Comparative analysis of vestibular ecomorphology in birds

• DOI: 10.1111/joa.12726
• Publication Date: 2017-11-21T00:05:15Z
• Authors: Roger B. J. Benson; Ethan Starmer‐Jones; Roger A. Close; Stig A. Walsh
• Keywords: Allometry; Morphometrics; Ecomorphology; Arboreal locomotion; Crania

The bony labyrinth of vertebrates houses the semicircular canals. These sense rotational accelerations head and play an essential role in gaze stabilisation during locomotion. sizes shapes canals have hypothesised relationships to agility locomotory modes many groups, including birds, a burgeoning palaeontological literature seeks make ecological interpretations from morphology extinct species. Rigorous tests form-function for vestibular system are required support these interpretations. We test hypothesis that lengths, streamlines angles between related body size, wing kinematics flying style birds. To do this, we applied geometric morphometrics multivariate phylogenetic comparative methods dataset 64 three-dimensional reconstructions endosseous obtained using micro-computed tomography scanning bird crania. A strong relationship centroid size indicates larger birds longer compared with their evolutionary relatives. Wing manoeuvrability (and quantified brachial index) explain small additional portion variance size. also find evidence allometric shape change indicating major aspects avian determined by spatial constraints. braincase accommodates large brain, eye other tetrapods. Negative allometry structures means restriction space within is intense This may our observation planes deviate more strongly orthogonality than those mammals, especially agile, gliding mammals. Furthermore, little or kinematics. Overall, results suggest topological problem fitting long into spatially constrained important determining specifics agility. Our tentatively indicate link visual acuity proportional among suggests labyrinths tetrapods result generally high acuities, not directly ability fly. close dinosaurian relatives allow broad inferences about flight vision, but so far provide few specific insights detailed