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Rebuttal to Dr. Bert from T.O.!

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  • rlbaty50
    http://groups.google.com/groups? hl=en&lr=&safe=off&selm=j0lpq09gbodlqoi6dd52bup3n1jg109qup% 404ax.com&rnum=5 From: Augray (augray@sympatico.ca) Subject: Re:
    Message 1 of 1 , Dec 1, 2004
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      From: Augray (augray@...)
      Subject: Re: commentary on November 2004 National Geographic
      Newsgroups: talk.origins
      Date: 2004-11-30 13:14:40 PST

      First of all, I'm sorry this took so long, but really life kept
      calling.

      First of all, the "reconstruction" of Archaeoraptor is terrible, and
      has only a vague similarity what the National Geographic picture
      looked like. Compare their "reconstruction" with the picture in
      http://www.canoe.ca/CNEWSScience0004/07_dinosaur.html which is what
      was shown in National Geographic. A larger version can be found at
      http://gameday.onlineathens.com/images/012200/fossil.jpg

      Note that the wings in the photo have visible claws (a common trait of
      early birds), where as the "reconstruction" doesn't. The model in the
      photo has feathers on its tail, while the "reconstruction" doesn't.

      In the "Alleged Reptile-to-Bird Evolution" section, the writers quote
      Othniel Marsh, who wrote "He is certainly a wise man who today can
      tell a bird from a reptile, with only the fragments of an ancient
      form before him". I don't have quick access to the source of this
      quote, but I'm pretty sure that he wasn't referring to
      _Archaeopteryx_. Marsh had discovered several fossil birds in western
      America by that point, some of them fragmentary. I'm going to track
      down this quote through interlibrary loan.

      Sir Richard Owen is cited as believing that _Archaeopteryx_ was
      "unequivocally a bird", and this is correct. However, the only known
      skeleton of _Archaeopteryx_ at that time, which Owen had studied,
      lacked both a skull and a sternum, and Owen assumed that it had a
      beak, no teeth, and had a keel on its sternum (used in modern birds
      for the attachment of flight muscles, the "breast" of chicken and
      turkey dinners). But later specimens showed Owen to be wrong. He had
      based his conclusions on his "Law of Correlation", an early
      competitor to Darwin's Natural Selection.

      We're now treated to a quote from Alan Feduccia, who states

      Paleontologists have tried to turn Archaeopteryx into an
      earth-bound, feathered dinosaur. But it's not. It is a bird, a
      perching bird. And no amount of 'paleobabble' is going to change
      that. [Morell 1993]

      This is from an article in the journal Science that summarized
      different opinions regarding _Archaeopteryx_ as an introduction to a
      paper by Feduccia (1993) in the same issue. It was written to counter
      claims that _Archaeopteryx_ was descended from dinosaurs, lived on
      the ground, and that flight evolved "from the ground up", an idea
      championed by John Ostrom (1974). And a few paragraphs later, we're
      treated to a quote from that paper:

      I conclude that _Archaeopteryx_ was arboreal and volant,
      considerably advanced aerodynamically, and probably capable of
      flapping, powered flight to at least some degree.
      _Archaeopteryx_...was, in the modern sense, a bird.
      [Feduccia 1993]

      But what's omitted by the ellipses? The full sentence is:

      _Archaeopteryx_ probably cannot tell us much about the early
      origins of feathers and flight in true protobirds because
      _Archaeopteryx_ was, in the modern sense, a bird.

      In other words, _Archaeopteryx_ is to far along the evolutionary path
      to birds to tell us anything about the origin of feathers and flight.
      But Feduccia still believes that it's a transitional form. In the
      same paper he states that

      Most likely, _Archaeopteryx used the claws of the manus [hand]
      for
      clinging to branches because it had not yet achieved the balance
      that is characteristic of modern birds.

      He also writes that:

      Archaeopteryx was probably incapable of taking off from the
      ground;...

      Obviously Archaeopteryx wasn't a strong flyer, another characteristic
      we'd expect from a transitional form. And lest there be any doubt,
      Feduccia has stated that:

      Creationists are going to distort whatever arguments come up, and
      they've put me in company with luminaries like Stephen Jay Gould,
      so it doesn't bother me a bit. _Archaeopteryx_ is half reptile
      and
      half bird any way you cut the deck, and so it is a Rosetta stone
      for evolution, whether it is related to dinosaurs or not. These
      creationists are confusing an argument about minor details of
      evolution with the indisputable fact of evolution: Animals and
      plants have been changing. The corn in Mexico, originally the
      size of the head of a wheat plant, has no resemblance to
      modern-day corn. If that's not evolution in action, I do not know
      what is. [Svitil 2003]

      We now turn to _Mononykus_, a purported bird that was first announced
      in 1993. Initially named _Mononychus_ (Perle et al. 1993a), it was
      quickly renamed a few months later when it was discovered that
      _Mononychus_ was already the name of a genus of insect (Perle et al.
      1993b). It was initially claimed to be a bird due to several skeletal
      similarities, and that it was more closely related to modern birds
      than _Archaeopteryx_ was. This caused a storm of controversy, with
      several scientists asserting that _Mononykus_ was closely related to
      birds, but not one itself. And in the years since, three of the four
      authors of the original paper have produced family trees that show
      _Mononykus_ *not* to be a bird, but closely related to them (Clark et
      al. 2002; Chiappe 2002). However, there's no doubt that its short
      forelimbs weren't used for flight. What they *were8 used for is a bit
      of a mystery, although digging or tearing open termite mounds has
      been suggested.

