Dinosaurs appeared in the Upper Triassic, about 230 million years ago. The earliest date of a dinosaur fossil is that of "Eoraptor" and "Herrerasaurus" from the Argentine, and "Saturnalia" from Brazil, 237 to 228 million years ago. By the early Jurassic they were the top land vertebrates, and dominated most environments on land. They continued until the sudden K/T extinction event 66 million years ago.