Archaeopteryx suggested that "Archaeopteryx" was a dinosaur that was no more closely related to birds than were other dinosaur groups. Kurzanov (1987) suggested that "Avimimus" was more likely to be the ancestor of all birds than "Archaeopteryx". Barsbold (1983) and Zweers and Van den Berge (1997) noted that many maniraptoran lineages are extremely birdlike, and they suggested that different groups of birds may have descended from different dinosaur ancestors. The discovery of the closely related "Xiaotingia" in 2011 led to new phylogenetic analyses that suggested that "Archaeopteryx" is a deinonychosaur rather than an avialan, and therefore, not a "bird" under most
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