Posted on 08/13/2003 9:02:05 PM PDT by nwrep
2 hours, 55 minutes ago
|
|
By RAMOLA TALWAR BADAM, Associated Press Writer
BOMBAY, India - U.S. and Indian scientists said Wednesday they have discovered a new carnivorous dinosaur species in India after finding bones in the western part of the country.
|
The new dinosaur species was named Rajasaurus narmadensis, or "Regal reptile from the Narmada," after the Narmada River region where the bones were found.
The dinosaurs were between 25-30 feet long, had a horn above their skulls, were relatively heavy and walked on two legs, scientists said. They preyed on long-necked herbivorous dinosaurs on the Indian subcontinent during the Cretaceous Period at the end of the dinosaur age, 65 million years ago.
"It's fabulous to be able to see this dinosaur which lived as the age of dinosaurs came to a close," said Paul Sereno, a paleontologist at the University of Chicago. "It was a significant predator that was related to species on continental Africa, Madagascar and South America."
Working with Indian scientists, Sereno and paleontologist Jeff Wilson of the University of Michigan reconstructed the dinosaur skull in a project funded partly by the National Geographic (news - web sites) Society.
A model of the assembled skull was presented Wednesday by the American scientists to their counterparts from Punjab University in northern India and the Geological Survey of India during a Bombay news conference.
Scientists said they hope the discovery will help explain the extinction of the dinosaurs and the shifting of the continents how India separated from Africa, Madagascar, Australia and Antarctica and collided with Asia.
The dinosaur bones were discovered during the past 18 years by Indian scientists Suresh Srivastava of the Geological Survey of India and Ashok Sahni, a paleontologist at Punjab University.
When the bones were examined, "we realized we had a partial skeleton of an undiscovered species," Sereno said.
The scientists said they believe the Rajasaurus roamed the Southern Hemisphere land masses of present-day Madagascar, Africa and South America.
"People don't realize dinosaurs are the only large-bodied animal that lived, evolved and died at a time when all continents were united," Sereno said.
The cause of the dinosaurs' extinction is still debated by scientists. The Rajasaurus discovery may provide crucial clues, Sereno said.
India has seen quite a few paleontological discoveries recently.
In 1997, villagers discovered about 300 fossilized dinosaur eggs in Pisdura, 440 miles northeast of Bombay, that Indian scientists said were laid by four-legged, long-necked vegetarian creatures.
Indian scientists said the dinosaur embryos in the eggs may have suffocated during volcanic eruptions.
And here I thought they were referring to the American IT worker.
And most have not. Furthermore, recent discoveries have filled in even more of the "missing links" in the dinosaur-to-bird transition. More information. Another excellent site. Here's an amusing excerpt from that last link:
And really, the Birds-Are-Not-Dinosaurs (BAND) group seriously are a constant source of amusement to me. As soon as one theory on why birds cannot be dinosaurs is demolished by a new discovery, the BAND crowd come up with a new theory that is even less plausible than their previous one. Over the past few years, these folks have adopted more positions than the Kama Sutra.
Archaeopteryx [...] was not a dinosaur. It was a bird.
It's always funny listening to creationists try to explain Archaeopteryx. The reason it's so funny is that half of them declare it to be "obviously" just a bird -- and the other half declare it to be "obviously" just a reptile.
So it's a bird, eh? Well that explains the wings and feathers and so on. But how then do you explain these clearly reptilian features?
Premaxilla and maxilla are not horn-covered. This is posh talk for "does not have a bill."[The above condensed from All About Archaeopteryx by Chris Nedin, which has far more information and quotes from primary research.Trunk region vertebra are free. In birds the trunk vertebrae are always fused.
Pubic shafts with a plate-like, and slightly angled transverse cross-section. A Character shared with dromaeosaurs but not with other dinosaurs or birds.
Cerebral hemispheres elongate, slender and cerebellum is situated behind the mid-brain and doesn't overlap it from behind or press down on it. This again is a reptilian feature. In birds the cerebral hemispheres are stout, cerebellum is so much enlarged that it spreads forwards over the mid-brain and compresses it downwards.
Neck attaches to skull from the rear as in dinosaurs not from below as in modern birds. The site of neck attachement (from below) is characteristic in birds, _Archaeopteryx_ does not have this character, but is the same as theropod dinosaurs.
Center of cervical vertebrae have simple concave articular facets. This is the same as the archosaur pattern. In birds the vertebrae are different, they have a saddle-shaped surface: "The most striking feature of the vertebrae is the simple disk-like facets of their centra, without any sign of the saddle-shaped articulations found in other birds" (de Beer 1954, p. 17).
Long bony tail with many free vertebrae up to tip (no pygostyle). Birds have a short tail and the caudal vertebrae are fused to give the pygostyle.
Premaxilla and maxilla bones bear teeth. No modern bird possess teeth.
Ribs slender, without joints or uncinate processes and do not articulate with the sternum. Birds have stout ribs with uncinate processes (braces between them) and articulate with the sternum.
Pelvic girdle and femur joint is archosaurian rather than avian (except for the backward pointing pubis as mentioned above).
The Sacrum (the vertebrae developed for the attachment of pelvic girdle) occupies 6 vertebra. This is the same as in reptiles and especially ornithipod dinosaurs. The bird sacrum covers between 11-23 vertebrae!
Metacarpals (hand) free (except 3rd metacarpal), wrist hand joint flexible. This is as in reptiles. In birds the metacarpals are fused together with the distal carpals in the carpo-metacarpus, wrist /hand fused.
