Experimental tests have shown that hammerhead sharks can detect magnetic fields. In one such test, 100 turns of wire were wrappe
d around a 7. 0-m-diameter cylindrical shark tank. A magnetic field was created inside the tank when this coil of wire carried a current of 1. 5 a. Sharks trained by getting a food reward when the field was present would later unambiguously respond when the field was turned on.
