NEW YORK CITY -- Fossil hunters are used to making discoveries underground, but not where Sterling Nesbitt made his--in the New York City subway system.
Nesbitt is a student in paleontology at Columbia University and the American Museum of Natural History. Not long ago, he was waiting in the subway station near the museum, idly inspecting the bronze castings of fossils that adorn the station's walls. One of the castings is of the predatory dinosaur Coelophysis (see-loh-FYE-sis) that supposedly cannibalized its young. The casting shows the bones of a juvenile Coelophysis inside the stomach of an adult Coelophysis.
Running his finger along the femur (upper leg bone) of the digested youngster, Nesbitt searched for the knob that is characteristic of dino femurs. It wasn't there!
Nesbitt persuaded the museum to let him inspect the fossil from which the casting was made. The femur knob wasn't there either. The bones inside the adult dinosaur's stomach were not those of a juvenile dinosaur, concluded Nesbitt. They were those of another reptile, perhaps a prehistoric crocodile.
Nesbitt's discovery led scientists to inspect another Coelophysis fossil, this one in New Mexico. The second fossil also shows a young Coelophysis inside the stomach of an adult Coelophysis. The scientists realized that the youngster's bones were too big to have been swallowed by an adult. The bones had simply become entangled with the bones of the adult, making it seem as if one had swallowed the other, the scientists concluded. "Coelophysis is held up as the foremost example of cannibalistic behavior in dinosaurs," says Nesbitt, "but our work suggests that isn't true."
Nesbitt may have dropped the charge of cannibalism against Coelophysis, but the dinosaur's name has not been completely cleared. Spencer Lucas, a paleontologist at the New Mexico Museum of Natural History and Science, says he has found evidence of baby Coelophysis bones in the coprolites (fossil feces) of an adult Coelophysis. The case continues.
Source Citation
"Dino cleared of cannabalism?" Current Science, a Weekly Reader publication 15 Dec. 2006: 14+. Academic OneFile. Web. 8 July 2010.
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