      Which brings us to the following quote supplied by Thompson and
      Harrub:

      Mongolian and U.S. researchers have found a 75-million-year-old,
      bird-like creature with a hand so strange it has left
      paleontologists grasping for an explanation.... Paul Sereno of
      the
      University of Chicago notes that Mononychus had arms built much
      like those of digging animals. Because moles and other diggers
      have
      keeled sternums and wrists reminiscent of birds, the
      classification
      of Mononychus becomes difficult, he says. [Monastersky 1993]

      This provokes Thompson and Harrub to state "Thus, evolutionists now
      are faced with the possibility that birds may have evolved from moles
      instead of reptiles!" This is a gross misrepresentation, and there's
      no doubt in anyone's mind that _Mononykus_ is a theropod dinosaur (a
      grouping that includes birds), and no one claims that it's an ancestor
      to modern birds. Where Thompson and Harrub have placed ellipses in the
      quote, there are six paragraphs missing, which is most of the short
      article. But absolutely no one claims, or even hints at the
      possibility that birds evolved from moles. What Sereno is stating is
      that a lineage of dinosaurs may have evolved powerful forelimbs for
      digging, reminiscent of the powerful forelimbs needed for flight.
      Powerful forelimbs are not, in and of themselves, an indication of
      flight, or affinity with birds.

      For more on Colin Patterson, see
      http://www.talkorigins.org/faqs/patterson.html

      Now we're treated to _Protoavis_. Most paleontologists don't believe
      that it's what is discoverer, Sankar Chatterjee, says it is, and even
      Chatterjee doesn't see it being a problem for _Archaeopteryx_, or
      evolution in general (Chatterjee 1997). The following quotes are from
      references used by Thompson and Harrub:

      _Protoavis_ also has reptilian features: four teeth in the
      forward
      part of its jaw, a tail and clawed fingers.
      [Beardsley 1986]

      Much of its anatomy--including its toothy jaws--resembles a small
      meat-eating dinosaur. [Anderson 1991]

      While some of the bones appear bird-like, they also look
      dinosaurian, and could represent a new type of theropod
      dinosaur...
      [Monastersky 1991]

      _Protoavis_ is based on extremely fragmentary remains, and
      interpreting what kind of creature it is is difficult:

      Ostrom stresses, however, that the remains are very fragmentary,
      and while agreeing with Chatterjee's tentative classification
      says
      the case is not finally proven. [Beardsley 1986]

      Gauthier, who has examined the actual _Protoavis_ specimens, says
      most of the bones are poorly preserved, making it extremely
      difficult to identify many of the features that important to
      Chatterjee's argument. "It's crushed, smooshed and in really
      terrible shape," he says. [Monastersky 1991]

      The material has become a paleontological Rorschach test of one's
      training, theoretical bias, and predisposition.
      [Padian & Chiappe 1998]

      _Protoavis_, based on disarticulated bones from the Upper
      Triassic
      Dockum Formation of Texas, has not been accepted as avian by most
      researchers and is regarded here as a chimera [a mix of two or
      more
      animals] composed of several disparate Triassic reptiles. The
      four-digit manus [hand, or in this case, wing], for example, is
      more appropriately identified as an archosaurian pes [foot].
      [Sereno 1997, 460]

      The picture of the "_Archaeopteryx_lithographica_ fossil" is not what
      it is claimed to be. It looks like a parody of the real thing, or
      something that might have been done by a child in art class. It's a
      fake.

      Thompson and Harrub also claim that there are "colossal differences in
      reptilian and bird lungs", but such claims have been discredited as
      they relate to the evolution of birds (Paul 2001). As well,
      precursors to flight feathers have been found (Chen et al. 1998;
      Currie & Chen 2001; Padian et al. 2001; Schweitzer 2001; Schweitzer
      et al. 1999; Xing et al. 1999; Xu et al. 2001).

      Thompson and Harrub write that there are problems with "the
      embryological hand development of dinosaurs versus birds", but since
      no one knows how the hands of extinct dinosaurs developed, their
      claim is baseless.


      REFERENCES

      Anderson, A. 1991. Early Bird Threatens _Archaeopteryx_'s Perch.
      Science 253:35.

      Beardsley, T. 1986. Fossil bird shakes evolutionary hypothesis.
      322:677.

      Chatterjee, S. 1997. The Rise of Birds. Baltimore: The John Hopkins
      University Press.

      Chen, P.-J., Dong, Z. M., and Zheng, S.-N. 1998. An exceptionally
      well-preserved theropod dinosaur from the Yixian Formation of China.
      Nature 391:147-152.

      Chiappe, L. M. 2002. Basal Bird Phylogeny: Problems and Solutions. In
      "Mesozoic Birds: Above the Heads of Dinosaurs", edited by Luis M.
      Chiappe & Lawrence M. Witmer, pp. 448-472. Berkeley: University of
      California Press.

      Clark, J. M., Norell, M. A., & Makovicky, P. J. 2002. Cladistic
      Approaches to the Relationships of Birds to Other Theropod Dinosaurs.
      In "Mesozoic Birds: Above the Heads of Dinosaurs", edited by L. M.
      Chiappe & L. M. Witmer, pp. 31-61. Berkeley: University of California
      Press.

      Currie, P. J., & Chen, P.-J. 2001. Anatomy of _Sinosauropteryx prima_
      from Liaoning, northeastern China. Canadian Journal of Earth Sciences
      38(12):1705-1727.

      Feduccia, A. 1993. Evidence from Claw Geometry Indicating Arboreal
      Habits of _Archaeopteryx_. Science 259:790-792.
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