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、三维运动学和力测量来研究蛇的树栖运动，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一般特征。 狭窄和圆柱形的表面，在复杂的三维树栖环境中的分支之间的倾斜和间隙提出了几个需求，非常适合确定：肌肉骨骼性能的限制和权衡，影响步态选择的近因，以及感官信息在复杂环境中用于修改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，这对功能具有普遍重要性，包括：肌腱与肌肉内收缩组织长度的比率，肌肉的横截面积，总体长与体重，以及骨骼关节的数量和活动性。 这种解剖学上的变化可能反映了灵活与僵硬、强壮与虚弱、沉重与轻盈之间的权衡，所有这些都是重要的，并且与蛇执行不同的生态相关任务特别相关，这些任务是主动弯曲以适应和抓住圆柱形表面，而不是支撑松散地覆盖在宽间隔树枝上的身体。 其中一个研究物种是棕树蛇，它在关岛造成代价高昂的停电，但确定该物种无法通行的表面，并获得关于路线选择和弥合差距的信息，应有助于管理这种破坏性的入侵物种。 跨学科合作者包括一位专门研究感知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，向广泛的受众传播科学成果，包括网络材料，并为K-12学生和当地社区提供重点进化的讲座。

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.