title: Kinematic constituents of the extreme head turn of Strix aluco estimated by means of CT-scanning.
abstract: To analyze extreme sideways turn of the head in owls, a total fresh specimen of Strix aluco was frozen in respective posture and CT-scanned. The maximum turn to one side was found to be 360°, provided that the head is drawn into the shoulders. 160° of this full turn are ensured by the neck axial rotation (this includes ~90° twist of the head relative to epistropheus and, posterior to it, less than 15° per every cervical joint), and the rest 200° are ensured by combination of dorsal and lateral flexion. The 15° limit is overcome in five joints in respect of dorsiflexion, and in six joints in respect of lateral flexion. So large a degree of lateral mobility is unusual among birds, and is appreciated as a crucial adaptation to extreme head turning.
authors.affiliation: Biological Faculty of the Moscow State University, Moscow, 119992, Russia. cat2809@yandex.ru.
authors.forename: E E
authors.initials: EE
authors.lastname: Grytsyshina
authors.affiliation: Biological Faculty of the Moscow State University, Moscow, 119992, Russia.
authors.forename: A N
authors.initials: AN
authors.lastname: Kuznetsov
authors.affiliation: Biological Faculty of the Moscow State University, Moscow, 119992, Russia.|Institute of ecology and evolution of the Russian Academy of Sciences, Moscow, 119071, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Panyutina
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D006257:Head / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D020305:Strigiformes / Q000502:physiology*; D014057:Tomography, X-Ray Computed