Describes plants and animals that lived during the Ordovician Period, where it falls in the geologic time scale, tectonic activity happening then, the climate and environment, and extinction events.

Provides an overview of the Mesozoic Era, its time frame, geological and tectonic activities, the climate, plants and animals, and extinction events towards the end of this era.

Looks at the geological changes, climate, and flora and fauna of the Devonian Period.

The Jurassic Period falls within the Mesozoic Era. Read about geologic events that occurred then, the climate, and the plants and animals, including the many types of dinosaurs.