Fig. 5From: Origin of the propatagium in non-avian dinosaursThe āintermediateā and avian-state morphotypes. A Deinonychus antirrhopus representing the āintermediateā morphotype. The propatagium was present, while the wrist could extend toward the radial side in a grasping movement. B Sapeornis chaoyangensis with the avian interlocking wing-folding systemBack to article page