Horseshoe bats and Old World leaf-nosed bats have two discrete types of pinna motions

Publication Type:Journal Article
Year of Publication:2017
Authors:Yin, Qiu, Yang, Müller
Journal:The Journal of the Acoustical Society of America
Volume:141
Issue:5
Pagination:3011 - 3017
Date Published:Jan-05-2017
ISSN:0001-4966
Abstract:

Horseshoe bats (Rhinolophidae) and the related Old World leaf-nosed bats (Hipposideridae) both show conspicuous pinna motions as part of their biosonar behaviors. In the current work, the kinematics of these motions in one species from each family (Rhinolophus ferrumequinum and Hipposideros armiger) has been analyzed quantitatively using three-dimensional tracking of landmarks placed on the pinna. The pinna motions that were observed in both species fell into two categories: In “rigid rotations” motions the geometry of the pinna was preserved and only its orientation in space was altered. In “open–close motions” the geometry of the pinna was changed which was evident in a change of the distances between the landmark points. A linear discriminant analysis showed that motions from both categories could be separated without any overlap in the analyzed data set. Hence, bats from both species have two separate types of pinna motions with apparently no transitions between them. The deformations associated with open–close pinna motions in Hipposideros armiger were found to be substantially larger compared to the wavelength associated with the largest pulse energy than in Rhinolophus ferrumequinum (137% vs 99%). The role of the two different motions in the biosonar behaviors of the animals remains to be determined.

URL:http://asa.scitation.org/doi/10.1121/1.4982042
DOI:10.1121/1.4982042
Short Title:The Journal of the Acoustical Society of America
BioAcoustica ID: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith