Evolution of a functionally robust, high-performance musculoskeletal system

功能强大、高性能的肌肉骨骼系统的进化

• 批准号: 1350929
• 负责人: Stephen Deban
• 金额: $ 45.27万
• 依托单位: University of South Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1350929&HistoricalAwards=false
• 关键词: Evolution; functionally; robust; performance; musculoskeletal

Environmental temperature has strong effects on the physiological processes of animals such as amphibians whose body temperature is determined by their surroundings. Activity of such ectothermic animals is limited by the slowing of physiological processes at low temperatures, notably the speed and power of muscle contraction. In contrast to the thermal sensitivity of muscle-powered movements, the ballistic feeding movements of some ectothermic animals are scarcely affected by environmental temperature. Performance is maintained at a high level across a broad range of temperatures by virtue of an elastic-recoil mechanism. This 'bow and arrow' mechanism allows muscles to contract slowly and stretch tendon-like structures, which subsequently recoil rapidly to power movement. Because the speed of elastic recoil of collagen has a much lower temperature sensitivity than the speed of muscle contraction, such elastically powered movements display greater thermal robustness, potentially expanding the animal's thermal range. This research will examine the physiological basis for the evolution of high performance and thermal robustness in elastically powered movements. The research will focus on evolutionary transitions in performance of the integrated system as well as in the underlying motor control, morphology, biomechanics, and muscle contractile physiology. This study will also test the hypothesis that elastic systems evolve from non-elastic systems via the modification of existing anatomical structures rather than through fundamental changes in muscle physiology. A generalized model of elastic recoil will be applied to a focal ectothermic system--ballistic feeding in salamanders--in which extreme performance and thermal robustness have evolved multiple times in parallel. The research will make testable predictions about the robustness to environmental challenges of other diverse musculoskeletal systems with and without elastic components. Graduate, undergraduate and postdoctoral students will be trained in a wide range of scientific skills and activities, including field and laboratory procedures, participation at scientific meetings, and dissemination of results. An interactive online simulation of an elastic system (ballistic feeding in a salamander) will be developed to be used in teaching and by laypersons. Partnership with local K-12 teachers and a biology professor in Mexico will provide training as well as laboratory and field experiences to US and Mexican researchers, teachers and students. Research experiences for teachers will enhance the development of K-12 science educators and support the delivery of new research findings in a cross-curricular framework to classrooms in a large and diverse school district.

环境温度对两栖类等动物的生理过程有很强的影响，它们的体温是由周围环境决定的。这种恒温动物的活动受到低温下生理过程减慢的限制，特别是肌肉收缩的速度和力量。与肌肉运动的热敏感性相反，一些变温动物的弹道进食运动几乎不受环境温度的影响。凭借弹性反冲机制，在广泛的温度范围内保持高水平的性能。这种“弓和箭”的机制允许肌肉缓慢收缩，拉伸类似肌腱的结构，随后迅速反冲以进行动力运动。由于胶原蛋白弹性反冲的速度比肌肉收缩的速度对温度的敏感性低得多，这种弹性动力运动显示出更大的热稳健性，潜在地扩大了动物的热范围。本研究将探讨在弹性动力运动中高性能和热健壮性进化的生理基础。该研究将集中于综合系统性能的进化转变，以及潜在的运动控制、形态学、生物力学和肌肉收缩生理学。本研究还将验证一个假设，即弹性系统是通过对现有解剖结构的修改而不是通过肌肉生理学的根本变化从非弹性系统进化而来的。弹性后坐力的广义模型将应用于焦点恒温系统-蝾螈的弹道进食-其中极端性能和热鲁棒性并行发展了多次。该研究将对具有或不具有弹性成分的其他不同肌肉骨骼系统对环境挑战的稳健性做出可测试的预测。研究生、本科生和博士后将接受广泛的科学技能和活动方面的培训，包括实地和实验室程序、科学会议的参与以及成果的传播。一个弹性系统的交互式在线模拟（蝾螈的弹道喂养）将被开发用于教学和外行人。与墨西哥当地K-12教师和一位生物学教授的伙伴关系将为美国和墨西哥的研究人员、教师和学生提供培训以及实验室和实地经验。教师的研究经验将加强K-12科学教育工作者的发展，并支持在跨学科框架下向大型多样化学区的教室提供新的研究成果。