Читать книгу The Handy Dinosaur Answer Book - Patricia Barnes-Svarney - Страница 115

Based on the characteristics of its skeleton—a blend of archosaur and dinosaur features—scientists believe the Herrerasaurus ischigualastensis was an early dinosaur. Initially, scientists new this 10-to 18-foot (3-to 6-meter) carnivorous reptile had a skull and foot similar to other archosaurs such as the Euparkeria. Based only on this evidence, it was impossible to determine if the Herrerasaurus was truly a dinosaur. But using the modern cladistic test, the Herrerasaurus skeleton shows all but a few of the characteristics that define dinosaurs. In particular, Herrerasaurus lacks bone in the center of the hip socket, a key characteristic that defines this reptile as a true dinosaur—and one of the earliest known.