Posted on 05/05/2005 3:47:48 PM PDT by neverdem
Gaston Design
Dr. James I. Kirkland with a full-size cast of Falcarius utahensis, a dinosaur switching from meat to plants.
Without government nutrition guidelines, a doctor's advice or some primeval diet fad, entire species of dinosaurs sometimes forsook their predatory, meat-eating lifestyle and evolved into grazing vegetarians. Scientists now think they have found rare evidence of a species undergoing just such a dietary transition 125 million years ago.
Paleontologists in Utah announced yesterday that they had discovered a new species of dinosaurs in an intermediate stage between carnivore and herbivore, on the way to becoming a committed vegetarian. They could only speculate on the reasons for the change, but noted that it occurred in a time of global warming and the arrival of flowering plants in profusion, a tempting new food source.
Dr. James I. Kirkland, a paleontologist with the Utah Geological Survey, said the new species, named Falcarius utahensis, was uncovered two years ago at a remote dig site near the town of Green River. The animal, about 13 feet long and 4½ feet tall, was a primitive member of the therizinosaur group of feathered dinosaurs.
Under closer examination, Dr. Kirkland said, the Falcarius fossils showed "the beginnings of features we associate with plant-eating dinosaurs." The teeth were not the sharp, bladelike serrated teeth of the typical predator, but smaller and adapted for shredding leaves. "I doubt that this animal could have cut a steak," he said.
Other characteristics of an animal in transition to herbivory included an expansion of the gut to digest the mass of fermenting plants, stouter legs for supporting a bulkier body instead of the slender legs of a fast-running predator, and a lengthening of the neck, perhaps to reach for leaves higher in the trees.
Dr. Scott D. Sampson, chief curator of the Museum of Natural History at the University of Utah, said the new fossils were "amazing documentation of a major dietary shift" and promised to "tell us how this shift happened."
The scientists described and interpreted the findings in interviews and a teleconference from Salt Lake City. A detailed report is being published today in the journal Nature.
Dr. Mark A. Norell, a dinosaur specialist at the American Museum of Natural History who was not involved in the research, said the fossils were well preserved and the teeth appeared to be similar to those of plant-eating dinosaurs. But he questioned how much scientists would be able to learn from the specimen about the change from meat eating to plant eating.
Dr. Sampson said, "Falcarius represents evolution caught in the act, a primitive form that shares much in common with its carnivorous kin, while possessing a variety of features demonstrating that it had embarked on the path toward more advanced plant-eating forms."
Dr. Norell agreed that the new species "is a very important and interesting animal," primarily because it is a rare early example of the therizinosaur group in North America. Falcarius is anatomically more primitive than the better-known therizinosaurs that were prevalent in China about 90 million years ago and had already evolved as plant eaters.
Lindsay E. Zanno, a doctoral student in paleontology at Utah, said Falcarius was "the most primitive known therizinosaur, demonstrating unequivocally that this large-bodied group of bizarre herbivorous dinosaurs" came from predatory carnivores like the swift, fierce Velociraptor. Falcarius and Velociraptor had a common ancestor.
Scientists say all the vegetarian dinosaurs evolved from ancestors that were carnivores. Some 230 million years ago, the first dinosaur was presumably a small-bodied, fleet-footed predator. Then two major groups of dinosaurs, the gigantic species and the smaller duck-billed grazers, evolved as plant eaters.
As for Falcarius, scientists are not sure what it ate, meat or plants or both, and they suspect that the transition extended over several million years.
But with Falcarius, Dr. Sampson said, "we have actual fossil evidence of a major dietary shift, certainly the best example documented among dinosaurs."
James I. Kirkland
Dinosaur jaw fragments reveal teeth adapted for plant shredding.
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I'm sure the folks over at PETA would agree with the idea that becoming vegetarian is an example of evolutionary progress. :-)
Now we know the real reasons why dinosaurs became extinct. (More proof that we shouldn't give up steak!) ;)
Maybe it fulfilled the same niche bears do today, eating an omnivorious diet while on the way to full-blown vegetarianism.
That's what I thought. So maybe when we all become vegetarians, we will have evolved as far as we can.
So human evolution was a "devolution?" of sorts? We began as less advanced vegetarian primates that did not have to work for their food, animals that bred in high numbers with no significant pair-bonds (to quote Desmond Morris), animals that defecated in the same areas in which they slept.
As primates began to engage in a more carnivorous diet and had to actually kill their food, they adopted carnivore-like habits: they stopped pooping where they ate, they began forming permanent pair bonds which benefitted their children, not to mention of the increase in the size of brains.
Methinks there might be an agenda afoot in this artcicle.
Everyone has an agenda these days.
Hmmm.... relative?
That was a "well-duh" statement, wasn't it? :)
Have any of you seen pictures of what was actually found? I just want to know how many actual bones were found.
The Making of a Vegetarian Dinosaur: Evolutionists Caugth in the Act.
What do they really know? By their own admission nothing yet about its diet ("As for Falcarius, scientists aren't sure what it ate.") But that doesn't seem to discourage them from all sorts of speculations.
Now, let me get this straight...they found a dinosaur taking a dump?
"Scientists now think they have found rare evidence of a species undergoing just such a dietary transition 125 million years ago."
Wait a minute here, scientists weren't around then. From the butcher shop to the salad shop? No way.
How do they know it's not a herbivore transitioning into a carnivore?
Dr. Kirkland (pictured) is obviously NOT a vegetarian.
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