Dinosaur egg

A dinosaur egg is a giant egg that dinosaurs hatch from. 
If dropped the egg will break and vanish. When placed near a heat source, like a heater, the egg will hatch. The baby dinosaur is a full-sized compsognathus, and it is hostile.
Birds will protect dinosaur eggs. In Scribblenauts Remix the Dragon Egg and Dinosaur Egg are different things. Dragon Eggs do not hatch.