Functional anatomy and feeding biomechanics of a giant Upper Jurassic pliosaur (Reptilia: Sauropterygia) from Weymouth Bay, Dorset, UK
Functional anatomy and feeding biomechanics of a giant Upper Jurassic pliosaur (Reptilia: Sauropterygia) from Weymouth Bay, Dorset, UK
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DOI：
10.1111/joa.12200
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发表时间：
2014-08-01
影响因子：
2.4
通讯作者：
Benton, Michael J.
中科院分区：
文献类型：
--
作者：
Foffa, Davide;Cuff, Andrew R.;Benton, Michael J.
上龙是中生代海洋中最大的掠食者之一，但人们对它们的功能解剖学和摄食生物力学知之甚少。来自英国韦茅斯湾启默里阶的一种保存完好的新上龙揭示了与进食相关的颅骨适应。计算机断层扫描的数字建模可以重建颅骨和内收肌组织缺失、扭曲的区域，这表明咬合力很高。尺寸校正梁理论模型表明，与其他水生和陆生捕食者相比，鼻子在抵抗弯曲和扭转应力方面的优化很差，这表明上龙在进食过程中不会扭曲或摇晃猎物，并且通过联合骺后咬合可以更好地捕捉猎物。有限元分析确定了上颌和下颌中咬合引起的应力模式，突出了上颌前颌接触和尾部下颌联合的薄弱区域。相对较弱的头骨与能够产生强大力量的肌肉组织相结合，被解释为敏捷性、流体动力学和力量之间的权衡。在启莫里阶生态系统中，我们得出的结论是，侏罗纪晚期的上龙是食物链顶端的多面食肉动物，能够捕食长度达到自身一半的爬行动物和鱼类。
Pliosaurs were among the largest predators in Mesozoic seas, and yet their functional anatomy and feeding biomechanics are poorly understood. A new, well-preserved pliosaur from the Kimmeridgian of Weymouth Bay (UK) revealed cranial adaptations related to feeding. Digital modelling of computed tomography scans allowed reconstruction of missing, distorted regions of the skull and of the adductor musculature, which indicated high bite forces. Size-corrected beam theory modelling showed that the snout was poorly optimised against bending and torsional stresses compared with other aquatic and terrestrial predators, suggesting that pliosaurs did not twist or shake their prey during feeding and that seizing was better performed with post-symphyseal bites. Finite element analysis identified biting-induced stress patterns in both the rostrum and lower jaws, highlighting weak areas in the rostral maxillary-premaxillary contact and the caudal mandibular symphysis. A comparatively weak skull coupled with musculature that was able to produce high forces, is explained as a trade-off between agility, hydrodynamics and strength. In the Kimmeridgian ecosystem, we conclude that Late Jurassic pliosaurs were generalist predators at the top of the food chain, able to prey on reptiles and fishes up to half their own length.