Temperature: 16 °C
Atmospheric oxygen: 23%
The Permian is the last period of the Paleozoic era. It ended with the largest mass extinction in Earth’s history. The world at the time was dominated by two continents known as Pangaea and Siberia, surrounded by a global ocean called Panthalassa. Vast deserts covered Western Pangea during the Permian, as reptiles spread across the face of the supercontinent.