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Re: ... 2. PE 10.2.1. "Fossil Record ...Sudden appearance ... Cambrian explosion"

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  • Stephen E. Jones
    Group I have today handed in my last assignment (on the Cambrian explosion)! I now have a *lot* of `swatting for my last three exams due within the next 15
    Message 1 of 5 , Nov 1, 2004
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      Group

      I have today handed in my last assignment (on the Cambrian explosion)! I
      now have a *lot* of `swatting' for my last three exams due within the next
      15 days. So I will probably just do quick posts in the interim (i.e. I probably
      won't add anything to my "Problems of Evolution" book outline
      (http://members.iinet.net.au/~sejones/pe00cont.html)", as that takes too
      much time.

      On Sat, 30 Oct 2004 17:47:25 -0700, Cliff Lundberg wrote:

      [...]

      >SJ>Having nearly finished my assignment on the Cambrian explosion,
      >>I am now fairly clear on how it happened. Basically it was a miracle
      >>of timing in which *many* environmental and `pre-adapted' biological
      factors
      >>came together, at the *right* time and place. It certainly had little
      >>to do with Darwinism! But I don't have time to flesh this out now, but
      will
      >>do so later after my final exam on 15 November(!).

      CL>I look forward to that. I will probably argue that the pre-eminent
      >pre-adapting factor was the multiplication of bodies into trains
      >of segments, masses of unspecialized articulated parts which were
      >free to be rapidly adapted to specialized uses through loss and
      >distortion, forming arthropods and vertebrates without the problematic
      need
      >of adding new parts in fortuitous positions.

      Cliff is free to "argue" what he likes, but as I have said many time before,
      I am not interested in debating Cliff's personal "loss and distortion"
      theory, unless he documents his claims from the scientific literature.

      To help Cliff get started, here is my list of references from my assignment
      on the Cambrian explosion that he might want to get and read (as I did):

      --------------------------------------------------------------------------
      [...]

      References

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      Babcock, L.E. (2001). The Chengjiang Biota: Record of the Early
      Cambrian Diversification of Life and Clues to Exceptional Preservation of
      Fossils, GSA Today, 11(2), 4-9.

      Bengtson, S. (1998). Animal embryos in deep time. Nature, 391, 529-530.

      Bengtson, S., & Zhao, Y. (1997). Fossilized Metazoan Embryos from the
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      Benton, M.J., & Ayala, F.J. (2003). Dating the Tree of Life. Science,
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      Bowring, S.A., Grotzinger, J.P., Isachsen, C.E., Knoll, A.H., Pelechaty,
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      Budd, G.E. (2004). Palaeontology: lost children of the Cambrian. Nature,
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      Carroll, R.L. (1997). Patterns and Processes of Vertebrate Evolution.
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      Carroll, R.L. (2000). Towards a new evolutionary synthesis. Trends in
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      Chen, J.-Y., Bottjer, D.J., Oliveri, P., Dornbos, S.Q., Gao, F., Ruffins, S.,
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      Chen, J.Y., Huang, D.Y., & Li, C.W. (1999). An early Cambrian craniate-
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      Chen, J.-Y., Huang, D.-Y., Peng, Q.-Q., Chi, H.-M., Wang, X.-Q., & Feng
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      Conway Morris S. (1998). The Crucible of Creation: The Burgess Shale
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      Dong, Xi-P., Donoghue, P.C.J., Cheng, H., & Liu, J.-B. (2004). Fossil
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      Donnadieu, Y., Godd�ris, Y., Ramstein, G., N�d�lec, A., Meert, J. (2004).
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      Erwin, D.H. & Davidson, E.H. (2002). The last common bilaterian
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      Eyles, N., & Januszczak, N. (2004). �Zipper-rift�: a tectonic model for
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      Earth-Science Reviews, 65(1-2), 1-73.

      Fortey, R. (2001). The Cambrian explosion exploded? Science, 293, 438.

