Re: But is it science?

From: Susan Brassfield Cogan (Susan-Brassfield@ou.edu)
Date: Wed Sep 20 2000 - 15:11:31 EDT

  • Next message: Bertvan@aol.com: "Blood clotting and IC'ness?"

    Hi Bertvan!
    I'm impressed! this is a much greater attempt to post some evidence of
    claims instead of just cutting and pasting the same tired assertations you
    have made a bajillion times in the past.

    >. . . Darwinism, the idea that nature is the result of chance events
    >molded by natural selection, included some good stories. Such as the one
    >about how a wolf-like creature turned into a whale in a mere 10 million years.
    >
    >Some of the changes would have included:
    >(1) Complete loss of body hair

    etc.

    >http://www.arn.org/ubb/Forum1/HTML/000320.html
    >(See post by DNAunion 9-19-2000)

    I plan to check it out.

    >All of these changes *might* be explained by some implausible "chance events
    >plus natural selection" scenario. However, any story of how it might have
    >happened is pure science fiction.

    The history of the whales is pretty well documented, which is why
    creationists are so anxious to say it doesn't exist. The following is
    pretty long, you may want to read only the introductory paragraph. I
    included the rest just for general intersest. This and a lot of nice stuff
    as at: http://cns-web.bu.edu/pub/dorman/trans_faq.html#ceta

    8. CETACEANS (WHALES, DOLPHINS)

    Just several years ago, there was still a large gap in the fossil record
    of the cetaceans. It was thought that they arose from land-dwelling
    mesonychids that gradually lost their hind legs and became aquatic.
    Evolutionary theory predicted that they must have gone through a stage
    where they had were partially aquatic but still had hind legs, but there
    were no known intermediate fossils. A flurry of recent discoveries from
    India & Pakistan (the shores of the ancient Tethys Sea) has pretty much
    filled this gap. There are still no known species-species transitions,
    and the "chain of genera" is not complete, but we now have a partial
    lineage, and sure enough, the new whale fossils have legs, exactly as
    predicted. (for discussions see Berta, 1994; Gingerich et al. 1990;
    Thewissen et al. 1994; Discover magazine, Jan. 1995; Gould 1994)

