Fig. 6. Particle acceleration audiograms of all tested species of elasmobranchs. Values for the nurse shark Ginglymostoma cirratum and yellow stingray Urobatis jamaicensis (Casper and Mann, 2006), lemon shark Negaprion brevirostris (Banner, 1967) and horn shark Heterodontus francisci monopole (Kelly and Nelson, 1975) were modified to compare to the particle acceleration data obtained in the dipole experiment. These four species were all tested with a monopole sound stimulus. The nurse shark and yellow stingray audiograms were obtained with auditory evoked potentials in terms of particle acceleration. The lemon shark and horn shark were obtained using classical conditioning methods with measurements in terms of particle displacement, which was converted to particle accelerations in this figure.