Cranial pneumatization and auditory perceptions of the oviraptorid dinosaur <Emphasis Type="Italic">Conchoraptor gracilis</Emphasis> (Theropoda,Maniraptora) from the Late Cretaceous of Mongolia |
| |
Authors: | Martin Kundrát Ji?í Janá?ek |
| |
Institution: | (1) Redpath Museum-Biology Department, McGill University, 859 Sherbrooke Street West, Montreal, Quebec, H3A 2K6, Canada;(2) Institute of Physiology, The Academy of Sciences of the Czech Republic, Vídeňská 1083, 142-20 Prague 4, Czech Republic |
| |
Abstract: | The distribution of air-filled structures in the craniofacial and neurocranial bones of the oviraptorid ZPAL MgD-I/95, discovered
at the Hermiin Tsav locality, Mongolia, is restored. Based on the complete obliteration of most of the cranial sutures, the
specimen is identified as an adult individual of Conchoraptor gracilis Barsbold 1986. Except for the orbitosphenoids and epipterygoids, the preserved bones of the neurocranium are hollow. Three
types of tympanic recess are present in Conchoraptor, a characteristic shared with troodontids, dromaeosaurids, and avian theropods. The contralateral middle ear cavities are
interconnected by the supraencephalic pathway that passes through the dorsal tympanic recesses, the posterodorsal prootic
sinuses and the parietal sinus. The spatial arrangements of the middle ear cavity and a derived neurocranial pneumatic system
in Conchoraptor indicate enhancements of acoustic perception in the lower-frequency registers and of auditory directionality. We further
speculate that this improvement of binaural hearing could be explained as an adaptation required for accurate detection of
prey and/or predators under conditions of low illumination. The other potentially pneumatic structures of the Conchoraptor cranium include (1) recessus-like irregularities on the dorsal surface of the nasal and frontal bones (a putative oviraptorid
synapomorphy; pos); (2) a subotic recess; (3) a sub-condylar recess; and (4) a posterior condylar recess (pos).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. |
| |
Keywords: | Theropoda Oviraptorosauria Conchoraptor Neurocranium Pneumatic sinus Acoustic perceptions Binaural hearing Directionality |
本文献已被 PubMed SpringerLink 等数据库收录! |
|