The biomechanics and energetics of locomotion in sea turtles: understanding the influence of load carrying on performance

海龟拥有脊椎动物中最独特的身体结构（1）。海龟出现在2.2亿年前的化石记录中。在脊椎动物中，海龟的独特之处在于，它们的整个身体都被封闭在由甲壳和腹甲组成的坚硬的骨质壳中，以保护免受捕食者的侵害。它们的壳似乎限制了它们的生活;然而，海龟栖息在一系列水生和陆生栖息地，许多物种有效地在两者之间移动（2，3）。我们将整合生物学，生物力学和生理学技术，在生物体到细胞水平上整理三种海龟物种的能量学数据（4）。我们选择了海龟，因为它们对不同负载的专业化程度不同（5），以提供广泛的范围，使我们能够更好地了解海龟的运动性能，在不断变化的环境中的权衡以及限制对其在盒子中生活的影响。对海龟的研究将为未来研究功能多样性、适应和进化提供重要模型。水和空气代表了生物体必须生存和移动的流体介质，这些环境之间的物理差异（密度，粘度，重力负荷）可能对生物体（如海龟）的适应和表现产生重要影响，这些生物体通常在水生和陆地环境之间穿梭。这些陆地生物群落之间的基质也存在关键差异。我们将确定如何承重影响的差异，在生物体水平上的运输和运动生物力学的代谢成本，并调查使用肌肉骨骼计算模型的适应，最终生理约束运动性能的海龟在环境变化的背景下。

Turtles have the most distinctive body plans of vertebrates (1). Turtles appear in the fossil record over 220 million years ago. Turtles are unique among vertebrates in that their whole body is enclosed within a rigid bony shell, composed of the carapace and plastron, that protects from predators. Their shells would appear to constrain their lives; however, turtles inhabit a range of both aquatic and terrestrial habitats and many species effectively move between both (2,3). We will integrate biological, biomechanical and physiological techniques to collate energetics data across three turtle species at the organismal down to the cellular level (4). We have selected sea turtles as they vary in their degree of specialisation to different loads(5) to provide a broad range that will allow us to better understand turtle locomotor performance, the trade-offs in changing environments and the impact of constraints on their life in a box. Studying turtles will provide an important model for future research on functional diversity, adaptation and evolution. Water and air represent the fluid media in which organism must survive and move and the physical disparities (density, viscosity, gravitational load) between these environments can have important consequences for adaptation and performance of organisms like turtles that routinely transverse between aquatic and terrestrial environments. There are key differences in substrate between these terrestrial biomes as well. We will determine how load bearing influences differences in the metabolic cost of transport and locomotor biomechanics at the organismal level and investigate using musculoskeletal computational models the adaptations that ultimately physiologically constrain locomotor performance in sea turtles in the context of environmental change.