DEEP TIME, ONE DISCOVERY AT A TIME
A world millions of years in the making
Dinosaurs were part of a long, changing story. A prehistoric world was never one single moment.
THE EARLIER CHAPTERS
Before dinosaurs
Ancient seas supported life long before dinosaurs evolved. Cameroceras belongs to an Ordovician story; Dunkleosteus lived in the Devonian. Dimetrodon’s Permian world came later, but still before the first dinosaurs.
Discover other lineages →TRIASSIC
The first dinosaur chapters
Early dinosaurs appeared during the Triassic, alongside many other reptile groups. The earliest members differed substantially from the enormous creatures familiar from later periods.
Explore the Triassic →JURASSIC
A world of changing giants
The Jurassic included long-necked sauropods, stegosaurs and a great variety of theropods. Allosaurus and Stegosaurus belonged to this chapter. They lived long before the Late Cretaceous world of Tyrannosaurus.
Explore the Jurassic →CRETACEOUS
Familiar faces, new landscapes
Flowering plants spread and dinosaur communities changed. Triceratops and Tyrannosaurus appeared late in this period. Mosasaurs swam in the seas, while pterosaurs flew above them; neither group was a dinosaur.
Explore the Cretaceous →ABOUT 66 MILLION YEARS AGO — AND AFTER
A surviving dinosaur lineage
The end-Cretaceous extinction removed the non-avian dinosaurs and many other groups. Birds survived. Today’s birds are living dinosaurs, connecting the prehistoric story with the world around us.
International Chronostratigraphic Chart ↗