Jannel Andréas, Salisbury Steven W, Panagiotopoulou Olga
School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.
Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia.
Sci Adv. 2022 Aug 12;8(32):eabm8280. doi: 10.1126/sciadv.abm8280. Epub 2022 Aug 10.
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.
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，但也是一个缺乏有力生物力学测试的场景。在这里，我们使用有限元分析来量化蜥脚形亚目恐龙在有和没有软组织垫的情况下足部骨骼姿势的生物力学效应。我们发现，在没有软组织垫的情况下，没有一个模型能够维持处于最佳骨骼安全系数范围内的骨骼应力。我们的研究结果表明，蜥脚类恐龙的软组织垫通过将功能性跖行足的机械优势与原始的骨骼趾行式蜥臀目条件相结合，从而降低了骨骼应力。晚三叠世-早侏罗世发达的软组织垫的获得，可能代表了这些恐龙标志性的巨型化进化的关键适应之一。
