Meeting Abstract
To capture prey by suction, fishes generate a high velocity flow of water entering the mouth and exiting at the back of the head. Although the hydrodynamics associated with suction feeding is prominent to catch food successfully, difficult optical access to the buccal cavity makes it still poorly understood. Here, we used the technique of X‐ray particle tracking, which we optimized to quantify intra-oral flow dynamics in three dimensions. This method requires the use of at least two X‐ray sources and radio-opaque particles of densities close to that of the fluid medium. We specifically designed small, approximately neutrally buoyant radio-opaque particles composed of 1.4 mm diameter polystyrene foam spheres with an insert of an X-ray absorbing metal marker. Two individuals of Carp (Cyprinus carpio) were implanted with 0.35 mm diameter radio-opaque markers on the upper jaw, lower jaw, hyoid, suspensorium, branchial arches, opercula, skull and pectoral girdle, in order to link the quantified water motions with skeletal kinematics, using XROMM methods. Fishes were filmed during capturing and intra-oral manipulation of food and surrounding flow tracer particles. This analysis allowed us to obtain a more complete view on the 3D kinematics of both the animal‘s cranial system and intra-oral water during feeding.
