Abstract: The echolocation system of 24 Leaf-nosed bats, Rhinolophus rouxi was studied by behavioral testing the obstacle-avoidance. Among them, 20 bats were used to test their obstacle ability by the pinna back on the animal's head. The rest were used for contrast test.The data obtained shows that ( 1 ). The percent of the obstacle avoidance in bats with the change of one pinna position is always significantly lower (P<0.01) than those in normal ones, and (2). The percent by all bats obtained from the change of both pinna position is significantly lower (P<0.01) than those bats with change of one pinna position. The mean percentages are 86.64±8.29%(normal bats), 71.37±6.59%(one pinna change) and 60.29 ± 7.56% (both pinna change), respectively.It is shown that the ability of obstacle avoidance of bats changes with different pinna orientations. It appears that the pinna orientation of bats plays an important role during echolocation.

Key words: Microchiroptera, Echolocation, Obstacle avoidance, Pinna orientation, Directional sensitivity

摘要： 实验在24只鲁氏菊头蝠(Rhinolophus rouxi)中进行。使用障碍回避测定法,观察了蝙蝠耳廓方位对其回避障碍能力的影响。发现动物耳廓呈自然状态时,回避障碍成功率最高,平均为86.64±8.29%。当将一侧耳廓向头部后方翻转后,其障碍回避的成功率降为71.37±6.59%,平均下降了15.27%。差异非常显著。当将双侧耳廓同时翻向头部后方,动物回避障碍能力进一步下降。较改变单侧耳廓方位的回避障碍成功率又平均下降11.08%,差异显著。实验结果提示,食虫蝙蝠的耳廓方位,在其回声定位中起着重要作用。文中还从听觉神经生理学方面,对论了耳廓方位影响回声定位行为的可能机理。

关键词: 小翼手亚目, 回声定位, 障碍回避, 耳廓方位, 方向灵敏性