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Potential for intracranial movements in pterosaurs
1Department of Paleontology, Eötvös Loránd University, Budapest, Hungary. prondvaie@gmail.com
Anatomical Record (Hoboken, N.J. : 2007)
|April 2, 2011
Summary
Pterosaur skulls were rigid and lacked cranial kinesis, despite some features suggesting movement. These traits may have mechanical or developmental roles, not indicating true skull flexibility in pterosaurs.
Area of Science:
- Paleontology
- Comparative Anatomy
- Biomechanics
Background:
- Pterosaurs, extinct flying reptiles, exhibit diverse skull morphologies.
- Cranial kinesis, the ability of skull bones to move, is common in vertebrates but its presence in pterosaurs is debated.
Purpose of the Study:
- To assess the potential for cranial kinesis in pterosaurs based on anatomical and phylogenetic evidence.
- To investigate the functional significance of skull features suggestive of intracranial movement.
Main Methods:
- Comparative anatomical analysis of pterosaur skulls.
- Morphological examination of otic and basal joints.
- Phylogenetic considerations of skull ossification trends.
Main Results:
- Skeletally mature derived pterodactyloids had rigid, akinetic skulls.
- Immature individuals and basal pterosaurs showed features like streptostyly, suggesting potential kinesis.
- A crucial requirement for cranial kinesis, permissive kinematic linkages, was absent in all pterosaurs.
Conclusions:
- All pterosaurs possessed akinetic skulls, lacking the necessary anatomical linkages for cranial kinesis.
- Apparent indicators of intracranial movement likely served mechanical or ontogenetic functions.
- These features might represent a remnant from kinetic-skulled diapsid ancestors.
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