Feeding mechanism of Epibulus insidiator (Labridae; Teleostei): Evolution of a novel functional system
Feeding mechanism of Epibulus insidiator (Labridae; Teleostei): Evolution of a novel functional system
复制标题
Epibulus insidiator（Labridae；Teleostei）的摄食机制：新型功能系统的进化
作者：
M. Westneat;P. Wainwright
在鱼类中，隐石鳗的摄食机制是独特的，它的下颚突出程度是有史以来最高的（头长的65%）。作为一个案例研究，在新的功能系统的进化的颌骨机制在埃皮布勒斯的功能形态进行了分析。进食机制似乎是由非特异性肌肉活动模式和输入力驱动的，联合收割机与急剧变化的骨和韧带形态相结合，产生极端的下颌前突。主要的骨骼学特征是方骨、骨间骨、前颌骨和下颌骨的延长。腓骨有一个独特的犁骨间韧带和扩大的下颌骨间韧带和前上颌骨间韧带。鳃盖骨、上颌骨和脑颅的大部分结构保持原始的唇状。在上颚的许多颅肌也保留了原始的结构条件，包括提鳃盖肌、外轴肌、胸骨舌骨肌和下颌内收肌。在上颚部保留了广泛的鲈形骨吸食模式，即同时出现颅顶抬高、张口和下颌前突，随后是舌骨压低。肌电图和高速电影摄影表明，进食期间的肌肉活动模式以及鳃盖旋转和颅骨抬高的运动学运动产生了原始的力和运动输入模式。极端的颌骨前突是从这个原始的输入模式，由几个派生的运动模式修改的骨骼和韧带。骨间骨、方骨和上颌骨旋转约100度，将下颌推到突出位置。在结构和功能组织的多个级别上分析原始和衍生字符可以得出有关设计级别的结论，在该级别上发生了变化以产生功能新颖性。
The feeding mechanism of Epibulus insidiator is unique among fishes, exhibiting the highest degree of jaw protrusion ever described (65% of head length). The functional morphology of the jaw mechanism in Epibulus is analyzed as a case study in the evolution of novel functional systems. The feeding mechanism appears to be driven by unspecialized muscle activity patterns and input forces, that combine with drastically changed bone and ligament morphology to produce extreme jaw protrusion. The primary derived osteological features are the form of the quadrate, interopercle, and elongate premaxilla and lower jaw. Epibulus has a unique vomero‐interopercular ligament and enlarged interoperculo‐mandibular and premaxilla‐maxilla ligaments. The structures of the opercle, maxilla, and much of the neurocranium retain a primitive labrid condition. Many cranial muscles in Epibulus also retain a primitive structural condition, including the levator operculi, expaxialis, sternohyoideus, and adductor mandibulae. The generalized perciform suction feeding pattern of simultaneous peak cranial elevation, gape, and jaw protrusion followed by hyoid depression is retained in Epibulus. Electromyography and high‐speed cinematography indicate that patterns of muscle activity during feeding and the kinematic movements of opercular rotation and cranial elevation produce a primitive pattern of force and motion input. Extreme jaw protrusion is produced from this primitive input pattern by several derived kinematic patterns of modified bones and ligaments. The interopercle, quadrate, and maxilla rotate through angles of about 100 degrees, pushing the lower jaw into a protruded position. Analysis of primitive and derived characters at multiple levels of structural and functional organization allows conclusions about the level of design at which change has occurred to produce functional novelties.