Turingan Ralph G, Wainwright Peter C, Hensley Dannie A
Department of Biological Science, Florida State University, 32306-3050, Tallahassec, FL, USA.
Department of Marine Sciences, University of Puerto Rico, 00681, Mayaguez, PR, USA.
Oecologia. 1995 Jun;102(3):296-304. doi: 10.1007/BF00329796.
The relationships between prey utilization and jaw biomechanics were explored in two Caribbean populations (La Parguera and Mona Island) of four trigger-fishes. The volumetric contribution of major prey types and six biomechanical features of the jaws that characterize biting strength were contrasted between populations. At Mona, Xanthichthys ringens ate 45% benthic organisms, whereas conspecifics at La Parguera fed exclusively on plankton. Balistes vetula at Mona consumed 63% soft and nonelusive invertebrates, in contrast to their La Parguera conspecifics, which consumed 62% hard prey. Differences in diet between populations were associated with differences in jaw biomechanics. Xanthichthys at Mona had jaw muscles, bones, and closing-lever ratios larger than those of fish at La Parguera, indicating a stronger bite. Balistes at Mona had 50% smaller jaw bones, muscles, and closing-lever ratios than their La Parguera conspecifics, indicating a weaker but swifter bite. Melichthys niger and Cantherhines macrocerus ate similar prey at the two locations and showed little difference in trophic anatomy. We hypothesize that the interpopulation differences in morphology are induced by the activities of feeding on different prey and enhance the feeding ability of fishes for locally dominant prey. Plasticity of the feeding mechanism may be a widespread attribute of fish feeding systems that promotes the ability of species to occupy multiple habitat types successfully.
在加勒比地区的两个地点（拉帕尔古拉和莫纳岛），对四种扳机鱼的猎物利用情况与颌骨生物力学之间的关系进行了研究。对比了两个地点主要猎物类型的体积贡献以及表征咬合力的颌骨六个生物力学特征。在莫纳岛，黄鳍扳机鱼食用45%的底栖生物，而拉帕尔古拉的同物种则仅以浮游生物为食。莫纳岛的黑背鼻鱼食用63%的软体且不具逃逸能力的无脊椎动物，相比之下，其在拉帕尔古拉的同物种则食用62%的硬壳猎物。不同地点的食性差异与颌骨生物力学差异相关。莫纳岛的黄鳍扳机鱼的颌骨肌肉、骨骼和闭合杠杆比大于拉帕尔古拉的鱼，表明咬合力更强。莫纳岛的黑背鼻鱼的颌骨骨骼、肌肉和闭合杠杆比比其在拉帕尔古拉的同物种小50%，表明咬合力较弱但速度更快。黑背鼻鱼和大鼻前孔鲷在两个地点食用相似的猎物，在营养解剖学上几乎没有差异。我们推测，形态上的种群间差异是由以不同猎物为食的活动所诱导的，并增强了鱼类对当地优势猎物的捕食能力。摄食机制的可塑性可能是鱼类摄食系统的一个普遍特征，有助于物种成功占据多种栖息地类型。
