfectly integrated with each other in order to produce an organism that functions. The Darwinian explanations for the origin of genetic information would be hard-pressed to explain how all those new designs appeared.

15 Replies to “Darwin’s Dilemma Remains Unresolved: What Lee’s Paper Didn’t Discuss

  1. 1
    Mung says:

    Arthropods are the exemplar group for investigating questions about such macroevolutionary rates and patterns.

    But aren’t all arthropods in the same phylum? If so, what can they really tell us about the origin of phyla?

  2. 2
    scordova says:

    One researcher at that same university, John Hartnett, clearly rejects the results of the evolutionary biologists.

    It is nice to know that University of Adelaide host conflicting views of origins.

  3. 3
    bornagain77 says:

    As to:

    By contrast, the new study by Lee et al. fails to grapple with the deeper issues: its aim is merely to defend Darwinism, and it “succeeds” only by shrinking the problem by focusing on minutiae such as rates of change in genes and phenotypic characters.

    If theories of science are confirmed by ignoring all the contrary evidence to your starting presuppositions in your theory, then this ‘proof’, for neo-Darwinism, should become the standard by which all others theories of science are compared. If, on the other hand, one demands that all the relevant evidence be explained by a theory of science, then then this ‘proof’ should forever be taught as the primary example of how science OUGHT NOT be done! For primary example, at the base of neo-Darwinism it is presupposed that random variations of genotypes can produce variations of phenotypes, but we have no evidence that this is a feasible mechanism by which to produce fundamentally new body plans:

    Response to John Wise – October 2010
    Excerpt: A technique called “saturation mutagenesis”1,2 has been used to produce every possible developmental mutation in fruit flies (Drosophila melanogaster),3,4,5 roundworms (Caenorhabditis elegans),6,7 and zebrafish (Danio rerio),8,9,10 and the same technique is now being applied to mice (Mus musculus).11,12 None of the evidence from these and numerous other studies of developmental mutations supports the neo-Darwinian dogma that DNA mutations can lead to new organs or body plans–because none of the observed developmental mutations benefit the organism.
    http://www.evolutionnews.org/2.....38811.html

    Scant search for the Maker
    Excerpt: But where is the experimental evidence? None exists in the literature claiming that one species has been shown to evolve into another. Bacteria, the simplest form of independent life, are ideal for this kind of study, with generation times of 20 to 30 minutes, and populations achieved after 18 hours. But throughout 150 years of the science of bacteriology, there is no evidence that one species of bacteria has changed into another, in spite of the fact that populations have been exposed to potent chemical and physical mutagens and that, uniquely, bacteria possess extrachromosomal, transmissible plasmids. Since there is no evidence for species changes between the simplest forms of unicellular life, it is not surprising that there is no evidence for evolution from prokaryotic to eukaryotic cells, let alone throughout the whole array of higher multicellular organisms. –
    Alan H. Linton – emeritus professor of bacteriology, University of Bristol.
    http://www.timeshighereducatio.....ode=159282

    Darwin or Design? – Paul Nelson at Saddleback Church – Nov. 2012 – ontogenetic depth (excellent update) – video
    Text from one of the Saddleback slides:
    1. Animal body plans are built in each generation by a stepwise process, from the fertilized egg to the many cells of the adult. The earliest stages in this process determine what follows.
    2. Thus, to change — that is, to evolve — any body plan, mutations expressed early in development must occur, be viable, and be stably transmitted to offspring.
    3. But such early-acting mutations of global effect are those least likely to be tolerated by the embryo.
    Losses of structures are the only exception to this otherwise universal generalization about animal development and evolution. Many species will tolerate phenotypic losses if their local (environmental) circumstances are favorable. Hence island or cave fauna often lose (for instance) wings or eyes.
    http://www.saddleback.com/mc/m/7ece8/

    The Fate of Darwinism: Evolution After the Modern Synthesis – David J. Depew and Bruce H. Weber – 2011
    Excerpt: We trace the history of the Modern Evolutionary Synthesis, and of genetic Darwinism generally, with a view to showing why, even in its current versions, it can no longer serve as a general framework for evolutionary theory. The main reason is empirical. Genetical Darwinism cannot accommodate the role of development (and of genes in development) in many evolutionary processes.,,,
    http://www.springerlink.com/co.....03g3t7002/

    With a Startling Candor, Oxford Scientist Admits a Gaping Hole in Evolutionary Theory – November 2011
    Excerpt: As of now, we have no good theory of how to read [genetic] networks, how to model them mathematically or how one network meshes with another; worse, we have no obvious experimental lines of investigation for studying these areas. There is a great deal for systems biology to do in order to produce a full explanation of how genotypes generate phenotypes,,,
    http://www.evolutionnews.org/2.....52821.html

