Fossil Friday Dimetrodon. Dimetrodon is often mistaken as a dinosaur or as a contemporary of dinosaurs in popular culture, but it went extinct around 40 million years before the appearance of the first dinosaur.
Generally reptile-like in appearance and physiology, Dimetrodon is nevertheless more closely related to mammals than it is to any living reptilian group
© The Field Museum, GEO80667.
Fossil Preparation of specimen, Dimetrodon (UC 1) from Walker Collection University of Chicago. In 1947 they transferred their entire collection of vertebrate fossils including UC 1 to Field Museum.