 However, some fossils support the version of this theory that holds that some non-flying carnivorous dinosaurs may have had flying ancestors.In particular, "Microraptor", "Pedopenna", and "Anchiornis" all have winged feet, share many features, and lie close to the base of the clade Paraves.This suggests that the ancestral paravian was a four-winged glider, and that larger Deinonychosaurs secondarily lost the ability to glide, while the bird lineage increased in aerodynamic ability as it progressed.