March 28, 2008—A suspicious package found on a bus in Peru turned out to contain a mysterious and massive animal jawbone, officials announced on Tuesday.

Police who investigated the bus's cargo hold said they noticed the package because it had no identifying marks and was oddly heavy.

"They were worried about its weight, opened it, and found the fossil," Kleber Jimenez, a local police officer, told the Reuters news service.

Pablo de la Vera Cruz, an archaeologist at the Universidad Nacional de San Agustín de Arequipa, initially identified the 19-pound (8.6-kilogram) jawbone via police photos as perhaps belonging to a Triceratops, according to Reuters.

But Michael J. Ryan, head of vertebrate paleontology at the Cleveland Museum of Natural History, told National Geographic News that the bone is definitely not from a dinosaur.

"It's a lower jawbone, and it has two big molars in the back and that's it. That's definitely a mammalian trait." he said after seeing the above photo of the find taken at a Tuesday press conference in Arequipa.

"Also, the jaws are fused, left and right, and the massive shape and articulation mean it's definitely a mammal," he continued.

Ryan thinks the remains most likely belonged to a proboscidean, or elephant relative.

"I can't even tell if it's fossil or modern," based on the photograph, Ryan added. But, he said, "there's no way it's a Triceratops."

—Victoria Jaggard

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