The Permian is a geologic period and system which extends from 298.9 ± 0.2 to 252.2 ± 0.5 (Million years ago). It is the last period of the Paleozoic Era, following the Carboniferous Period and preceding the Triassic Period of the Mesozoic Era. It was first introduced in 1841 by geologist Sir Roderick Murchison, and is named after the ancient kingdom of Permia. The Permian witnessed the diversification of the early amniotes into the ancestral groups of the mammals, turtles, lepidosaurs and archosaurs. The world at the time was dominated by a single supercontinent known as Pangaea, surrounded by a global ocean called Panthalassa. The extensive rainforests of the Carboniferous had disappeared, leaving behind vast regions of arid desert within the continental interior. Reptiles, who could better cope with these dryer conditions, rose to dominance in lieu of their amphibian ancestors. The Permian Period (along with the Paleozoic Era) ended with the largest mass extinction in Earth's history, in which nearly 90% of marine species and 70% of terrestrial species died out. It would take well into the Triassic for life to recover from this catastrophe.