John Noble Wilford
September 26, 2006
Full Article on The New York Times online
A graduate student in paleontology was standing on the downtown subway platform at the American Museum of Natural History stop. He idly inspected the bronze cast on the wall of one of the museum’s dinosaurs.
The student, Sterling J. Nesbitt, was surprised to see what looked like crocodile bones that had presumably been the dinosaur’s last feast. This set in motion a re-examination of two specimens on display in the museum’s Hall of Dinosaurs, and wiped clean a dinosaur’s reputation that had been besmirched by suspicions of cannibalism.
Museum paleontologists found that the exhibited predatory dinosaur, Coelophysis bauri, had in fact not eaten one of its own. “Our research shows that the evidence for cannibalism in Coelophysis is nonexistent,” Mr. Nesbitt said in an interview, “and the evidence for cannibalism in other dinosaurs is quite thin.”
In one of the two suspected specimens, the bones of the dinosaur’s last meal, lying inside the skeleton where its stomach would have been, were not those of a juvenile Coelophysis or any other dinosaur. The review showed the bones were of a small crocodile. “The femur was the key,” Mr. Nesbitt said. “I knew this wasn’t a dinosaur that had been eaten.”
The re-examination of the second fossil specimen disputed the assumption that the bones in the stomach area of a Coelophysis were of a cannibalized young dinosaur. The scientists said the bones were outside the dinosaur’s ribcage, and from an animal perhaps too large to have been eaten whole.
The verdict of not-guilty of cannibalism was delivered last week in the journal Biology Letters of the Royal Society of London. The lead author is Mr. Nesbitt, a doctoral student at Columbia and the museum.The two Coelophysis specimens were excavated in New Mexico in 1947 by a dinosaur-hunting party from the museum. The bones that appeared to lie within the dinosaurs’ bodies led Edwin H. Colbert, a museum paleontologist in those days, to assume these animals had been cannibals.
Mark A. Norell, the museum’s curator of paleontology and a co-author of the report, said, the new research was a reminder that it is not always necessary to go all the way to the Gobi Desert to learn something new about dinosaurs. For his part, Mr. Nesbitt said: “It’s pretty lucky. It was an example of serendipity.” And, he added, it helped to be alert while waiting for the subway train.
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