The Permian is a geologic period and system characterized among land vertebrates by the diversification of the early amniotes into the ancestral groups of the mammals, turtles, lepidosaurs and archosaurs. The Permian Period follows the Carboniferous and extends from 299.0 ± 0.8 to 251.0 ± 0.4 Mya (million years before the present). It is the last period of the Paleozoic Era and famous for its ending epoch event, the largest mass extinction known to science. The Permian Period was named after the Perm Krai in Russia by Scottish geologist Roderick Murchison in 1841. The term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian system" after the ancient kingdom of Permia, and not after the then small town of Perm, as usually assumed; see "Origin of the Permian" Image:Sauerstoffgehalt-1000mj.svg Image:Phanerozoic Carbon Dioxide.png Image:All palaeotemps.png Haq, B. U.; Schutter, SR (2008).