Demystify world's largest bird-like dinosaurUPDATED: 15:37, June 19, 2007
After two years of study, scholars of the Chinese Academy of Sciences and Bureau of State Land and Resources of Inner Mongolia Autonomous Region, recently announced that the skeletal remains of a gigantic, surprisingly bird-like dinosaur, Gigantoraptor erlianensis, found in the Erlian Basin in Inner Mongolia and newly classified as a species and genus, is the largest of its kind known to the world. The remains were on display at the news conference held in the Beijing Olympic Media Center on June 13th.
The fossil of the Gigantoraptor erlianensis has greatly enriched human knowledge of the evolutionary process from dinosaurs to birds. Experts called it "the largest feathered, beaked, yet flightless and toothless bird-like dinosaur."
Judging from the sketch, the gigantic bird-like dinosaur is particularly strange in appearance, with parrot-like beak, a long feathered forelimb, and chicken-like feet; walking upright. Experts said that this dinosaur is extremely large. It stands up five meters high and its body length exceeds eight meters. The dinosaur weighs more than 1,400 kilograms, and can almost compete in body size with the historically famous Tyrannosaurus Rex.
Experts believe that the Gigantoraptor erlianensis share similar features with birds. Telling from the fossil, scientists can know more about the evolutionary process from dinosaurs to birds.
Usually, bird-like dinosaurs were small in size, experts say, and most weighed between less than one kilogram and several kilograms several kilograms. However, the Gigantoraptor erlianensis weighed several hundred times more than other bird-like dinosaurs; thereby laying its claim on being "the world's largest bird-like dinosaur." The fossils of the leg bones of Gigantoraptor erlianensis on display at the news conference are larger than a bull's or camel's leg bones. It is difficult to believe they are related to birds.
Xu Xing, professor at the Chinese Academy of Sciences' Institute of Vertebrate Paleontology & Paleonanthropology, found a strange fossil during a routine inspection. Different from any other fossil, this one is extremely large.
Xu discovered the fossil by chance in April 2005, when experts from the Chinese Academy of Sciences and Bureau of State Land and Resources of Inner Mongolia Autonomous Region were making a routine inspection within the Erlian Basin. At that time, Japan's NHK television station was shooting a dinosaur fossils program on site. Together with other staff, Xu was demonstrating how dinosaur fossils were cleaned. Xu started with a fossil partly buried under earth and used his brush to clean it. However, after this fossil was completely exposed, Xu was surprised to discover that the fossil seemed to be completely different from any fossils found in the past. Thus, a large-scale exploration began. After more than two years of study and repair, the fossil has been finally confirmed to be part of a giant dinosaur fossil.
Why they waited two years before announcing the discovery? Xu said that it was because of Gigantoraptor erlianensis' large size. Usually Oviraptors are very small. This is like a very common rat, but with the size of a pig. Everyone will go crazy when they see this. So, "we need to conduct sufficient research and experiments before we can make sure."
Scholars once believed that this fossil belongs in the Tyrannosaurus category because of its large size. However, studies ultimately affirmed that it is a Gigantoraptor erlianensis, a transition type of dinosaur that survived egg robbery.
The weight of the Gigantoraptor erlianensis is about 300 times that of its relative, the Caudipteryx. Scientists speculate that the Gigantoraptor erlianensis might also have had feathers.
Moreover, experts also discovered the extraordinary proportions of the hind legs of the Gigantoraptor erlianensis. Generally, larger dinosaurs have stronger limbs and shorter lower legs. The Gigantoraptor erlianensis, however, had slim hind legs and slender lower legs, indicating that it had a stronger ability to run than other dinosaurs.
Bone analysis indicates that this dinosaur lived to be eleven years of age, just after entering adulthood. It is speculated that a giant, adult dinosaur weighs more than 1,400 kilograms. Scientists also used CT scanning technology to observe its spine, and found out that it has a spongy internal structure in its vertebra-similar to a number of large herbivorous sauropod dinosaurs. This might have been a way to reduce the weight of the dinosaur.
So far there are still two unanswered questions. First, the toothless giant dinosaur has a big beak like other birds and the Oviraptors. Was the beak for cutting small plants or preying on small animals? Or, was it for crushing eggshells? In addition, scientists still have no idea about the function of peculiar holes on the vertebra.
By People's Daily Online
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