BEIJING -- A fossil hailed as an important find for the theory that birds evolved from dinosaurs is really a composite of fossils from different creatures, a Chinese scientist says.
Xu Xing, an eminent paleontologist in Beijing, said he has found fossils that prove the fossilized turkey-size creature unveiled last year may not be the evolutionary link some thought it was.Xu's claim has forced paleontology circles, which greeted the find with some fanfare, to take a second look. And the controversy has highlighted the pitfalls of international research projects involving fossils that are smuggled out of China and sold overseas.
Scientists have other evidence that birds evolved from dinosaurs, and Xu's finding doesn't overturn the theory.
The National Geographic Society convened a press conference in October to announce the discovery of the dinosaur, dubbed Archaeoraptor liaoningensis, which lived 120 million to 140 million years ago.
Unlike feathered dinosaurs discovered earlier, the Archaeoraptor showed evidence that it could fly, they said.
The Archaeoraptor fossil, however, included specimens that had been smuggled out of China and whose origins are therefore questioned.
Now National Geographic magazine plans to publish a note in its March issue saying CT scans of the fossil appeared to confirm Xu's observations and had "revealed anomalies" in the reconstruction, said National Geographic Society spokeswoman Barbara Moffet. She added that more information was needed.
Xu contends the Archaeoraptor is a combination of two fossils: one of the body and head of a birdlike creature and the other of the tail of a different dinosaur. He said he has found another fossil, in a private collection in China, that contains the mirror image of the supposed tail of the Archaeoraptor.
Fossils often break in two when the rocks containing them are split in excavation.
"This is a completely new dinosaur. It's nothing like the Archaeoraptor," Xu, of China's Institute of Vertebrate Paleontology and Paleoanthropology, said in an interview.
Paleontologist Stephen Czerkas, who bought the Archaeoraptor fossil at a gem and mineral sale in Utah, said Xu may be right.
"No one has been able to actually compare the two fossils side-by-side. Research is still ongoing. But that is what we are all tending to believe."
Still, Czerkas said the Archaeoraptor, even without its tail, remained a very important find.
"It's still totally one of a kind, first time anyone has seen anything like this before," said Czerkas, who with his wife, Sylvia, runs the Dinosaur Museum in Blanding, Utah.
He said Xu's dinosaur, a dromaeosaur that could not fly, was also "very exciting."
"We've never had a tail with feathers," Czerkas said. "We're getting new information about the dromaeosaur we've never had before."
Xu said he could not disclose further details about his find until he finished a research article for Nature magazine to be published later this year. He has invited U.S. scientists to visit Beijing to examine his find.
The fossils were unearthed in western Liaoning province, a barren, semi-desert region about 260 miles northeast of Beijing that is a treasure trove for paleontologists.
The region, which in prehistoric times was a humid lake area with abundant vegetation and wildlife, has yielded spectacular fossils of ancient birds and of dinosaurs with birdlike characteristics that some scientists say are evidence that birds evolved from dinosaurs.
But as with other antiquities, China lacks the means to protect such treasures. Theft is such a problem that in another fossil-rich area, in southern Guangdong province, authorities offer rewards of up to $12,000 for tips on poachers, according to the Xinhua News Agency.
"Lots of specimens have been smuggled out for commercial purposes," Xu said. "For science, this is a disaster.
"When pieces are stolen and smuggled out, sometimes blocks of fossils are matched together mistakenly. That can be a big mistake, and it misleads the public."
Czerkas said he planned to return the Archaeoraptor fossil, which was illegally taken out of China, within several months.
"It is one of their natural treasures. Ultimately, it comes down to doing the right thing," he said.