    Eoconodon or similar triisodontine arctocyonids (early Paleocene)
       Unspecialized condylarths quite similar to the early oxyclaenid
       condylarths, but with strong canine teeth (showing first meat-eating
       tendencies), blunt crushing cheek teeth, and flattened claws instead
       of nails.
    Microclaenodon (mid-Paleocene)
       A transitional genus intermediate between Eoconodon and the
       mesonychids, with molar teeth reorganizing in numerous ways to look
       like premolars. Adapted more toward carnivory.
    Dissacus (mid-Paleocene)
       A mesonychid (rather unspecialized Paleocene meat-eating animal) with
       molars more like premolars & several other tooth changes. Still had
       5 toes in the foot and a primitive plantigrade posture.
    Hapalodectes or a very similar mesonychid (early Eocene, around 55 Ma)
       A small mesonychid with very narrow shearing molars, a distinctively
       shaped zygomatic arch, and peculiar vascularized areas between the
       molars. Probably a running animal that could swim by paddling its
       feet. Hapalodectes itself may be just too late to be the whale
       ancestor, but probably was a close relative of the whale ancestor.
       Says Carroll (1988): "The skulls of Eocene whales bear unmistakable
       resemblances to those of primitive terrestrial mammals of the early
       Cenozoic. Early [whale] genera retain a primitive tooth count with
       distinct incisors, canines, premolars,, and multirooted molar teeth.
       Although the snout is elongate, the skull shape resembles that of the
       mesonychids, especially Hapalodectes...."
    Pakicetus (early-mid Eocene, 52 Ma)
       The oldest fossil whale known. Same skull features as
       Hapalodectes, still with a very terrestrial ear (tympanic membrane,
       no protection from pressure changes, no good underwater sound
       localization), and therefore clearly not a deep diver. Molars still
       have very mesonychid-like cusps, but other teeth are like those of
       later whales. Nostrils still at front of head (no blowhole). Whale-
       like skull crests and elongate jaws. Limbs unknown. Only about 2.5
       m long. This skull was found with terrestrial fossils and may have
       been amphibious, like a hippo.
    Ambulocetus natans (early-mid Eocene, 50 Ma)
       A recently discovered early whale, with enough of the limbs and
       vertebrae preserved to see how the early whales moved on land and in
       the water. This whale had four legs! Front legs were stubby. Back
       legs were short but well-developed, with enormous broad feet that
       stuck out behind like tail flukes. Had no true tail flukes, just a
       long simple tail. Size of a sea lion. Still had a long snout with
       no blowhole. Probably walked on land like a sea lion, and swam with
       a seal/otter method of steering with the front feet and propelling
       with the hind feet. So, just as predicted, these early whales were
       much like modern sea lions -- they could swim, but they could also
       still walk on land. (Thewissen et al., 1994)
    Rodhocetus (mid-Eocene, 46 Ma)
       Another very recent (1993) fossil whale discovery. Had hind legs a
       third smaller than those of A. natans. Could probably still
       "waddle" a bit on land, but by now it had a powerful tail (indicated
       by massive tail vertebrae) and could probably stay out at sea for
       long periods of time. Nostrils had moved back a bit from the tip of
       the snout.
    Basilosaurus isis, Protocetes, Indocetus ramani and similar small-
    legged whales of the mid-late Eocene (45-42 Ma)
       After Rodhocetus came several whales that still had hind legs, but
       couldn't walk on them any more. For example, B. isis (42 Ma) had
       hind feet with 3 toes and a tiny remnant of the 2nd toe (the big toe
       is totally missing). The legs were small and must have been useless
       for locomotion, but were specialized for swinging forward into a
       locked straddle position -- probably an aid to copulation for this
       long-bodied, serpentine whale. B. isis may have been a "cousin" to
       modern whales, not directly ancestral. Another recent discovery is
       Protocetes, a slightly more advanced whale from the late Eocene.
       It was about 3m long (dolphin sized), and still had primitive
       dentition, nostrils at end of snout, and a large pelvis attached to
       the spine; limbs unknown. Finally Indocetus is known from only
       fragmentary remains, but these include a tibia. These late Eocene
       legged whales still had mesonychid-like teeth, and in fact, some of
       the whale fossils were first mis-identified as mesonychids when only
       the teeth were found. ( See Gingerich et al. (1990) for more info on
       B. isis.)
    Prozeuglodon (late Eocene, 40 Ma)
       Another recently discovered whale, found in 1989. Had *almost* lost
       the hind legs, but not quite: still carried a pair of vestigial 6-
       inch hind legs on its 15-foot body.
    Eocetus, & similar "archeocete whales" of the late Eocene
       These more advanced whales have lost their hind legs entirely, but
       retain a"primitive whale" skull and teeth, with unfused nostrils.
       They grew to larger body size (up to 25m by the end of the Eocene),
       an had an elongate, streamlined body, flippers, and a cartilaginous
       tail fluke. The ear was modified for hearing underwater. Note that
       this stage of aquatic adaptation was attained about 15 million years
       after the first terrestrial mesonychids.
    Dorudon intermedius -- a late Eocene whale probably ancestral to
       modern whales.

    In the Oligocene, whales split into two lineages:
    1) Toothed whales:
    Agorophius (late Oligocene)
       Skull partly telescoped, but cheek teeth still rooted. Intermediate
       in many ways between archaeocetes and later toothed whales.
    Prosqualodon (late Oligocene)
       Skull fully telescoped with nostrils on top (blowhole). Cheek teeth
       increased in number but still have old cusps. Probably ancestral to
       most later toothed whales (possibly excepting the sperm whales?)
    Kentriodon (mid-Miocene)
       Skull telescoped, still symmetrical. Radiated in the late Miocene
       into the modern dolphins and small toothed whales with asymmetrical
       skulls.
    2) Baleen (toothless) whales:
    Aetiocetus (late Oligocene)
       The most primitive known mysticete whale and probably the stem group
       of all later baleen whales. Had developed mysticete-style loose jaw
       hinge and air sinus, *but* still had all its teeth. Later,
    Mesocetus (mid-Miocene) lost its teeth.
    Modern baleen whales first appeared in the late Miocene.

    ----------

     I am aware that the conclusions arrived at in this work will be denounced
    by some as highly irreligious; but he who denounces them is bound to shew
    why it is more irreligious to explain the origin of man as a distinct
    species by descent from some lower form, through the laws of variation and
    natural selection, than to explain the birth of the individual through the
    laws of ordinary reproduction.

    ---Charles Darwin

    http://www.telepath.com/susanb/



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