We know more about what dinosaurs looked like than many of our own fossil relatives. Even though excavations have turned up feathers, skin impressions and other clues about what the reptiles looked like, paleontologists have only found a handful of fossils that depict our protomammal cousins (technically called synapsids), as well as when classic mammal features like fur first evolved. A stunning cache of fossils found in South Africa has changed that, revealing what a pig-like herbivore named Lystrosaurus may have actually looked like.