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Time to do some actual peer review (#2 of 3)
Do dino fossils support evolution?
Last summer the dinosaurs returned! From June through early September, The
Dinosaur World Tour: The Greatest Show Unearthed appeared at Vancouver's
PNE Forum, and captivated tens of thousands of children and adults alike.
The Tour is a sprawling $20 million multi-media show which includes 30
complete dinosaur skeletons and 11 new never-before seen dinosaur species,
including the amazing 20 ton, 30 metre long Mamenchisurus from China. The
Tour has also received rave reviews in Edmonton, Toronto and Osaka where
it was witnessed by over one million enthusiastic viewers. Combined with
hands-on displays, multi-media technology, and digital dinosaur sounds, the
exhibit is hailed as one of the top ten exhibits of the '90s.
The 14,000 square feet Carnosaurs exhibit is currently on display at
Edmonton's Provincial Museum, where close to 175,000 visitors are expected
over its 6 1/2 month run. Carnosaurs features 13 life-size robotic
dinosaurs in a Jurassic Park setting, and includes everything from CD-ROM
technology to an eight-metre tall Tyrannosaurus Rex.
Many Albertans will recall July's discovery in Dinosaur Provincial Park of
Struthiomimus, a dinosaur skeleton from the family of ornithomimids ("bird
mimics"). Philip Currie, head of dinosaur research at the Tyrrell Museum,
told the Calgary Herald : "These guys look like ostriches without the
feathers...they're built to move fast." (Calgary Herald, July 19, p. A1).
It is interesting that dinosaurs that had long slim legs, small lightweight
bodies, and in general appearance look somewhat like birds, such as ostrich
mimic Struthiomimus, were "lizard-hipped". Conversely, dinosaurs that look
more like low-slung tanks than graceful birds (eg. Ankylosaurus) were
"bird-hipped". Therefore, one question that should be put to dinosaur
experts is: If dinosaurs evolved into birds, wouldn't we expect to see
"bird-hipped" dinosaurs looking more bird-like rather than the reverse?
The notion that dinosaurs and birds are related dates back to the 1861
discovery of a pigeon-size fossil named Archaeopteryx, which had a
bird-like skull, perching feet, and was a powered flyer, with wings of the
basic pattern and proportions of the modern avian wing. It also had
feathers identical to modern flying birds. Evolutionary scientists believe
Archaeopteryx was a transitional creature---related to dinosaurs but well
along the evolutionary pathway to modern birds. Other scientists say that
the fact it had claws on its wings does not necessarily indicate reptilian
ancestry; they cite three birds living today---the South American hoatzin,
African touraco, and ostrich---as each having claws on its wings and yet
are true birds. Although Archaeopteryx had teeth, considered to be another
reptilian feature, some fossil birds had teeth and some did not. That this
should be true is not surprising, since this is true of all other classes
of vertebrates---fish, amphibians, reptiles and mammals.
In 1993 some paleontologists hailed a small creature named Mononychus as "a
new link between dinosaurs and birds" because it shares some features with
modern birds, such as a keeled sternum and some fused wristbones. (On the
April 26/93 Time cover, the creature is drawn having feathers instead of
scales, which is entirely speculative.) And according to Barbara Stahl, in
Vertebrate History: Problems in Evolution, (pp. 349-350) "how [feathers]
arose initially, presumably from reptiles scales, defies analysis...It
seems, from the complex construction of feathers, that their evolution from
reptilian scales would have required an immense period of time and involved
a series of intermediate structures. So far, the fossil record does not
bear out that supposition."
Paleontologists say that in order for a complete dinosaur to fossilize, it
had to be rapidly buried in large quantities of sediment. The contorted
appearance of many skeletons suggest burial of dinosaurs which died in
agony, or of freshly dead dinosaurs whose limbs were distorted by the
sediment load and rapid water current which carried the load. [The Tyrrell
paleontologists report that the ornithomimid was found in the "classic
death pose" with neck and tail dramatically curved.]
But could local slides and floods account for the formation of all dinosaur
fossils, as well as billions of other fossil creatures found over the
entire planet, from the highest mountains to the lowest canyons? Dr. Duane
Gish, in his book Evolution: The Challenge of the Fossil Record asks: "If
dinosaurs evolved from other reptiles over millions of years, why do we not
find even one example of a transitional form in the fossil record?" Gish
points out that paleontologists have never found, for example, any evidence
that Stegosaurus evolved from an earlier form, showing the gradual
development of tail spikes, plates, etc. He says this is true of every
dinosaur ever found, whether Brachiosaurus, Tyrannosaurus, [Tyrannosaurus
skeleton "Scotty" is currently being excavated near Eastend, Saskatchewan]
or any other dinosaur; each type appears in the fossil record fully formed,
right from the start.
Added support for Gish's argument is the recent discovery in western
Argentina of what may be the largest meat-eating dinosaur known, a
12.5-metre-tall dinosaur christened Giganotosaurus carolinii (Nature, Sept.
21). Despite the overall similarity in appearance to T. rex, according to
Argentinian paleontologist Rodolfo Coria, Giganotosaurus was not related to
it, and the two beasts "arose independently".
To explain why transitional fossils are NOT found, Niles Eldredge and
Stephen Jay Gould (1972) came up with the "punctuated equilibria" model of
evolution, which is unique. It must be the only theory put forth in the
history of science which claims to be scientific, but then explains why
evidence for it cannot be found.
The fossil record stands as a silent witness to the abrupt appearance of
dinosaurs on the earth. If dinosaurs evolved from other reptiles and then
evolved into birds (remember the ending of Jurassic Park?) there certainly
isn't any evidence for it in the fossil record.
* David A. Buckna is a public school teacher in Kelowna, British Columbia,
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