Evolution of the pectoral girdle and forelimbs of frogs and toads: from ontogeny to biomechanical mechanisms

尽管青蛙和蟾蜍的形态相对保守(无尾两栖纲：无尾两栖动物)，但在这一支系中进化出了大量不同的运动行为。众所周知，颅后骨骼的大多数部分都适应特定的运动行为。然而，肌肉结构的适应性和肌肉骨骼系统中潜在的生物力学仍然知之甚少。前肢和胸带虽然对运动很重要，但与骨盆带和后肢相比，很少受到关注。因此，我们打算分析实现不同前肢和胸带配置的生物力学原理与运动行为的关系，最终目的是推断和解释前肢和胸带肌肉骨骼系统的进化。鉴于肌肉单位的识别和命名上的不一致，我们将首先研究肌肉个体发育，以表明在整个无尾两栖动物系统发育以及无尾两栖动物和尾目之间有良好支持的肌肉同源性。功能分析将使用多体动力学模拟和有限元分析进行。

Despite the otherwise comparably conserved morphology of frogs and toads (Lissamphibia: Anura), a large diversity of locomotor behaviors has evolved within this clade. It is well-known that most parts of the post-cranial skeleton are adapted to specific locomotor behaviors. Yet, adaptations in muscle configurations and the underlying biomechanics in the musculoskeletal system remain poorly understood. The forelimbs and pectoral girdle, although of high importance for locomotion, have gained little attention compared to the pelvic girdle and hindlimbs. We therefore intend to analyze the biomechanical principles underlying the realization of different forelimb and pectoral girdle configurations in relation to locomotor behaviors with the ultimate goal of inferring and explaining the evolution of the musculoskeletal system of the forelimbs and the pectoral girdle. Given inconsistencies in the identification and naming of muscle units, we will first study muscle ontogeny to suggest well-supported muscle homologies across the entire anuran phylogeny and between the Anura and Caudata. Functional analyses will be performed using multibody dynamics simulations and finite element analyses.