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burung dinosaur found in CHINA !!!???
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http://www.smh.com.au/ffximage/2007/06/14/dinosaur_wideweb__470x265,0.jpg
Never mind Sesame Street. One of the world's most renowned fossil hunters has discovered the original Big Bird -- a partly-feathered dinosaur, believed to be a distant cousin of modern birds, that weighed 3,100-pounds and stood nearly 26 feet tall.
Gigantoraptor erlianensis, discovered in China's Inner Mongolia, is the largest bird-like dinosaur ever found, capable of going eyeball to eyeball with the fearsome Tyrannosaurus rex, according to researchers.
Scientists worldwide were stunned by the size of the beast, the largest new dinosaur dug up in years and the first true behemoth of the bird-like dinosaurs. Such creatures rarely exceeded a body mass of 90 pounds and were usually much smaller.
"Imagine finding a mouse the size of a very big pig," said paleontologist Xu Xing in an interview from Beijing. "We were most amazed to find this."
Xu described his discovery in an article in today's issue of Nature, the British science journal.
Gigantoraptor possessed a parrot-like beak, no teeth, and may have sported a fringe of feathers on arms that ended in wickedly sharp claws, based on analysis of the fossils. It was 35 times heavier than similar known "oviraptors," bird-like dinosaurs that stalked the fern thickets and forests of the Late Cretaceous period, about 70 to 80 million years ago.
"Usually, oviraptors are pretty small animals, but this beast was huge," said Mark A. Norell, paleontologist at the American Museum of Natural History in New York City and himself a top fossil hunter who has worked with Xu, but not on this particular find. "This shows the incredible body diversity among these creatures."
The discovery of Gigantoraptor appears to upset prevailing evolutionary theories that dinosaurs grew smaller and smaller as they became more bird-like, according to Xu, a paleontologist with China's Academy of Sciences.
"Dinosaur evolution is a complicated process," he said. "There are still species that are beyond imagination. We need to work even harder to find even more fossils of this fascinating group."
Big as it was, the Gigantoraptor wasn't even fully grown, according to Xu. The dinosaur was "only age 11 when it died, it had not reached its full size, it had some growing to do, and a full-sized Gigantoraptor would have been considerably heavier," he said. "This was basically a growing adolescent."
The Gigantoraptor presented such a puzzle it took two years of intensive study before Xu and his colleagues felt confident enough to pronounce it a new species.
The flightless creature's feathers, Xu speculated, might have been for show -- perhaps mating display -- and possibly for keeping eggs warm. It had a small head and long neck, characteristic of herbivorous species. But it also had big talons, capable of ripping flesh, and long legs suitable for chasing prey.
In size, Gigantoraptor is comparable to the giant meat-eaters, like T-Rex. But the creature's bird-like beak suggests it may have foraged on plants. "We don't know what kind of food it ate," said Xu.
The creature was unearthed by accident.
Two years ago, Xu was participating in a documentary film about one of his earlier dinosaur finds. Poking around a hillside in the Erlian Basin of the Gobi desert -- near the "dinosaur city" of Erenhot, famed for fossils since the 19th century -- Xu grubbed up a large femur to show a Japanese film crew how a paleontologist's work is done. It turned out to belong to a species unknown to science.
The find marked the 25th dinosaur species find credited to Xu, an extraordinary record.
The region where Gigantoraptor lived is today desert, but 70 million years ago it was a floodplain containing numerous ponds and thickets, cut by a broad river. It was great country for dinosaurs, said Xu: "Duckbilled dinosaurs, primitive tyrannosaurs, some ankylosaurs, and a kind of small titanosaurian sauropod -- that's what we know of" inhabiting the same area.
Xu said the size of the new species is a puzzle.
"But being big has advantages," he said. "You can get food that may be unavailable to smaller animals, and you don't have as many predators to eat you."
Gigantoraptor's days on earth were numbered. Most dinosaurs met their doom during a mysterious mass extinction at the end of the Cretaceous, about 65 million years ago.
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