Actually it is not a Nature paper, although I found it in the latest issue of
Nature, in the section of Research Highlights. Enjoy.
Acoustics: Nostril navigation
Phys. Rev. E 76, 051902 (2007)
The sonar squeak of a bat is governed by the shape of its nose, according to
physicists at Shandong University in Jinan, China.
Using X-ray tomography of the face of Rhinolophus rouxi (pictured), a type of
horseshoe bat, the researchers created a three-dimensional model of the
structures around its nostrils, known the noseleaf. Qiao Zhuang and Rolf Müller
programmed sonar waves to propagate through their model, noting where the waves
resonated inside the nose and what shape the waves formed when they left it.
Low-frequency waves bounced off structures that shaped them into a wide beam.
Meanwhile, high-frequency waves resonated in a separate part of the noseleaf
that focused the sonar signal. This could explain why switching frequency seems
to help horseshoe bats shift from general navigation to homing in on prey.
XIAO, Jianqiang, Ph.D.
Research Associate
Psychology Department
Rutgers University
152 Frelinghuysen Road
Piscataway, NJ 08854
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