Apatosaurus opponent of Marsh and his taxa, labeled the "Apatosaurus" mount of the American Museum of Natural History "Brontosaurus". Because of this decision the name "Brontosaurus" was commonly used outside of scientific literature for what Riggs considered "Apatosaurus", and the museum's popularity meant that "Brontosaurus" became one of the best known dinosaurs, even though it was invalid throughout nearly all of the 20th and early 21st centuries. It was not until 1909 that an "Apatosaurus" skull was found during the first expedition, led by Earl Douglass, to what would become known as the Carnegie Quarry at Dinosaur National Monument. The skull
Jurassic for the large herbivorous dinosaurs known as the sauropods—"Camarasaurus", "Apatosaurus", "Diplodocus", "Brachiosaurus", and many others—that roamed the land late in the period; their foraging grounds were either the prairies of ferns, palm-like cycads and bennettitales, or the higher coniferous growth, according to their adaptations. The smaller Ornithischian herbivore dinosaurs, like stegosaurs and small ornithopods were less predominant, but played important roles. They were preyed upon by large theropods, such as "Ceratosaurus", "Megalosaurus", "Torvosaurus" and "Allosaurus". All these belong to the 'lizard hipped' or saurischian branch of the dinosaurs. During the Late Jurassic, the first avialans, like "Archaeopteryx", evolved from small