Nothing except the dinosaur's eight-foot-long arms, tipped in three huge claws, and a handful of other bone fragments had ever been found.

But at the annual Society of Vertebrate Paleontology conference held in Los Angeles last week, Korea Institute of Geoscience and Mineral Resources paleontologist Yuong-Nam Lee presented a wealth of new fossils that make Deinocheirus stranger than anyone had previously imagined. (See also "Bizarre Dinosaurs.")

The finding points to a curious environment for ancient Mongolia during the Age of Dinosaurs, a time when the region was apparently filled with oversize plant-eating dinosaurs and stalked by knife-toothed tyrannosaurs.