Triassic

The Triassic was the first geological period of the Mesozoic Era. It lasted from 252.2 to 201.3 million years ago.

Geography
During the Triassic, all the modern continents were joined together in a single supercontinent called Pangaea, and surrounded by the ocean of Panthalassa. Pangaea was already starting to break up during the Triassic, but not to a point where the landmasses actually separated. This first rift started to move modern-day Morocco and New Jersey apart, which would later expand and form the Atlantic Ocean.

Climate
The climate of the Triassic was generally hot and dry, though there were a few tropical regions around the equator. There is no evidence of glaciation at the poles during this time; rather, the climate in this part of the world was mild and temperate.

Flora
The main types of plant during the Triassic included cycads, horsetails, and ginkgo trees. In the southern hemisphere, Glossopteris was the dominant tree during the Early Triassic.

Fauna
The Permian-Triassic extinction devastated all forms of life, and ecosystems around the world took a long time to reestablish themselves. Among other things, the first ammonites, frogs, turtles, plesiosaurs, ichthyosaurs, crocodylians, pterosaurs, dinosaurs (such as Nyasasaurus, Eoraptor, and Herrerasaurus), and true mammals evolved during the Triassic.

Extinction
The Triassic ended with a mass extinction, the Triassic-Jurassic extinction event. Although it affected the whole planet, it most severely affected the oceans, as roughly half of the marine genera went extinct. On land, several types of reptiles that were dominant during the Permian and Early Triassic went extinct, leaving the dinosaurs to become the dominant form of land animal during the Jurassic. The cause of this extinction is not known with certainty.