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IS THERE AN OPTION FOR A PNEUMATIC STABILIZATION OF SAUROPOD
NECKS? – AN EXPERIMENTAL AND ANATOMICAL APPROACH
Daniela Schwarz-Wings and Eberhard Frey ABSTRACT
The reconstructed distribution of the major pneumatic diverticula systems in the sauropod neck might hint towards pneumatic stabilization or operation of the long neck, which was investigated considering anatomical and mechanical aspects of soft-tissue reconstructions in the neck of sauropods as well as experimental data. The mechanical role of pneumatic bodies in a generalized segmented beam of Styrodur™ blocks, which was stabilized by air-filled tube-like balloons, was tested with an experiment. A support effect was evident already with one ventral pneumatic system. Adding further pneumatic systems increased the load capacity of the beam. Furthermore, the presence or absence of proximal intersegmental blocks, pressure changes within the balloons, proximal fixation of the balloons or their fixation at each segment respectively, and the degree of segmentation of the pneumatic systems changed the efficiency of support.
In the necks of sauropods, pneumatic support would hinge on the specific reconstruction of the pneumatic diverticula, sufficiently high pressures and a possibility for regulating pressure of the pneumatic system. Only if pneumatic diverticula would extend beyond their bony boundaries at the vertebral surface, and if one or more pressure regulating mechanisms were present, would a support effect be an option. Because none of these factors can be reliably reconstructed on an osteological basis, the hypothesis of pneumatic neck support in sauropods remains hypothetical. However, the combination of pneumatic support with other bracing mechanisms in the sauropod neck results in a consistent constructional morphological model for a pneu aided neck support in sauropods.
Daniela Schwarz-Wings, Naturhistorisches Museum Basel, Augustinergasse 2, 4001 Basel Switzerland
Current address: Museum für Naturkunde der Humboldt-Universität Berlin, Invalidenstraße 43, 10115 Berlin, Germany.
Eberhard "Dino" Frey, Staatliches Museum für Naturkunde Karlsruhe, Erbprinzenstr. 13, D-76133 Karlsruhe, Germany
Key words: sauropod; pneumaticity; air sacs; vertebra, cervical; neck support; Styrodur™ model
PE Article Number: 11.3.17A
Copyright: Palaeontological Association October 2008
Submission: 28 January 2008. Acceptance: 13 October 2008
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