This scene is based on fossils from the Geraldine Bonebed from the Early Permian Nocona Formation of Texas. The sail-backed synapsid Edaphosaurus boanerges munches on the horsetail relative Sphenophyllum oblongifolium. In spite of its reptilian appearance, Edaphosaurus is more closely related to mammals. Edaphosaurids were one of the first tetrapod groups to become dedicated herbivores. …