      Giribet, G. (2002). Current advances in the phylogenetic reconstruction of
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      Gould, S.J. (1978). Ever Since Darwin: Reflections in Natural History.
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      Gould, S.J. (1980). The Panda's Thumb: More Reflections in Natural
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      Gould, S.J. (1989). Wonderful Life: The Burgess Shale and the Nature of
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      Gould, S.J. (1994a). The Evolution of Life on the Earth. Scientific
      American, 271(4), 63-69.

      Gould, S.J. (1994b). In the mind of the beholder, Natural History, 103(2),
      14, 16-23.

      Gould, S.J. (1998). On embryos and ancestors. Natural History, 107(6), 20-
      22, 58-65.

      Gould, S.J. (2002). The Structure of Evolutionary Theory. Cambridge, MA:
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      Hecht, J. (1995). Evolution's big bang explained, New Scientist, 148, 2
      December, p.23.

      Hedges, S.B., Blair, J.E., Venturi, M.L., Shoe, J.L. (2004). A molecular
      timescale of eukaryote evolution and the rise of complex multicellular life.
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      Hickman, C.P., Jr., Roberts, L.S., & Larson, A. (2000). Animal Diversity.
      Boston, MA: McGraw-Hill, Second Edition.

      Hoffman, P.F., Kaufman, A.J., Halverson, G.P., & Schrag, D.P. (1998). A
      Neoproterozoic Snowball Earth. Science; 281, 1342-1346.

      Hoffman, P.F. & Schrag, D.P. (1999). The Snowball Earth.
      http://www-eps.harvard.edu/people/faculty/hoffman/Snowball-fig12.jpg

      Holmes, R. (1997). When we were worms. New Scientist, 156, 30.

      Hyde, W.T., Crowley, T.J., Baum, S.K., Peltier, W.R. (2000).
      Neoproterozoic 'snowball Earth' simulations with a coupled climate/ice-
      sheet model. Nature, 405, 425-429.

      Kerr, R.A. (1993). Evolution's Big Bang Gets Even More Explosive.
      Science, 261, 1274-1275.

      Kerr, R.A. (1998a). Pushing Back the Origins of Animals. Science, 279,
      803-804.

      Kerr, R.A. (1998b).Tracks of Billion-Year-Old Animals? Science, 282, 19-
      21.

      Kerr, RA. (2002). A trigger for the Cambrian explosion? Science, 298,
      1547.

      Kirschvink, J.L., & Raub, T.D. (2003). A methane fuse for the Cambrian
      explosion: carbon cycles and true polar wander. Comptes Rendus
      Geoscience, 335(1), 65-78.

      Knoll, A.H. (2000). Learning to tell Neoproterozoic time. Precambrian
      Research, 100(1-3), 3-20.

      Knoll, A.H. (2003). Vestiges of a beginning? Paleontological and
      geochemical constraints on early animal evolution. Annales de
      Paleontologie, 89(4), 205-221.

      Knoll, A.H., & Carroll, S.B. (1999). Early Animal Evolution: Emerging
      Views from Comparative Biology and Geology. Science, 284, 2129-2137.

      Knoll, A.H., Walter, M.R. Narbonne, G.M., Christie-Blick, N. (2004). A
      New Period for the Geologic Time Scale. Science, 305, 621-622.

      Knight, J. (1997). Gutsy ancestors. New Scientist, 156, 13 December.

      Knight, J. (1998). An eye for colour. New Scientist, 158, 13 June.

      Levinton, J.S. (1992). The Big Bang of Animal Evolution. Scientific
      American, 267(5), 52-59.

      Li, C.-W., Chen, J.-Y., & Hua, T.-E. (1998). Precambrian Sponges with
      Cellular Structures. Science, 279, 879-882.

      Margulis, L., Schwartz, K.V., & Dolan, M. (1994), The Illustrated Five
      Kingdoms: A Guide to the Diversity of Life on Earth. New York, NY:
      HarperCollins College Publishers.

      Mojzsis, S.J., Arrhenius, G., McKeegan, K.D., Harrison, T.M., Nutman,
      A.P. & Friend, C.R.L. (1996). Evidence for life on Earth before 3,800
      million years ago. Nature, 384, 55-59.

      Orr, P.J., Briggs, D.E.G., & Kearns, S.L. (1998). Cambrian Burgess Shale
      Animals Replicated in Clay Minerals. Science, 281, 1173-1175.

