Why hipposiderid biosonar is worth studying

Abstract

Although the genus Hipposideros contains a diverse set of more than 70 species of echolocating bats, the biosonar system of this group has received far less attention than that of the related horseshoe bats (family Rhinolophidae) which share the same basic cf-fm biosonar. Only a relatively small number of field observations can be found in the literature and even fewer laboratory studies on hipposiderids have been reported. The Shandong University—Virginia Tech International Laboratory has been working with two of the larger hipposiderid species, the great roundleaf bat (Hipposideros armiger) and Pratt's roundleaf bat (Hipposideros pratti) and has conducted biosonar as well as flight experiments with individuals from both species. It was observed that the bats from both species have highly dynamic biosonar systems that employ large non-rigid noseleaf motions as well as large rigid and non-rigid motions of the pinnae. The motions seen in the hipposiderids appear to be relatively larger and more frequent than those in the greater horseshoe bats with which similar experiments were conducted. In addition, the hipposiderids bats tested were found to be maneuverable fliers that should make an excellent model system for the integration of dynamic sonar with a highly capable flight system.