Gigantic bird-like dinosaur stirs debate

The discovery of a new dinosaur species is stirring debate among experts.

ByABC News
February 9, 2009, 2:38 PM

BEIJING June 13, 2007 — -- The dinosaur world's latest star had a toothless beak, waved feathered arms incapable of flight, and may have hunted only plants. But if you met Gigantoraptor erlianensis in a Mongolian forest 70 million years ago, it was best to have given it a wide berth. At more than 16 feet tall and roughly 3,000 pounds, the beast could eyeball a tyrannosaur, Chinese researchers say.

The bones of what its discoverers call the world's largest birdlike dinosaur were revealed Wednesday in Beijing. The announcement came two years after the remains were dug from a mud hill near the Inner Mongolian city of Erlian in 2005.

Most theories suggest that carnivorous dinosaurs shrank as they grew more birdlike. This latest find is about 35 times heavier than other similar feathered dinosaurs, called oviraptors. "This could be the largest-ever species to have feathers," said Xu Xing, the lead scientist behind the discovery, reported in the journal Nature.

"Some experts may not believe this dinosaur had feathers, as it is so big, and we did not find traces of feathers, but from the evidence we unearthed, and all the tests we have done, we are confident in our research," Xu, 38, said in Beijing Wednesday.

Gigantoraptor erlianensis "is a very cool dinosaur, a very interesting find," agreed paleontologist Thomas Holtz, Jr., of the University of Maryland, College Park. The previous largest oviraptor was horse-sized. Most oviraptors are about the size of a child. "And this new one is the size of a tyrannosaur. I mean, whoa, that's large," Holtz said.

Yet it was not even fully grown. "It was 11 when it died, and at the growth stage of a high school graduate, so it still had some growing to do," said Xu.

The Gobi Desert area of northern China, bordering Mongolia, where Gigantoraptor erlianensis was unearthed, is a famously barren landscape today. Back in the Late Cretaceous period, however, "it was an ideal place for dinosaurs, with lakes, plenty of vegetation and a hot climate," said Tan Lin, vice director of the Longhao Geology and Paleontology Research Institute of Inner Mongolia, who co-authored the study and was present at the discovery. "In 41 years of dinosaur hunting, this is my top discovery, I was so excited," said Tan.