      Raff, R.A. (1999). Creating the animal planet: The Crucible of Creation-
      The Burgess Shale and the Rise of Animals by Simon Conway Morris, and
      The Garden of Ediacara-Discovering the First Complex of Life by Mark
      A.S. McMenamin. Trends in Ecology & Evolution. 14(1), 39.

      Rai, V. & Gautam, R. (1999). Evaluating Evidence of Ancient Animals.
      Science, 284, 1235.

      Runnegar, B. (2000). Loophole for snowball Earth. Nature, 405, 403-404.

      Schopf, J.W. (1993). Microfossils of the Early Archean Apex chert: new
      evidence of the antiquity of life. Science, 260, 640-646.

      Seilacher, A., Bose, P.K., Pfl�ger, F. (1998). Triploblastic Animals More
      Than 1 Billion Years Ago: Trace Fossil Evidence from India. Science,
      282(5386), 80-83.

      Shu, D.G., Luo, H.L., Conway Morris, S., Zhang, X.L., Hu, S.X., Chen, L.,
      Han, J., Zhu, M., Li, Y., & Chen, L.Z. (1999). Lower Cambrian vertebrates
      from south China. Nature, 402, 42-46.

      Siveter, D.J., Williams, M., & Waloszek, D. (2001). A Phosphatocopid
      Crustacean with Appendages from the Lower Cambrian. Science, 293, 479-
      481.

      Sprigg, R.C. (1947). Early Cambrian (?) Jellyfishes from the Flinders
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      Tice, M.M. & Lowe, D.R. (2004). Photosynthetic microbial mats in the
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      The William Younger Centre. (2000). Our Dynamic Earth, Edinburgh, UK.
      http://www.dynamicearth.co.uk/education/images/burgess_shale.jpg

      University of California Museum of Paleontology (n.d.). Vendian Animals:
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      http://www.ucmp.berkeley.edu/vendian/dickinsonia.html.

      Wray, G.A., Levinton, J.S. & Shapiro, L.H. (1996). Molecular Evidence for
      Deep Precambrian Divergences Among Metazoan Phyla. Science, 274,
      568-573.

      Xiao, S., Zhang, Y., & Knoll, A.H. (1998). Three-dimensional preservation
      of algae and animal embryos in a Neoproterozoic phosphorite. Nature, 391,
      553-558.

      Zhang, X.-G., & Pratt, B.R. (1994). Middle Cambrian arthropod embryos
      with blastomeres. Science, 266, 637-38.
      --------------------------------------------------------------------------

      I am *not* saying that members have to do this level of research in order to
      post to CED. Members (including Cliff) can post to CED whatever they
      like on any C/E/D topic. But as for *me*, my focus is on engaging with and
      critiquing the *mainstream* scientific theory of evolution.

      From my reading, this is the basic picture of the Cambrian explosion
      (which I see no reason to dispute):

      ~1000-600 Ma: Three `snowball Earth' ice-house the greenhouse events,
      caused by the Rodinia supercontinent around the South Pole, forming and
      breaking up, with disruptions to carbon-silicate cycle. Earth's *average
      global* temperature swung from -50�C to -50�C. Each event was a global
      catastrophe equivalent to an asteroid impact. The oceans froze solid all the
      way down to the seabed, except for a narrow belt of open water around the
      Equator(which if it were not for yet another set of fine-tuned `co-
      incidences' the ocean would have frozen solid and eukaryotic life would
      have been extinguished). Each time eukaryotic life was nearly snuffed out
      by ~5 km ice sheets that reached nearly to the Equator . After each of the
      three icehouse-greenhouse event, the Earth as repopulated by the surviving
      eukaryotic lineages.

      ~700 Ma: a microscopic planktonic larvae had a set of no less than *10*
      homeotic (hox) genes that could then build a worm-like body with
      triploblastic (three primary) tissue layers to build a complex, mobile body
      with an anterior-posterior (head-tail) orientation, a bilaterally symmetrical
      body plan, a mouth-anus gut, paired appendages, paired sensory receptors
      on its head end, etc.

