Tree biloba". This is considered to be a living fossil because it is virtually unchanged from the fossilised specimens found in Triassic deposits. During the Mesozoic (245 to 66 million years ago) the conifers flourished and became adapted to live in all the major terrestrial habitats. Subsequently, the tree forms of flowering plants evolved during the Cretaceous period. These began to displace the conifers during the Tertiary era (66 to 2 million years ago) when forests covered the globe. When the climate cooled 1.5 million years ago and the first of four ice ages occurred, the forests retreated as the ice
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