Arboreal snake locomotion: A model system for studying effects of musculoskeletal design and environmental variation on three-dimensional movements

本项目将使用肌电图学、三维运动学和力测量来研究蛇在树上的运动作为模型系统，以更好地了解脊椎动物的轴向功能以及肌肉骨骼系统和运动控制的非常一般的特征。在复杂的三维树木环境中，狭窄和圆柱形的表面、倾斜和树枝之间的间隙提出了几个非常适合确定的要求：肌肉骨骼性能的限制和权衡，影响步态选择的近距离因素，以及感觉信息在复杂环境中改变运动输出和选择不同路线的作用。研究物种在肌肉骨骼解剖学上有相当大的差异，这对功能普遍重要，包括：肌腱与肌肉内收缩组织长度的比率，肌肉横截面积，全身长度与体重，以及骨骼关节的数量和活动度。这种解剖变异可能反映了柔韧与僵硬、强壮与虚弱、沉重与轻盈之间的权衡，所有这些通常都很重要，尤其与蛇执行不同的生态相关任务有关--主动弯曲以适应和抓住圆柱形表面，以及支撑松散地覆盖在广泛分布的树枝上的身体。一种研究物种是棕树蛇，它在关岛造成代价高昂的停电，但确定该物种无法通过的表面，并获得有关路线选择和弥补缺口的信息，应有助于管理这种破坏性的入侵物种。跨学科的合作者包括一位专门研究知觉和运动控制整合的认知科学家，以及试图降低棕树蛇经济成本的应用生物学家。该项目强调为来自不同背景的生物学家的早期职业发展提供机会，向包括网络材料在内的广大受众传播科学成果，并为K-12学生和当地社区提供以进化为重点的讲座。

This project will use electromyography, three-dimensional kinematics and force measurements to study the arboreal locomotion of snakes as a model system to better understand axial function of vertebrates and very general features of musculoskeletal systems and motor control. The narrow and cylindrical surfaces, inclines and gaps between branches in complex three-dimensional arboreal environments pose several demands well suited for determining: the limits and tradeoffs for musculoskeletal performance, proximate factors influencing gait selection, and the role of sensory information for modifying motor output and choosing different routes in complex environments. The study species have considerable variation in musculoskeletal anatomy that is universally important for function including: the ratio of tendon to contractile tissue length within muscles, the cross-sectional areas of muscle, total body length to weight, and the numbers and mobility of skeletal joints. This anatomical variation likely reflect tradeoffs between being flexible vs. stiff, strong vs. weak, and heavy vs. light, all of which are generally important as well as specifically relevant for snakes performing the different ecologically relevant tasks of actively bending to conform and grip cylindrical surfaces vs. supporting a body draped loosely over widely spaced branches. One study species is the brown tree snake, which causes costly power outages in Guam, but determining the surfaces that are impassable for this species and obtaining information on route choice and gap-bridging should facilitate managing this destructive invasive species. Interdisciplinary collaborators include a cognitive scientist specializing in the integration of perception and motor control and applied biologists who are attempting to decrease the economic costs of the brown tree snake. The project emphasizes providing opportunities for early career development of biologists from diverse backgrounds, disseminating scientific results to a wide audience including web materials, and providing lectures with an emphasis on evolution for K-12 students and the local community.