      This bilaterian common ancestor lineage also had `set aside' cells which, in
      conjunction with hox genes, would allowed a two-stage (larva-adult)
      development and could migrate to other parts of the body (as in many
      invertebrates today ) to build many different body-plans.

      ~650 Ma: this totipotent Bilaterian common ancestor lineage of *all* the
      triploblastic Metazoa, then diverged into three superclades, the
      deuterostomes, from which came echinoderms (e.g. starfish, sea squirts,
      etc) and chordates (e.g. amphioxus and vertebrates, etc); and two
      superclades of protostomes, the ecdysozoans, or moulting phyla
      (arthropods, nematodes, etc), and lophotrochozoans (annelids, molluscs,
      flatworms, etc). Interesting the pax-6 gene that alone can build true eyes is
      in four phyla (chordates, arthropods, annelids and molluscs), which are in
      all three superclades, so the Bilaterian common ancestor must have been
      `pre-adapted' with that too!

      ~600 Ma: The third and final `snowball Earth' event had ended and the first
      (albeit microscopic) bilaterally symmetrical, triploblastic metazoan animals
      had appeared (since their phosphatised fossil embryos have now been
      found in China).

      ~550 Ma. The first undisputed worm burrows and tracks are found in a
      number of places, indicating an adult bilaterian body with a hydrostatic
      skeleton and locomotion.

      ~533 Ma. The main pulse of the Cambrian explosion had began and then by
      525 Ma (8-5 million years later) it ended, with all but a few of the ~35
      modern animal phyla (basic body plans) having appeared.

      While this does not fit YEC or Old-Earth/Fiat Creation , it does not come
      even *close* to fitting Darwinian RM&NS either. It does however fit my
      Old-Earth/Mediate Creation model quite nicely (the proof of that is that I
      have no problem accepting the evidence).

      Oxford zoologist Andrew Parker's book on the Cambrian explosion, "In the
      Blink of an Eye" came today. In dipping into it briefly, the following quote
      debunking the Chinese `feathered dinosaurs' caught my eye (pun
      unintended!).

      Steve

      [...]

      PS. I had forgotten about this (see tagline). Since birds have a unique type
      of lungs, if this `feathered' dinosaur, Sinosauropteryx, did not have bird-type
      lungs, then it cannot have been ancestral to birds. In that case its `feathers'
      cannot be bird feathers. But in that case, there is no reason for thinking that
      *any* of the `feathered' dinosaurs have true feathers. Which would mean
      that yet *another* `icon' of evolution has gone down the gurgler!


      --------------------------------------------------------------------------
      "The precise relationship between dinosaurs and birds is a highly
      controversial issue. Signs of early feathers on a newly discovered Chinese
      dinosaur have been rejected by many, who prefer the interpretation that the
      downy outlines of the fossils are simply fibres from the skin that can fray
      when reptile skin surface is damaged. Ironically the specimen in question, a
      120-million-year-old Sinosauropteryx, a theropod, has been brought to
      virtual life only to deliver a blow to its excavators, who sit within the
      'dinosaurs-are-birds' camp. The fine silt from an ancient lake had preserved
      the soft structures of Sinosauropteryx, including a clear silhouette of the
      lungs. John Ruben, a respiratory expert from Oregon State University, took
      one look at the 'lungs' and knew what he was dealing with. He had seen this
      lung arrangement before - in crocodiles. Immediately he constructed his
      virtual, living dinosaur, with the same compartmentalisation of lungs, liver
      and intestines that one would find in a crocodile, and not in a bird. This
      virtual dinosaur was incapable of the high rates of gas exchange needed for
      warm- bloodedness. So it contained cold blood, like the crocodile. Also, its
      bellows-like lungs could not have conceivably evolved into the high-
      performance lungs of modern birds. But still this evidence, that birds were
      not descendants of dinosaurs, is far from conclusive. As new fossils are
      unearthed and analysed with the lives of modern animals in mind, the
      building of a virtual dinosaur continues. (Parker A.R., "In the Blink of an
      Eye," Perseus: Cambridge MA, 2003, pp.73-74)
      Stephen E. Jones http://members.iinet.net.au/~sejones
      Moderator: http://groups.yahoo.com/group/CreationEvolutionDesign
      --------------------------------------------------------------------------
    • Cliff Lundberg
      From: Stephen E. Jones ... time before, ... distortion ... literature. It s well known that since their Cambrian emergence, animal
      Message 2 of 5 , Nov 1, 2004
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        From: "Stephen E. Jones" <sejones@...>

        > Cliff is free to "argue" what he likes, but as I have said many
        time before,
        > I am not interested in debating Cliff's personal "loss and
        distortion"
        > theory, unless he documents his claims from the scientific
        literature.

