Saturday, August 18, 2012

The Teeth and Claws of Archaeopteryx


Two important points evolutionary biologists rely on when claiming Archaeopteryx was a transitional form, are the claws on its wings and its teeth.

It is true that Archaeopteryx had claws on its wings and teeth in its mouth, but these traits do not imply that the creature bore any kind of relationship to reptiles. Besides, two bird species living today, the touraco and the hoatzin, have claws which allow them to hold onto branches. These creatures are fully birds, with no reptilian characteristics. That is why it is completely groundless to assert that Archaeopteryx is a transitional form just because of the claws on its wings.

Neither do the teeth in Archaeopteryx's beak imply that it is a transitional form. Evolutionists are wrong to say that these teeth are reptilian characteristics, since teeth are not a typical feature of reptiles. Today, some reptiles have teeth while others do not. Moreover, Archaeopteryx is not the only bird species to possess teeth. It is true that there are no toothed birds in existence today, but when we look at the fossil record, we see that both during the time of Archaeopteryx and afterwards, and even until fairly recently, a distinct group of birds existed that could be categorised as "birds with teeth."

The most important point is that the tooth structure ofArchaeopteryx and other birds with teeth is totally different from that of their alleged ancestors, the dinosaurs. The well-known ornithologists L. D. Martin, J. D. Stewart, and K. N. Whetstone observed that Archaeopteryx and other similar birds have unserrated teeth with constricted bases and expanded roots. Yet the teeth of theropod dinosaurs, the alleged ancestors of these birds, had serrated teeth with straight roots.127 These researchers also compared the ankle bones of Archaeopteryxwith those of their alleged ancestors, the dinosaurs, and observed no similarity between them.128

Studies by anatomists such as S. Tarsitano, M.K. Hecht, and A.D. Walker have revealed that some of the similarities that John Ostrom and others have seen between the limbs ofArchaeopteryx and dinosaurs were in reality misinterpretations.129 For example, A.D. Walker has analyzed the ear region of Archaeopteryx and found that it is very similar to that of modern birds.130

Furthermore, J. Richard Hinchliffe, from the Institute of Biological Sciences of the University of Wales, studied the anatomies of birds and their alleged reptilian ancestors by using modern isotopic techniques and discovered that the three forelimb digits in dinosaurs are I-II-III, whereas bird wing digits are II-III-IV. This poses a big problem for the supporters of the Archaeopteryx-dinosaur link.131 Hinchliffe published his studies and observations inScience in 1997, where he wrote:
Doubts about homology between theropods and bird digits remind us of some of the other problems in the "dinosaur-origin" hypothesis. These include the following: (i) The much smaller theropod forelimb (relative to body size) in comparison with the Archaeopteryx wing. Such small limbs are not convincing as proto-wings for a ground-up origin of flight in the relatively heavy dinosaurs. (ii) The rarity in theropods of the semilunate wrist bone, known in only four species (including Deinonychus). Most theropods have relatively large numbers of wrist elements, difficult to homologize with those of Archaeopteryx. (iii) The temporal paradox that most theropod dinosaurs and in particular the birdlike dromaeosaurs are all very much later in the fossil record than Archaeopteryx.
As Hinchliffe notes, the "temporal paradox" is one of the facts that deal the fatal blow to the evolutionist allegations about Archaeopteryx. In his book Icons of Evolution, American biologist Jonathan Wells remarks that Archaeopteryx has been turned into an "icon" of the theory of evolution, whereas evidence clearly shows that this creature is not the primitive ancestor of birds. According to Wells, one of the indications of this is that theropod dinosaurs-the alleged ancestors of Archaeopteryx-are actually younger thanArchaeopteryx: "Two-legged reptiles that ran along the ground, and had other features one might expect in an ancestor of Archaeopteryx, appear later."132

All these findings indicate that Archaeopteryx was not a transitional link but only a bird that fell into a category that can be called "toothed birds." Linking this creature to theropod dinosaurs is completely invalid. In an article headed "The Demise of the 'Birds Are Dinosaurs' Theory," the American biologist Richard L. Deem writes the following aboutArchaeopteryx and the bird-dinosaur evolution claim:
The results of the recent studies show that the hands of the theropod dinosaurs are derived from digits I, II, and III, whereas the wings of birds, although they look alike in terms of structure, are derived from digits II, III, and IV... There are other problems with the "birds are dinosaurs" theory. The theropod forelimb is much smaller (relative to body size) than that of Archaeopteryx. The small "proto-wing" of the theropod is not very convincing, especially considering the rather hefty weight of these dinosaurs. The vast majority of the theropod lack the semilunate wrist bone, and have a large number of other wrist elements which have no homology to the bones of Archaeopteryx. In addition, in almost all theropods, nerve V1 exits the braincase out the side, along with several other nerves, whereas in birds, it exits out the front of the braincase, though its own hole. There is also the minor problem that the vast majority of the theropods appeared after the appearance of Archaeopteryx.133

127 L. D. Martin, J. D. Stewart, K. N. Whetstone, The Auk, vol. 97, 1980, p. 86.
128 L. D. Martin, J. D. Stewart, K. N. Whetstone, The Auk, vol. 97, 1980, p. 86; L. D. Martin, "Origins of the Higher Groups of Tetrapods", Ithaca, Comstock Publishing Association, New York, 1991, pp. 485-540.
129 S. Tarsitano, M. K. Hecht, Zoological Journal of the Linnaean Society, vol. 69, 1980, p. 149; A. D. Walker,Geological Magazine, vol. 117, 1980, p. 595.
130 A.D. Walker, as described in Peter Dodson, "International Archaeopteryx Conference," Journal of Vertebrate Paleontology 5(2):177, June 1985.
131 Richard Hinchliffe, "The Forward March of the Bird-Dinosaurs Halted?," Science, vol. 278, no. 5338, 24 October 1997, pp. 596-597.
132 Jonathan Wells, Icons of Evolution, Regnery Publishing, 2000, p. 117
133 Richard L. Deem, "Demise of the 'Birds are Dinosaurs' Theory";,"http://www.yfiles.com/dinobird2.html.

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