    The next evolutionary synthesis: Jonathan BL Bard (2011)
    Excerpt: We now know that there are at least 50 possible functions that DNA sequences can fulfill [8], that the networks for traits require many proteins and that they allow for considerable redundancy [9]. The reality is that the evolutionary synthesis says nothing about any of this; for all its claim of being grounded in DNA and mutation, it is actually a theory based on phenotypic traits. This is not to say that the evolutionary synthesis is wrong, but that it is inadequate – it is really only half a theory!
    http://www.biosignaling.com/co.....X-9-30.pdf

    Not Junk After All—Conclusion – August 29, 2013
    Excerpt: Many scientists have pointed out that the relationship between the genome and the organism — the genotype-phenotype mapping — cannot be reduced to a genetic program encoded in DNA sequences. Atlan and Koppel wrote in 1990 that advances in artificial intelligence showed that cellular operations are not controlled by a linear sequence of instructions in DNA but by a “distributed multilayer network” [150]. According to Denton and his co-workers, protein folding appears to involve formal causes that transcend material mechanisms [151], and according to Sternberg this is even more evident at higher levels of the genotype-phenotype mapping [152].
    http://www.uncommondescent.com.....onclusion/

  4. 4
    bornagain77 says:

    The severity of the problem facing neo-Darwinists becomes clear if we consider what it would take for evolution just to find a single protein:

    Evolution Vs. Functional Proteins – climbing mount improbable – Axe, Meyer – video
    http://www.metacafe.com/watch/4018222/

    Yet even if neo-Darwinism were able to find fundamentally new functional proteins (which we have no proof of it being able to do currently), the mechanism of neo-Darwinism addresses the problem of generating new body plans from the wrong conceptual, i.e. ‘bottom up’, level:

    Stephen Meyer – Functional Proteins And Information For Body Plans – video
    http://www.metacafe.com/watch/4050681

    Dr. Stephen Meyer comments at the end of the preceding video,,,

    ‘Now one more problem as far as the generation of information. It turns out that you don’t only need information to build genes and proteins, it turns out to build Body-Plans you need higher levels of information; Higher order assembly instructions. DNA codes for the building of proteins, but proteins must be arranged into distinctive circuitry to form distinctive cell types. Cell types have to be arranged into tissues. Tissues have to be arranged into organs. Organs and tissues must be specifically arranged to generate whole new Body-Plans, distinctive arrangements of those body parts. We now know that DNA alone is not responsible for those higher orders of organization. DNA codes for proteins, but by itself it does not insure that proteins, cell types, tissues, organs, will all be arranged in the body. And what that means is that the Body-Plan morphogenesis, as it is called, depends upon information that is not encoded on DNA. Which means you can mutate DNA indefinitely. 80 million years, 100 million years, til the cows come home. It doesn’t matter, because in the best case you are just going to find a new protein some place out there in that vast combinatorial sequence space. You are not, by mutating DNA alone, going to generate higher order structures that are necessary to building a body plan. So what we can conclude from that is that the neo-Darwinian mechanism is grossly inadequate to explain the origin of information necessary to build new genes and proteins, and it is also grossly inadequate to explain the origination of novel biological form.’ –
    Stephen Meyer – (excerpt taken from Meyer/Sternberg vs. Shermer/Prothero debate – 2009)

    The following articles highlight the almost sheer disconnect between genotypes and phenotypes:

    Extreme Genome Repair – 2009
    Excerpt: If its naming had followed, rather than preceded, molecular analyses of its DNA, the extremophile bacterium Deinococcus radiodurans might have been called Lazarus. After shattering of its 3.2 Mb genome into 20–30 kb pieces by desiccation or a high dose of ionizing radiation, D. radiodurans miraculously reassembles its genome such that only 3 hr later fully reconstituted nonrearranged chromosomes are present, and the cells carry on, alive as normal.,,,
    http://www.ncbi.nlm.nih.gov/pm.....MC3319128/

    What Do Organisms Mean? Stephen L. Talbott – Winter 2011
    Excerpt: Harvard biologist Richard Lewontin once described how you can excise the developing limb bud from an amphibian embryo, shake the cells loose from each other, allow them to reaggregate into a random lump, and then replace the lump in the embryo. A normal leg develops. Somehow the form of the limb as a whole is the ruling factor, redefining the parts according to the larger pattern. Lewontin went on to remark: “Unlike a machine whose totality is created by the juxtaposition of bits and pieces with different functions and properties, the bits and pieces of a developing organism seem to come into existence as a consequence of their spatial position at critical moments in the embryo’s development. Such an object is less like a machine than it is like a language whose elements… take unique meaning from their context.[3]”,,,
    http://www.thenewatlantis.com/.....nisms-mean