        It's well known that since their Cambrian emergence, animal types
        have remained the basically the same, only changing in relatively
        superficial ways. The claim that these relatively small changes
        were matters of distortion (unlike the original creative process,
        in which wholly new parts came into existence) shouldn't be
        viewed as all that idiosyncratic.

        My article would be more impressive to some if it had it an
        lengthy bibliography--that's one thing I did learn in school.
        But it would be mere padding in this case. It's a matter of
        interpretation. New findings of particular fossils don't
        bring new insight at a more general level.

        > To help Cliff get started, here is my list of references from my
        assignment
        > on the Cambrian explosion that he might want to get and read (as
        I did):

        I spent the 80's enjoying such research. Since then I merely
        scan the literature, looking for (but not finding) any comment
        on mechanisms for rapid evolution, and on the validity of the
        pattern of reduction and specialization over time among the
        parts of segmented skeletons. These are the things that interest
        me. Of course it's interesting to see new animals discovered,
        and new statistics about groups of animals, and more refined
        chronology, and the narrowing of the time frame for the CE.
        But I don't see anything in the literature affecting my model
        one way or the other.

        Cliff
      • Stephen E. Jones
        Group Another quick study avoidance post! ... CL It s well known that since their Cambrian emergence, animal types ... There is a show-stopper for Cliff s
        Message 3 of 5 , Nov 2, 2004
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          Group

          Another quick study avoidance post!

          On Mon, 1 Nov 2004 23:41:34 -0800, Cliff Lundberg wrote:

          >SJ>Cliff is free to "argue" what he likes, but as I have said many
          >>time before, I am not interested in debating Cliff's personal "loss and
          >>distortion" theory, unless he documents his claims from the scientific
          >>literature.

          CL>It's well known that since their Cambrian emergence, animal types
          >have remained the basically the same, only changing in relatively
          >superficial ways. The claim that these relatively small changes
          >were matters of distortion (unlike the original creative process,
          >in which wholly new parts came into existence) shouldn't be
          >viewed as all that idiosyncratic.

          There is a show-stopper for Cliff's "reduction and distortion" theory
          (i.e. as a *general* theory-no one denies that there has been "reduction
          and distortion") in that all of a sudden, fossil worm trails and burrows
          show up in what was soft seafloor mud ~550 mya. Since the mud below was
          the same as the mud the trace fossils are found in, this is the strongest possible evidence that triploblastic complex worm-like adult animals came
          into existence ~550 mya (presumably descended from microscopic larval
          forms of which there are phosphatised fossil embryos ~600 mya). There
          are claimed worm faecal pellets ~600 mya, but this is less certain.

          I don't have a quote handy at the moment, but here is the relevant
          section out of my assignment:

          --------------------------------------------------------------------------
          [...]

          Trace fossil burrows (~1 Ga & ~550 Ma)
          Evidence of burrowing trace fossils ~1 Ga has been claimed (Seilacher,
          Bose & Pflüger, 1998). But this has been challenged as an inorganic
          pseudo-fossil (Kerr, 1998b; Rai & Gautam, 1999). However, undisputed
          trails and burrows have been found extending back to 550 Ma (Erwin &
          Davidson, 2002; Knoll & Carroll, 1999). Fossilised faecal pellets have also
          been found ~600 Ma (Knight, 1997). These trace fossils were evidently
          made by bilaterally symmetrical, worm-like animals with a mouth-anus
          digestive tract (Carroll, 2000). [...]
          --------------------------------------------------------------------------

          Cliff is of course free to ignore this evidence, but then he should not expect
          me (for starters) to take his "reduction and distortion" theory seriously.

