The variability of inner ear orientation in saurischian dinosaurs: testing the use of semicircular canals as a reference system for comparative anatomy.

ABSTRACT: The vestibular system of the inner ear houses three semicircular canals-oriented on three nearly-orthogonal planes-that respond to angular acceleration stimuli. In recent years, the orientation of the lateral semicircular canal (LSC) has been regularly used to determine skull orientations for comparative purposes in studies of non-avian dinosaurs. Such orientations have been inferred based on fixing the LSC to a common set of coordinates (parallel to the Earth's horizon), given that the orientation to gravity of this sensory system is assumed constant among taxa. Under this assumption, the LSC is used as a baseline (a reference system) both to estimate how the animals held their heads and to describe craniofacial variation among dinosaurs. However, the available data in living birds (extan

SUBMITTER: Marugan-Lobon J 

PROVIDER: S-EPMC3740149 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature