Prehistoric Life Prehistoric Secrets in Stone The Earliest Fossils The Silurian Reef Trilobites Fish The Coal Forests Early Reptiles and Amphibians Sea Reptiles Flying Reptiles The Teeming Seas Hunting Dinosaurs Biggest Dinosaurs Two-Footed Plant Eaters Plated and Armoured Dinosaurs Horned Dinosaurs The Mammal Age Dawns Grassland Mammals The Ice Age	Choose a Page:Insects in Amber*Original Bones*CarbonizationPetrified WoodMoldCastTrace FossilSecrets in Stone Original Bones The hard parts of an animal may be preserved. For example, a bone of a mammal has been found in Ice Age tar pits in Los Angeles.   Previous: Back Book: Prehistoric Life Section: Prehistoric Chapter: Secrets in Stone