The Dimetrodon lived during the early Permian Period, and while it looks reptilian, it’s not related to dinosaurs. It’s more closely related to mammals, although not technically mammalian ...

The preservation of footprints, plant fossils, and environmental imprints allows scientists to reconstruct a vivid picture of the Permian period and how early life thrived under changing conditions.

About 250 million years ago, at the end of the Permian period, something killed some 90 percent of the planet's species. Less than 5 percent of the animal species in the seas survived. On land ...