May 3, 2024
This Fossil Friday, sail into the weekend with this vintage photo of Edaphosaurus, a sail-backed herbivore that lived some 280 million years ago during the Permian Period. While Edaphosaurus may resemble a big lizard, it wasn’t a reptile: It’s actually more closely related to mammals! The key feature that tells us about this relationship? The synapsid openings behind each of Edaphosaurus’ eye sockets—a trait found in all mammals but absent in reptiles. You can find Edaphosaurus in the Hall of Primitive Mammals. Plan your visit!
Photo: Image no. ptc-847 © AMNH Library