Avimimus

Phylogeny: Dinosauria > Saurischia > Theropoda > Neotheropoda > Tetanurae > Avetheropoda > Coelurosauria > Maniraptora > Pennaraptora > Oviraptorosauria > Avimimidae

Overview: Growing to around one or two meters in length, Avimimus was a smaller dinosaur, but a fairly important genus nonetheless. If they had the chance to observe an actual living specimen, a majority of people would easily mistake it for a true bird. When it was described in 1981, many saw it as being extremely closely related to birds, possibly even more so than the famed Archaeopteryx. Indeed, for that time, Avimimus had a remarkably high amount of distinctly avian features when it’s compared to other non-avian dinosaurs. Some even suggested the animal may’ve been capable of at least weak or clumsy flight. Most scientists today think this was unlikely to have been the case. With its long legs, Avimimus was probably more suited for a terrestrial lifestyle. Even so, with such a birdlike anatomy, it’s little wonder it was described under the name of “bird mimic”.

Modern studies usually find Avimimus to have been more basal than Archaeopteryx, so nowhere near as close to true birds as previously thought. It was still a derived theropod, however, being a member of the Maniraptora, most likely belonging to the clade Oviraptorosauria. Of course, this made it related to the famous Oviraptor, but Avimimus was much less derived, usually classified as a basal oviraptorosaur. It was more derived than Incisivosaurus or Caudipteryx, however. Similar to basically all other maniraptorans, Avimimus would’ve possessed feathers. It’s often cited as a toothless dinosaur, like its more derived kin, but some specimens have been found with limited, tiny teeth. It was probably omnivorous. It’s primarily known from Mongolia’s Nemegt Formation, so it may’ve coexisted with Therizinosaurus, Deinocheirus, Tarbosaurus, and Saurolophus.