Meeting Abstract
Suction feeding is one of the most common modes of feeding in aquatic vertebrates, representing an exceptionally successful strategy for capturing prey. Suction feeding has been well studied in ray-finned fishes, but has seen less study in other taxa. Suction feeding in an elasmobranch species, white-spotted bamboo sharks, has shown noticeable functional differences from actinopterygians including posterior to anterior peak in pressure, and a decrease, rather than increase, in mediolateral width of the buccal cavity during suction. Kinematic data for jaw elements during feeding was quantified using XROMM. Long-axis rotation of the lower jaw during feeding was detected in three bamboo shark individuals. This rotation coincides with depression of the hyoid following peak gape and maximum jaw protrusion. This timing coincides with previously reported delays in the peak pressure gradient during feeding in bamboo sharks and may aid in generating suction, while the buccal cavity is compressed, by increasing total volume. Changes in marker to marker distances within the lower jaw indicate possible deformation of the posterior ventral region during feeding. Models of stress and strain during feeding typically incorporate forces perpendicular to the long axis of the lower jaw; however, this study demonstrates torsion as a potential source of stress and strain in the jaws during suction feeding, and therefore is important to modeling biomechanics as well as in functional morphological studies of the lower jaw.