    An Electric Face: A Rendering Worth a Thousand Falsifications – September 2011
    Excerpt: The video suggests that bioelectric signals presage the morphological development of the face. It also, in an instant, gives a peak at the phenomenal processes at work in biology. As the lead researcher said, “It’s a jaw dropper.”
    https://www.youtube.com/watch?v=wi1Qn306IUU
    http://darwins-god.blogspot.co.....usand.html

    HOW BIOLOGISTS LOST SIGHT OF THE MEANING OF LIFE — AND ARE NOW STARING IT IN THE FACE – Stephen L. Talbott – May 2012
    Excerpt: The same sort of question can be asked of cells, for example in the growing embryo, where literal streams of cells are flowing to their appointed places, differentiating themselves into different types as they go, and adjusting themselves to all sorts of unpredictable perturbations — even to the degree of responding appropriately when a lab technician excises a clump of them from one location in a young embryo and puts them in another, where they may proceed to adapt themselves in an entirely different and proper way to the new environment. It is hard to quibble with the immediate impression that form (which is more idea-like than thing-like) is primary, and the material particulars subsidiary.
    Two systems biologists, one from the Max Delbrück Center for Molecular Medicine in Germany and one from Harvard Medical School, frame one part of the problem this way:
    “The human body is formed by trillions of individual cells. These cells work together with remarkable precision, first forming an adult organism out of a single fertilized egg, and then keeping the organism alive and functional for decades. To achieve this precision, one would assume that each individual cell reacts in a reliable, reproducible way to a given input, faithfully executing the required task. However, a growing number of studies investigating cellular processes on the level of single cells revealed large heterogeneity even among genetically identical cells of the same cell type. (Loewer and Lahav 2011)”,,,
    http://www.netfuture.org/2012/May1012_184.html#2

    Thus, to repeat,,, If theories of science are confirmed by ignoring all the contrary evidence to your starting presuppositions in your theory, then this ‘proof’ (highlight in the OP), for neo-Darwinism, should become the standard by which all others theories of science are compared. If, on the other hand, one demands that all the relevant evidence be explained by a theory of science, then then this ‘proof’ should forever be taught as the primary example of how science OUGHT NOT be done!

    Verse and Music:

    1 Thessalonians 5:21
    But examine everything carefully; hold fast to that which is good;

    Gungor “Beautiful Things” – video
    http://www.youtube.com/watch?v=oyPBtExE4W0

  5. 5
    ddwer says:

    Hi there,

    I’m new to the forum. Nice that this site exists.
    Could someone summarize the evidences that are against the evolution theory? Or summarize the flaws of the theory…

    Hope someone can help me.

  6. 6
    vjtorley says:

    Hi bornagain77,

    Thanks very much for the links – especially the video links to Dr. Stephen Meyer’s talks, and the links to Stephen Talbott’s articles. I greatly appreciate your indefatigable research.

  7. 7
    vjtorley says:

    Hi Sal,

    Thanks for the update on John Hartnett. Last time I heard, he was still with the University of Western Australia. Here are some links for interested readers:

    http://creation.com/exploding-the-big-bang
    http://creation.com/new-creation-cosmology
    http://creation.com/dark-matte.....-cosmology
    http://www.4thdayalliance.com/.....-hartnett/
    http://www.4thdayalliance.com/.....-hartnett/

    I’m not a young earth creationist myself, but I have a lot of respect for Dr. Hartnett. He is trying to develop models which make testable predictions. Good for him.

    Hi Mung,

    Good point about arthropods. The origin of animal phyla is a major unsolved mystery of paleontology, and the narrow scope of Lee et al.’s study prevents them from addressing it.

  8. 8
    johnp says:

    ddwer-

    Refer to bornagain77’s posts above for links to evidences against the materialistic “mud to man” evolutionary theory.

    Hope your search goes well!

  9. 9
  10. 10
    ddwer says:

    Thanks for the links guys, going to check them.
    Can someone also in laymans terms summarize the evidences against evolution for me? I’m trying to grasp the pro’s and cons but it’s rather difficult if your no scientist :-). And why are evolutionist debunking the evidences against evolution you guys think?

    Hope to hear from you!

  11. 11
    Mung says:

    Shouldn’t the title be Darwin’s Dilemna?

