Pedersen S C
School of Biological Sciences, University of Nebraska, Lincoln 68588-0548.
J Morphol. 1993 Oct;218(1):85-98. doi: 10.1002/jmor.1052180107.
This study suggests that the evolution of head posture in bats is constrained by the demands of vocalization during echolocation. Nasal-emitting microchiropteran taxa are easily identified by their characteristic rotation of the basicranium ventrally about the cervical axis, the depression of the rostrum below the basicranial axis, and by the rotation of the lateral semicircular canals so as to maintain their horizontal orientation during flight. The converse is true for oral-emitting Microchiroptera. The general form of the microchiropteran skull has been canalized along two distinct evolutionary paths, respectively, towards oral-emitting or nasal-emitting forms.
这项研究表明，蝙蝠头部姿势的进化受到回声定位过程中发声需求的限制。通过基本颅骨围绕颈椎轴腹侧的特征性旋转、吻部在基本颅骨轴下方的凹陷以及外侧半规管的旋转，可轻松识别出通过鼻腔发声的小型蝙蝠类群，以便在飞行过程中保持其水平方向。对于通过口腔发声的小型蝙蝠来说则相反。小型蝙蝠头骨的一般形态已分别沿着两条不同的进化路径被固定下来，朝着通过口腔发声或通过鼻腔发声的形式发展。
