Expedition finds mass grave of young dinosaurs

Apparently, reckless adolescent behavior has been around a lot longer a lot longer than people realize. As a matter of fact, it's been around a lot longer than people.

University of Chicago paleontologist Paul Sereno of Naperville says that's one of the lessons of some recent fossil finds in the desert regions of China.

Sereno says a large group of adolescent and preadolescent dinosaurs died en masse 90 million years ago when they ran into a mudhole, sinking to their doom.

Many of the 25 individuals recovered were so perfectly preserved that their last meals could be identified.

Sereno is scheduled to give a formal report Monday in the provincial capital of Inner Mongolia on the findings of the joint U.S.-Chinese expedition that found the fossils.