World of Dinosaurs/Dinosaurs Through Time

Here we show a rough schematic of the TIMETREE of dinosaurs as they proliferated throughout the Mesozoic.

Fossils from Triassic rocks show few dinosaurs, and these animals are relatively small and basal in their anatomy. Dinosaur fossils are much more common, and show greater animal diversity, in Jurassic rocks. Finally, the most famous and culturally iconic dinosaurs (Tyrannosaurus, Triceratops, etc.) are known from fossils in Cretaceous rocks.