Presents a concise study of the Megatherium, a giant prehistoric sloth originally believed to have inhabited parts of North, Central, and South America.
Provides a description of the prehistoric mammals known as mammoths and mastodons, which are relatives of the elephant family. Discusses their physical characteristics and geographic range, what scientists believe about their daily life, and some fossil finds.
Describes the physical characteristics, movements, diet, defenses, life cycle, and modern relatives of the prehistoric glyptodont, a large land mammal with a hard shell and armored tail.
Provides a description of the troodon, a dinosaur species that lived from about 73 million to 65 million years ago, discusses the history of troodon discovery and study, explains what scientists have learned from a nest of troodon eggs found in 1993, and speculates about the extinction of the dinosaur.
Provides a description of the spinosaurus, a dinosaur species that lived from about 100 million to 93 million years ago, discusses the history of spinosaurus and study, and examines the quest to find additional spinosaurus fossils.
Provides a description of the psittacosaurus, a dinosaur species that lived from about 120 million to 98 million years ago, discusses the history of psittacosaurus discovery and study, and speculates on what life was like for the psittacosaurus during the Cretaceous period.
Provides a description of the megalosaurus, a dinosaur species that lived from about 185 million to 160 million years ago, discusses the history of megalosaurus discovery and study, and explains how scientists can tell the difference between the fossils of various dinosaurs.