Rhynchocephalians were a successful, globally distributed group of diapsid reptiles that thrived in the Mesozoic. Multiple species of Clevosaurus existed worldwide in the Late Triassic and Early Jurassic, characterized by shearing bladelike teeth perhaps functionally analogous to the carnassial teeth of mammals. Morphometric analysis shows that the dentary morphospace of clevosaurs differs significantly from that of other rhynchocephalians. Five Clevosaurus species occupied islands in the Bristol Channel archipelago of the UK, but generally not those occupied by mammaliaforms, suggesting dietary character displacement. Identifying the diet of such ancient, small tetrapods has been difficult. To identify the nature of their feeding mechanics and ecology, we apply finite element analysis to two near complete three-dimensional skulls of the species Clevosaurus hudsoni and Clevosaurus cambrica to estimate bite force, resistance to bending and torsion and the distribution of stresses in the jaws during biting. Both species had bite forces and tooth pressures sufficient to break apart chitin indicating that, like early Mesozoic mammaliaforms, clevosaurs could feed on tough-shelled beetles and possibly small vertebrates. In addition, the mechanical advantage of the jaws falls within the range of early mammaliaforms, so though we cannot demonstrate niche partitioning between members of the two clades, it raises the prospect that they may have been functionally

中文翻译：

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两种链状龙颌骨的生物力学特性及喉头类牙齿形态空间的再分析

Rhynchocephalians 是一个成功的、分布于全球的双胞胎爬行动物，它们在中生代繁衍生息。在晚三叠世和早侏罗世，世界范围内存在多种 Clevosaurus，其特征是剪切刀片状的牙齿，可能在功能上类似于哺乳动物的肉体牙齿。形态测量分析表明，钩龙类的齿状形态空间与其他钩头类的有显着差异。五种 Clevosaurus 物种占据了英国布里斯托尔海峡群岛的岛屿，但通常没有被哺乳动物占据的岛屿，这表明饮食特征发生了位移。确定这种古老的小型四足动物的饮食一直很困难。为了确定它们的进食机制和生态的性质，我们对 Clevosaurus hudsoni 和 Clevosaurus cambrica 物种的两个近乎完整的 3D 头骨应用有限元分析，以估计咬合力、抗弯曲和抗扭力以及咬合过程中颌部应力的分布。这两个物种的咬合力和牙齿压力足以分解几丁质，这表明，像早期中生代哺乳动物一样，叉龙可以吃硬壳甲虫和可能的小型脊椎动物。此外，颌骨的机械优势属于早期哺乳动物的范围，因此虽然我们无法证明两个进化枝的成员之间的生态位划分，但它提出了它们可能在功能上的前景 抗弯曲和扭转能力以及咬合过程中下颌应力分布。这两个物种的咬合力和牙齿压力足以分解几丁质，这表明，像早期中生代哺乳动物一样，叉龙可以以坚硬的甲虫和可能的小型脊椎动物为食。此外，颌骨的机械优势属于早期哺乳动物的范围，因此虽然我们无法证明两个进化枝的成员之间的生态位划分，但它提出了它们可能在功能上的前景 抗弯曲和扭转能力以及咬合过程中下颌应力分布。这两个物种的咬合力和牙齿压力足以分解几丁质，这表明，像早期中生代哺乳动物一样，叉龙可以吃硬壳甲虫和可能的小型脊椎动物。此外，颌骨的机械优势属于早期哺乳动物的范围，因此虽然我们无法证明两个进化枝的成员之间的生态位划分，但它提出了它们可能在功能上的前景