Scientists piece together the 'dino-bird' fossil fraud

An extinct species of fish-eating bird has been identified by palaeontologists as the other half of a fraudulent fossil that was once hailed as the "missing link" between dinosaurs and birds.

Scientists have proved conclusively that the fossil known as Archaeoraptor, which has the tail of a dinosaur and the feathered wings of a bird, was in fact two or more fossils stuck together with strong glue.

The fossil came to prominence in 1999 when the magazine National Geographic published an account of its discovery and how it had been scientifically validated as a fossil that many palaeontologists would die for.

Archaeoraptor, however, soon went from "a true missing link in the complex chain that connects dinosaurs to birds" to "Piltdown turkey", a reference to the most famous forgery in palaeontology.

A team led by Zhonghe Zhou of China's Institute of Vertebrate Palaeontology and Palaeanthropology in Beijing has closed the book on the controversy by identifying the extinct species of bird that was used to make the fossilised chimera.

In a study published in the journal Nature, Dr Zhou says that Archaeoraptor is actually the front half of an ancient fish-eating bird called Yanornis stuck together with the tail of a small carnivorous dinosaur belonging to a group known as the dromaeosaurs.

"The principal portion of the Archaeoraptor forgery, which we conclude was constructed from two different specimens belonging to two different species, is therefore representative of a fish-eating bird," the scientists conclude in Nature.

Archaeoraptor has been smuggled out of China where it was "discovered" by one of the many farmers who have been unearthing remarkable dinosaur fossils in the north-eastern province of Liaoning.

Dr Zhou said the temptation to add a longer tail would have been difficult to resist. "This specimen was presumably assembled by a Chinese farmer who wished to make it a more complete looking fossil, which could be sold for a higher price," he said.

The specimen ended up in America where it was bought by a private collector for $80,000 (£51,000). It appeared to be the perfect example of a creature that was half dinosaur, half bird and it became an icon for the evolutionary transition between the two.

Soon after the accounts were published, though, the other half of the slab containing the fossil was discovered at the same site in China.

"This new specimen preserving the tail and other bones clearly proved what others had suspected; that Archaeoraptor is indeed a composite specimen," Dr Zhou said.

The tail of the fossil was identified as belonging to Microraptor, one of the smallest flesh-eating dinosaurs, which possibly lived in trees. Now the other half is identified as Yanornis martini, which lived at about the same time, some 115 million years ago.

"With the publication of this paper, the identity of the infamous 'Archaeoraptor' specimen is finally clear. In other words we can now safely say that it comprises the tail of the smallest non-flying dinosaur Microraptor and a moderate-sized bird called Yanornis," Dr Zhou said.

The findings, he said, did not discredit other fossil finds that clearly showed a link between dinosaurs and modern birds. "Not at all. For instance, earlier this year we described a very primitive bird called Jeholornis with a dromaeosaur-like tail and a lot of characters suggesting flying capability," Dr Zhou said.

"In spite of the Archaeoraptor story, there are a lot evidence supporting the dino-bird link, which we can still trust," he said.

Nevertheless, the fraud has been exploited by religious fundamentalists keen to undermine any evidence of Darwinism.

Dr Zhou added: "What we learn most from this story is that illegal and non-scientific collecting and smuggling of fossils is really hurting palaeontology. We can never be too careful in scientific study."

Fossil flops

The most famous fossil fraud is that of Piltdown man, perpetrated by Charles Dawson, an amateur archaeologist. He claimed in 1912 to have a skull proving the "missing link" between apes and humans. Radiocarbon dating in 1953 showed that the skull was that of a human about 600 years old, while the jawbone came from an orangutan.

Religious fanatics used the fraud to question human evolution, even though other fossils have shown a clear line of descent from ape-like human ancestors.

But scientists have had to admit that DNA from fossilised dinosaur bones was in fact their own genetic material, which contaminated their equipment.

Steve Connor