How sauropod dinosaurs were able to withstand the forces associated with their immense size represents one of the most challenging biomechanical scenarios in the evolution of terrestrial tetrapods, but also one lacking robust biomechanical testing. Here, we use finite element analyses to quantify the biomechanical effects of foot skeletal postures with and without the presence of a soft tissue pad in sauropodomorphs. We find that none of the models can maintain bone stresses that fall within optimal bone safety factors in the absence of a soft tissue pad. Our findings suggest that a soft tissue pad in sauropods would have reduced bone stresses by combining the mechanical advantages of a functionally plantigrade foot with the plesiomorphic skeletally digitigrade saurischian condition. The acquisition of a developed soft tissue pad by the Late Triassic–Early Jurassic may represent one of the key adaptations for the evolution of gigantism that has become emblematic of these dinosaurs.

中文翻译：

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通过踏板垫的进化，软化蜥脚类恐龙的巨人症

蜥脚类恐龙如何能够承受与其巨大体型相关的力量，这是陆地四足动物进化过程中最具挑战性的生物力学场景之一，但也是缺乏稳健生物力学测试的场景之一。在这里，我们使用有限元分析来量化脚骨骼姿势的生物力学效应，无论是否存在蜥脚类恐龙软组织垫。我们发现，在没有软组织垫的情况下，没有一个模型可以将骨应力保持在最佳骨安全系数范围内。我们的研究结果表明，蜥脚类动物中的软组织垫可以通过将功能性跖行足的机械优势与拟形骨骼指代蜥臀目条件相结合来减少骨应力。