'Gigantoraptor' uncovered in the desert

'Gigantoraptor' uncovered in the desert
By Roger Highfield, Science Editor
13/06/2007
Tellegraph UK

'Roadrunner' dinosaur discovered
A 3000 lb "big bird" dinosaur called Gigantoraptor has got scientists into a flap.
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The remains of the gigantic, surprisingly bird-like dinosaur - the biggest toothless dinosaur ever found - have been uncovered in the Gobi desert in Inner Mongolia, China, and challenge current understanding about the origins of birds.

The find was made when Chinese scientists were being filmed by a Japanese TV crew in Erlian Basin and they thought a nearby bone was an example of a newly discovered long necked dinosaur, called a sauropod.

But as they took a closer look, under the gaze of the camera, they at first thought it came from something like Tyrannosaurus rex, but then realised that they were gazing on a remarkable dinosaur that was new to science.

The animal - which lived in the Late Cretaceous- about 85 million years ago - has surprised palaeontologists as most theories suggest that carnivorous dinosaurs got smaller as they got more bird-like.

advertisementThere is even a hint, from the patterns of growth on its remains, that this specimen was a youthful 11 year old that could in theory have lived until around the age of 18.

Because it has an unusual spongy lightweight tail and arm bones, the eight metre dinosaur, which is described today in Nature, has been classed as a new species and genus (group of species), dubbed Gigantoraptor erlianensis, and boasts a formidable ten inch beak, Dr Xing Xu told The Daily Telegraph.

This is "the biggest toothless dinosaur ever found because some dinosaurs have both a small beak and many teeth."

Dr Xu, at the Chinese Academy of Sciences, Beijing, and Prof. Lin Tan of Long Hao Institute of Geology and Paleontology, Hohhot, carried out an analysis of the skeleton they uncovered together and have grouped the fossil with a family that included the beaked, bird-like Oviraptor because of its unusually shaped jaw.

What is most striking, however, is that at 1,400-kilograms, or 3000 lb, the fossil is about 35-times heavier than other similar feathered oviraptorosaurs dinosaurs, which rarely exceeded a body mass of 40 kilograms, or around 90 pounds.

Gigantoraptor is remarkable in its gigantic size, about 300 times as heavy as primitive feathered peers already known to science, such as Caudiperyx and Protarchaeopteryx.

Previously, the largest known feathered animal was the 500-kg-heavy Stirton's Thunder Bird (Dromornis stirtoni) which lived in Australia 8-6 million years ago and was three times smaller.

The big bird-like dinosaur would have stood, at the shoulder, twice the height of a man, with feathers at least on its arm and tail, and probably grew much faster than the likes of T rex.

But, despite its great size, many features of its anatomy were more bird-like, rather than less, as would have been expected, said Dr Xu.

"Normally, when dinosaurs become large in size, they have proportionally stouter limbs and shorter lower legs than their small-sized relatives.

However, Gigantoraptor has much more slender limbs and longer lower legs than similarly-sized theropods."

Gigantoraptor's diet remains unknown, as it shows both herbivorous features, notably a small head and long neck, and carnivorous features, such as sharp claws. In one sense, the new discovery is not a surprise.

Erlian Basin has attracted palaeontologists from around the world for a long time due to the richness of its fossils.