Nasal opening far forward, separated from the eye by a large preorbital fenestra (hole). This is typical of reptiles, but not of birds.
Deltoid ridge of the humerus faces anteriorly as do the radial and ulnar condyles. Typical of reptiles but not found in birds.
Claws on 3 unfused digits. No modern adult bird has 3 claws, nor do they have unfused digits.
The fibula is equal in length to the tibia in the leg. This again is a typical character of reptiles. In birds the fibula is shortened and reduced. [When you eat a chicken drumstick, the fibula is the toothpick-like sliver of bone you find lying alongside the large "legbone", which is the tibia. Ich.]
Metatarsals (foot bones) free. In birds these are fused to form the tarsometatarsus.
Gastralia present. Gastralia are "ventral ribs," elements of dermal bone in the ventral wall of the abdomen. Typical of reptiles, they are absent in birds
Are you sure you know what you're talking about?
I have to warn you, if you've gotten your "information" from creationist sources, you've likely been woefully misinformed and underinformed.
(unlike Archaeoraptor which was a known hoax)
That's overstating the case. It's more accurate to say it was a fraud. And not by those evil(tm) evolutionists, either, as creationists like to imply. More than anything else, it was a comedy of errors.
The Chinese farmer who found the original specimen knew that it would sell for more money to fossil collectors if it was more complete, so he shaped and glued plausible (to him) pieces he had found nearby onto a broken specimen. He was just trying to make a buck, not hoax anyone into any particular scientific conclusion.
It was eventually bought by a husband-wife team of semi-professional fossil collectors (dubbed "hobbyists" in some accounts), who decided they had something interesting and brought it to the attention of National Geographic magazine, hoping for fame and fortune. If it turned out to be significant, it could be their Big Break in the fossil community.
National Geographic normally doesn't publish new discoveries without first having them peer-reviewed in advance by scientists (even though, note, National Geographic is not itself a "scientific" publication). For various reasons they neglected to do so this time, and the result was egg on their faces.
Through a number of communication failures, red flags raised by several members of the team examining the specimen were not communicated to the right people (some of which were out in the field working on other projects), and eventually National Geographic went to press with an announcment of a new "discovery" that turned out to have been incorrectly assembled like a jigsaw puzzle. (Note: The fact that the specimen was glued together in several places was not itself a tip-off, since specimens are often broken into several pieces naturally prior to being discovered, or broken during recovery, and then glued together to retain their form.)
It was only a matter of weeks before the attention created by the publication resulted in a flood of scientists pointing out the obviously inauthentic nature of the specimen, and National Geographic published an embarrassed retraction and post-mortem analysis of how they had managed to screw up.
Significantly, the two *science* journals to which the fossil owners had submitted papers on the specimen (prior to the National Geographic publication) had rejected them. The journal Nature rejected it because National Geographic would not give them enough time to properly peer review the matter before NG's publication, and they would not print it without peer review (good for them, this is why peer-review is a critical scientific "reality check").
The paper was then submitted to the journal Science, which rejected it, saying they required more proof of Archaeoraptor's birdlike qualities. The paper was rewritten and resubmitted, and again rejected as inadequate.
So contrary to creationist claims about this debacle, 1) the fraud was perpetrated by a Chinese farmer out to make a buck, not an agenda-driven scientist, 2) the mass-market magazine National Geographic was responsible for the premature announcement of its alleged "missing link" status, not the science community nor science journals, 3) actual science journals rejected it, and 4) scientists were the first to identify it as a fraud as soon as they got a look at it.
Rather than being a story of science's alleged frauds or errors, it's actually a story of how self-correcting science is.
This much is correct.
Clarification on my previous post (which I'll admit was a little confusing). Lizards are ectotherms as opposed to endotherms.
And so is this.
Dinosaurs are also ectotherms as well. They are just great big lizards, in other words.
This, on the other hand... Dinosaurs may or may not have been ectotherms. There's a lot of debate and contradictory evidence about that. One of the latest views is that they actually had some features of both ectothermic and endothermic metabolisms (i.e., it may not be either-or, they may have been sort of in-between).
But even if they were ectothermic, that does *not* make them "big lizards". Ectothermia is hardly the defining characteristic of what makes a reptile a lizard. If it were, turtles and snakes would be "lizards" as well, and they're not.
Dinosaurs are their own distinct category, as specialized and different from lizards as lizards are from snakes/turtles.
And when you aren't watching, they eat from your table.
Cite, please.
Many many years ago most scientists believed the earth was flat
Which scientists, when?
(incidentally, the Bible has always claimed the earth was round).
Round, as in a flat disk.
These theories range anywhere from the traditional big-bang primordial soup gig to panspermia (which is a position held by DNA co-founder Francis Crick stating that the world shows intelligent design, but OBVIOUSLY we can't admit God could have done all this, so the aliens came here millions and millions of years ago and planted seeds- boy that's science!
Crick wrote one paper discussing the possibility of panspermia. He has not to my knowledge ever stated the world shows intelligent design.
Oh my. I'm certain you have plenty of evidence to support both the contentions you made above, otherwise you wouldn't have made them. I'd like to see what you've got, if you don't mind.
No, we don't. However, the Bible teaches man was formed from dirt, so one could make the claim that that which you attribute to evolutionists more accurately portrays creationists.
Actually, dinosaurs are now considered a separate group, descended from reptiles (as were mammals) but with unique features setting them apart from reptiles.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.