          [...]

          Steve


          --------------------------------------------------------------------------
          "Biology is the study of complicated things that give the appearance
          of having been designed for a purpose." (Dawkins R., "The Blind
          Watchmaker," [1986], Penguin: London, 1991, reprint, p.1)
          Stephen E. Jones http://members.iinet.net.au/~sejones
          Moderator: http://groups.yahoo.com/group/CreationEvolutionDesign
          --------------------------------------------------------------------------
        • Cliff Lundberg
          From: Stephen E. Jones ... I don t have a quote handy at the moment, but here is the relevant ... [...] Trace fossil burrows (~1 Ga &
          Message 4 of 5 , Nov 2, 2004
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            From: "Stephen E. Jones" <sejones@...>

            > There is a show-stopper for Cliff's "reduction and distortion"
            > theory (i.e. as a *general* theory-no one denies that there has
            > been "reduction and distortion") in that all of a sudden, fossil
            > worm trails and burrows show up in what was soft seafloor
            > mud ~550 mya. Since the mud below was the same as the
            > mud the trace fossils are found in, this is the strongest
            > possible evidence that triploblastic complex worm-like adult
            > animals came into existence ~550 mya (presumably descended
            > from microscopic larval forms of which there are phosphatised
            > fossil embryos ~600 mya). There are claimed worm faecal
            > pellets ~600 mya, but this is less certain.

            I don't have a quote handy at the moment, but here is the relevant
            section out of my assignment:

            -----------------------------------------------------------------
            ---------
            [...]

            Trace fossil burrows (~1 Ga & ~550 Ma)
            Evidence of burrowing trace fossils ~1 Ga has been claimed
            (Seilacher,
            Bose & Pflüger, 1998). But this has been challenged as an
            inorganic
            pseudo-fossil (Kerr, 1998b; Rai & Gautam, 1999). However,
            undisputed
            trails and burrows have been found extending back to 550 Ma (Erwin
            &
            Davidson, 2002; Knoll & Carroll, 1999). Fossilised faecal pellets
            have also
            been found ~600 Ma (Knight, 1997). These trace fossils were
            evidently
            made by bilaterally symmetrical, worm-like animals with a
            mouth-anus
            digestive tract (Carroll, 2000). [...]
            -----------------------------------------------------------------
            ---------

            Cliff is of course free to ignore this evidence, but then he
            should not expect
            me (for starters) to take his "reduction and distortion" theory
            seriously.

            [...]

            Steve


            -----------------------------------------------------------------
            ---------
            "Biology is the study of complicated things that give the
            appearance
            of having been designed for a purpose." (Dawkins R., "The Blind
            Watchmaker," [1986], Penguin: London, 1991, reprint, p.1)
            Stephen E. Jones http://members.iinet.net.au/~sejones
            Moderator: http://groups.yahoo.com/group/CreationEvolutionDesign
            -----------------------------------------------------------------
            ---------

















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          • Cliff Lundberg
            From: Stephen E. Jones ... theory ... reduction ... burrows ... A show-stopper is supposed to be something so great that its
            Message 5 of 5 , Nov 2, 2004
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              From: "Stephen E. Jones" <sejones@...>

              > There is a show-stopper for Cliff's "reduction and distortion"
              theory
              > (i.e. as a *general* theory-no one denies that there has been
              "reduction
              > and distortion") in that all of a sudden, fossil worm trails and
              burrows
              > show up in what was soft seafloor mud ~550 mya.

              A show-stopper is supposed to be something so great that its
              acclamation is disruptive. I would not put in this category
              the claim that the worms of the early Cambrian sprouted
              limbs and jaws; that is an old and unsubstantiated staple
              of Darwinian mythology.

              The worms themselves appeared as suddenly as did the later
              vertebrates and arthropods. They too need a mechanism for
              sudden development, and here too the simple multiplication of
              bodies to form a segmented train does the trick.

              The old notion that the known animals should be arranged
              with earlier, simpler ones at the start, and more anatomically
              complex ones at the end, has proven unfruitful in understanding
              origins, or development, or historical trends, or anything else.

              Cliff
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