Triassic Triassic The Triassic () is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.9 million years ago (Mya), to the beginning of the Jurassic Period Mya. The Triassic is the first period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it would take well into the middle of this period for life to recover its former diversity. Therapsids and archosaurs were the chief terrestrial
The Magic School Bus In the Time of the Dinosaurs periods (Triassic, Jurassic, and Cretaceous) were seen in the book; only the book focuses with all of the time periods. This is because it was due to time constraints; time constraints in order for the episode to be up to 30 minutes (30 minutes like all episodes in the TV series). In this episode, the kids visit Ms. Frizzle's old friend, Dr. Carmina Skeledon at a dinosaur dig, as opposed to Jeff in the book. Dr. Skeledon lets Arnold see a fossilized dinosaur egg that Ms. Frizzle finds as the kids are leaving, and he still has it when they