Noseleaf pit in Egyptian slit-faced bat as a doubly curved reflector
Institute of Acoustics, Chinese Academy of Sciences - Beijing 100190, China
2 School of Science, Shandong Jianzhu University - Jinan 250101, China
3 School of Physics, Shandong University - Jinan 250100, China
Accepted: 4 January 2012
Noseleaves in slit-faced bats have been hypothesized to affect the sonar beam. Using numerical methods, we show that the pit in the noseleaf of an Egyptian slit-faced bat has an effect on focusing the acoustic near field as well as shaping the radiation patterns and hence enhancing the directionality. The underlying physical mechanism suggested by the properties of the effect is that the pit acts as a doubly curved reflector. Thanks to the pit the beam shape is overall directional and more selectively widened at the high end of the biosonar frequency range to improve spatial coverage and detectability of targets.
PACS: 43.80.+p – Bioacoustics / 43.80.Ka – Sound production by animals: mechanisms, characteristics, populations, biosonar
© EPLA, 2012