The end-Permian mass extinction (EPME) occurred about 250 million years ago and represents the Earth’s most catastrophic extinction event. Up to 96% of marine species and 70% of terrestrial vertebrate species went extinct, opening up habitats for the evolution of dinosaurs and mammals. A new study, being presented at the 77th Annual Society of Vertebrate Paleontology meeting in Calgary, Alberta, compares the recovery of land-dwelling vertebrates from different localities in the southern portion of the super continent Pangaea. Presenter Brandon Peecook explains, “By studying the different ecosystems that assembled after the largest mass extinction in Earth history we can get a sense of the ecological and geographic context in which the earliest members of important lineages (like mammals and dinosaurs) first appeared.”