Archaeopteryx of Avialae (defined by the authors as the most inclusive clade containing "Passer domesticus", but not "Dromaeosaurus albertensis" or "Troodon formosus"). "Archaeopteryx" was found to form a grade at the base of Avialae with "Xiaotingia", "Anchiornis", and "Aurornis". Compared to "Archaeopteryx", "Xiaotingia" was found to be more closely related to extant birds, while both "Anchiornis" and "Aurornis" were found to be more distantly so. Archaeopteryx Archaeopteryx (), meaning "old wing" (sometimes referred to by its German name ("original bird" or "first bird")), is a genus of bird-like dinosaurs that is transitional between non-avian feathered dinosaurs and modern birds. The name
Dinosaur vision Dinosaur vision Dinosaur vision was, in general, better than the vision of most other reptiles, although vision varied between dinosaur species. Coelurosaurs, for example, had good stereoscopic or binocular vision, whereas large carnosaurs had poor binocular vision, comparable to that of modern alligators. Most carnosaurs, including "Carcharodontosaurus" and "Allosaurus", did not have very good binocular vision, comparable to modern alligators. They possessed binocular vision which was restricted to a region only 20° wide, which is understandable, as they hunted mostly large and slow prey. Their keenest sense was probably smell. Deinonychosaurs, like "Stenonychosaurus" and "Velociraptor", had better binocular vision than