||Geology of the Mesozoic Era
Biotic Events of the Mesozoic Era
The Mesozoic Era, commonly called the Age of Reptiles or Age of Dinosaurs, spans the interval of Earth history from 250 million years ago to 65 million years ago. Both the beginning and end of the Mesozoic Era are marked by mass extinction events. The Permian-Triassic extinction event represents the Phanerozoic's most significant, with well over 90% of all species becoming extinct after this succession of catastrophes. The Cretaceous-Tertiary (K-T), at the end of the Cretaceous, saw the end of dinosaurs. Another mass extinction has been recognized at the end of the Triassic Period. This extinction affected many amphibian and reptile groups on land as well as in reefs.