Morphology and the location of the ampullae in respect to the shark’s head plays a large role in the function of the ampullae. Using the location of the ampullae, sharks can use their electrosensory system to aid in capturing prey, locating predators, as well as in social behaviors. In sharks, the ampullae are split into three different planes. These planar clusters differ in head location, sensitivity, and field detection direction. The three planes are the superficial ophthalmic group (SO), buccal group (BUC), and the mandibluar group (MAN). Together, these three groups of ampullae help sharks detect electrical fields from all directions (Tricas, 2001).
The SO cluster is positioned midway between the eye and the tip of the shark’s snout. This cluster has the longest canals that form a small group of pores just lateral to the tip of the snout. Because of the location of the SO cluster on the shark’s head, it is believed that these pores play an important role in shark attacks. Many sharks, such as the great white, prefer to attack prey that is resting on the surface. This way, sharks can use the element of surprise to their advantage. Just before a shark attacks, its eyes roll back into the socket to protect from possible injury, leaving the shark blind momentarily before the attack. Because the SO clusters lie in the shark’s field of vision, scientists believe that sharks use these clusters to guide them in the final seconds before attack, during the attack, in pursuit of the prey after an attack, and to detect changes in the prey, such as bleeding (Tricas, 2001).
The BUC cluster is located near the ventral surface of the snout, dorsal to the upper jaw. The BUC cluster has the second longest canals, and they project in a turnstile-like pattern. The BUC cluster aids in location prey in front of and beneath the shark (Tricas, 2001).
The MAN cluster is the smallest cluster in sharks. In the great white shark (C. carcharias), it only contains thirteen canals. The MAN cluster is located beneath the lower jaw near the corner of the mouth. The MAN cluster aids the BUC cluster in locating prey below the shark (Tricas, 2001).
|STRUCTURE OF THE AMPULLAE|
|THE FUNCTION OF THE GEL IN THE AMPULLAE|
|THE COMPASS SENSE|
|NEURO-ECOLOGY AND PERIPHERAL MORPHOLOGY|
|ELECTRICAL SHARK DETERRENTS|