Liem Karel F
Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138.
J Morphol. 1978 Dec;158(3):323-360. doi: 10.1002/jmor.1051580305.
Among piscivorous cichlids consistent differences have been recorded between ambush and pursuit hunters with respect to electromyographic, kinematic, pressure and behavioral profiles during prey capture by high speed inertial suction. Piscivorous cichlids possess a repertoire of at least two patterns of prey capture, each of which is characterized by an extreme regularity of the kinematic, pressure, electromyographic and behavioral profiles. The nature and locomotory behavior of the prey, visually analyzed by the predator during the prestrike stalk, determine which of the two preprogrammed patterns is recruited. Agile and elusive prey invariably will elicit a preprogrammed motor output (stereotyped motor pattern) that produces the greatest suction velocities in both ambush and pursuit hunters. The greater the kinematic and suction velocities, the greater the overlap of the firing sequences of antagonistic muscle complexes. The opercular and branchiostegal apparati function as an exceedingly effective anti-backwash device, damping potential fluid oscillations within the oropharynx. Mastication occurs by triphasic movements and actions of muscles of the upper and lower pharyngeal jaws in both ambush and pursuit hunters. The lower pharyngeal jaw is acted upon by a force couple of which the fourth levator externus on one hand and the pharyngocleithralis externus and pharyngohyoideus on the other hand are the antagonistic components. Furthermore, the lower pharyngeal jaw is suspended by a muscular sling, the tension of which can be modified continuously. It is postulated that the switch from insectivorous to piscivorous feeding regimes (and perhaps vice versa) is accomplished by very minor structural and functional modifications, because the modulatory multiplicity and total range of repertories of the feeding machinery of the two trophic groups overlap significantly. Piscivorous cichlids may not have arisen by orthoselection in gradually-changing lineages, but represent the differential success of subsets from a random pool of speciation events. Adaptive features identified as characteristic for piscivory could have evolved in multiple and independent lineages at a punctuational mode and tempo.
在食鱼丽鱼科鱼类中，伏击型猎手和追捕型猎手在通过高速惯性吸食捕获猎物时，其肌电图、运动学、压力和行为特征方面存在一致差异。食鱼丽鱼科鱼类具有至少两种猎物捕获模式，每种模式的特点是运动学、压力、肌电图和行为特征具有极高的规律性。在攻击前的潜行过程中，捕食者通过视觉分析猎物的性质和运动行为，从而决定采用两种预先设定模式中的哪一种。敏捷且难以捉摸的猎物总是会引发一种预先设定的运动输出（刻板运动模式），这种模式在伏击型和追捕型猎手中都会产生最大的吸食速度。运动速度和吸食速度越大，拮抗肌复合体的放电序列重叠程度就越大。鳃盖和鳃条骨装置起到了极其有效的防逆流装置的作用，可抑制口咽腔内潜在的流体振荡。伏击型和追捕型猎手的咀嚼都是通过上、下咽颌肌肉的三相运动和动作来完成的。下咽颌受到一个力偶的作用，其中一方面是第四块外提肌，另一方面是外咽锁骨肌和咽舌骨肌，它们是拮抗成分。此外，下咽颌由一个肌肉吊带悬吊，其张力可以不断调节。据推测，从食虫性摄食方式转变为食鱼性摄食方式（也许反之亦然）是通过非常微小的结构和功能改变实现的，因为这两个营养组的摄食机制的调节多样性和全部范围有很大重叠。食鱼丽鱼科鱼类可能并非在逐渐变化的谱系中通过定向选择产生，而是代表了物种形成事件随机库中不同子集的不同成功情况。被确定为食鱼特征的适应性特征可能是以间断的模式和节奏在多个独立谱系中进化而来的。
