for National Geographic News
The principal part of a famously fabricated dinosaur fossil is an ancient fish-eating bird, scientists report.
The Archaeoraptor fossil was introduced in 1999 and hailed as the missing evolutionary link between carnivorous dinosaurs and modern birds. It was fairly quickly exposed as bogus, a composite containing the head and body of a primitive bird and the tail and hind limbs of a dromaeosaur dinosaur, glued together by a Chinese farmer. [See sidebar]
Initial CT scans suggested that the fossil might have been made up of anywhere from two to five specimens of two or more species. Chinese and American scientists now report that the fabricated fossil is made up of two species.
The tail and hind limbs were identified in 2000 as belonging to a Microraptor zhaoianus, a small, bipedal, meat-eating dinosaur with some bird-like features.
Scientists in the November 21 issue of the journal Nature report that the avian parts of the false dinosaur-bird fossil are from one specimen, a fish-eating bird known as Yanornis martini.
Yanornis martini was first identified by Zhou Zhonghe and Zhang Fucheng, paleontologists at the Institute of Vertebrate Paleontology and Paleoanthropology, in 2001. The bird lived in the Early Cretaceous, around 120 to 110 million years ago. Yanornis had advanced features approaching those of modern birds, and strong flying abilities.
Birds and Dinosaurs
Prior to their appearance in the false Archaeoraptor fossil, both Microraptor andYanornis were unknown species.
"Yanornis is an important new species, and is going to receive more attention in the future," said Julia Clarke, a paleontologist at the American Museum of Natural History in New York and one of the study's co-authors.
"Every new species coming out of China brings us closer to understanding the anatomical changes that occurred on the evolutionary path between raptor-dinosaurs and living birds," she said. "And that was a really long road."
The fossils come from the Liaoning Province of China, where thousands of flying and non-flying dinosaur fossils have been uncovered. The site has provided compelling evidence confirming the bird-dinosaur link.
"The idea that birds evolved from dinosaurs is supported by a tremendous amount of evidence," said Kevin Padian, curator of the University of California, Berkeley, Museum of Paleontology, and a professor of integrative biology.
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