    But to answer my own self’s comment @1:

    It is tempting to correlate homeotic changes with the diversification of segmentation patters in arthropods, for example, the group that provides the most diverse and disparate Cambrian sample and has also received substantial attention from developmental biologists today.

    Wonderful strife: systematics, stem groups, and the phylogeneetic signal of the Cambrian radiation

  12. 12
    Phinehas says:

    ddwer:

    Can someone also in laymans terms summarize the evidences against evolution for me?

    It depends on what you mean by “evolution.” All of the posters here believe that evolution exists in nature, but some of us believe there are limits to what it can accomplish, even over large time periods. Michael Behe’s The Edge of Evolution lays out the evidence for these limits. In addition, we note the lack of evidence that evolution can achieve results beyond these limits.

    ID isn’t just about evidence concerning the limits of evolution, however. There are certain things that, based on the finite resources of the universe, are extremely unlikely to be produced by chance and necessity alone. This post is an example of such a thing. Based on overwhelming experience, such things are consistently and reliably found to be the work of an intelligent agent. ID believes that there are certain characteristics that these things share in common and that these same characteristics can be seen in the systems and machinery of living organisms.

  13. 13
    vjtorley says:

    Hi Mung,

    Thanks for your comments. I did actually respond to your earlier comment (#1) above – see #7 above, which was actually two comments rolled into one.

    By the way, “dilemma” is the correct spelling. See here and here. Apparently many people were incorrectly taught the spelling of the word, at school.

    Re homeotic genes, here are a couple of quotes that may interest you:

    “There is also continued interest in the role of genomic change, especially with respect to the homeotic genes. Although they are clearly of central importance in the definition of bodyplan architecture, there is a risk of losing the overall evolutionary context. It is evident that at least some components of a given bodyplan are assembled by virtue of a genetic “toolbox.” This, in turn, has provoked extensive discussions on definitions of homology, but perhaps deflects the interesting question of how such toolboxes are recruited. This is no trivial point because there is increasing evidence for extensive co-option and redeployment of genes. Not only that, but there are intriguing mismatches between genomic architecture and bodyplan complexity. To complicate matters further, a substantial proportion of the metazoan genome was probably available well before the Cambrian explosion. Genes make bodies and bodyplans require a corresponding genetic architecture, but we are still far from understanding either their interconnections or evolution.”
    – Simon Conway Morris, “The Cambrian ‘explosion’: Slow-fuse or megatonnage?“, PNAS vol. 97 no. 9, 2000, pp. 4426–4429.

    and

    As homeotic genes turn out to be more and more universal, the control they exercise in development turns out to be less and less specific…. [T]he universality of homeotic genes is supposed to be due to their presence in a common ancestor, but the preponderance of the evidence suggests that the common ancestor lacked the features that those homeotic genes now supposedly control. From a Darwinian perspective this is a serious problem. According to neo-Darwinism complex gene sequences gradually evolve by conferring selective advantages on the organisms that possess them. But gene sequences confer selective advantages only if they program the development of useful adaptations. If a primitive animal possessed homeotic genes but lacked all of the adaptations now associated with them, then those genes must have originated prior to these adaptations. How then, did homeotic genes evolve?
    – Jonathan Wells, “Unseating Naturalism: Recent Insights from Developmental Biology“, in W. A. Dembski, ed., Mere Creation: Science, Faith & Intelligent Design. Downers Grove: IVP, 1998, pp. 51-70, see esp. pp. 53-58. Cited by Casey Luskin here.

  14. 14
    vjtorley says:

    Hi ddwer,

    Professor Jerry Coyne’s highly accessible Why Evolution Is True is available online. Here’s a critical review by Dr. Jonathan Wells: http://www.discovery.org/a/10661

  15. 15
    Mung says:

    hi vjt, I did see your response, but I feared I had perhaps misled you (and others) in my #1. Never one to let a sleeping lie be a dog…

    As I read more on the Arthropods one wonders how they are even classified as single phylum (HT: Stephen Meyer for explaining the correct terminology in his Darwin’s Doubt.)

    Even my reading last night revealed more of the disparity even among arthropods! So perhaps there is something to be learned from studying the pattern they present.

    One of the challenges of disparity studies, however, is that almost all the quantitative techniques are best applied within a common body plan, where homologous characters are present.

    As we discussed for the arthropods, a single sample of Cambrian arthropod disparity from the Burgess Shale occupied a larger volume of morphospace than a representative sample of living arthropods. … There have been numerous quantitative studies of morphologic disparity since the early 1990s, and many (but not all) have identified a pattern of great, even maximal disparity early in clade histories.

    Quotes from The Cambrian Explosion: The Construction of Animal Biodiversity

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