News Release

Montana researcher co-authors Science article on Niger dinosaurs

Peer-Reviewed Publication

Montana State University

BOZEMAN, MONT--A Bozeman, Mont., researcher who's studied dinosaur fossils in Morocco, Argentina and Niger co-authored a paper that appears in the Nov. 12, 1999 issue of Science.

David Varricchio, a research associate at the Museum of the Rockies at Montana State University, was one of 11 scientists who contributed to the article. It is titled "Cretaceous Sauropods from the Sahara and the Uneven Rate of Skeletal Evolution Among Dinosaurs."

The article resulted from a 1997 expedition to Niger, an African country north of Nigeria. The participants found information that "provides the first quantitative assessment of rates of skeletal changes among dinosaurs," according to the Science article. "... Some lineages, such as that leading to Jobaria, remained relatively static for tens of millions of years, whereas others changed rapidly. Considerable variation in the rate of skeletal change appears to have been the norm in dinosaur evolution."

The Niger expedition was Varricchio's third in three years with Paul Sereno of the University of Chicago. Sereno led a team to Morocco in 1995 and Argentina in 1996. Varricchio's role was to interpret the geological setting and look at how the fossils were preserved.

"I was in charge of gathering data on where the fossils were and how they might have gotten there," Varricchio said. "My responsibilties included mapping the bones and skeletons within the quarries, as well as describing the sediments from which they came. This is important in the interpretation of ancient environments."

Sereno wants to understand how dinosaur bones are distributed and how the dinosaurs evolved as the continents split, Varricchio said. That curiosity led him to dinosaur beds that haven't been well-studied.

The most abundant fossils at the Niger site were Jobaria, Varricchio said. They were large dinosaurs that ate plants and inspired legends among the local residents who found their bones.

"Jobaria are very ordinary-looking," Varricchio explained. "It's exciting because it's almost too ordinary looking for the time it is in. It is kind of like a relic. It looks like it should have existed 40 million years before it did."

Other Niger fossils came from slightly younger bone beds. The most common one there, the Nigersaurus, had a muzzle that was strangely different from other dinosaurs. It was squared off instead of pointed.

"The new fossils provide a framework for understanding the history of African sauropods during the Cretaceous Period," the Science article said.

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