Determining the source of muscle power for suction feeding in ray-finned fishes

大多数鱼类通过将食物吸入口中来捕获食物，成功的吸食既快速又有力。速度和力量的结合需要肌肉的强大力量，但是所有的肌肉力量从何而来？鱼的头部肌肉很小，但身体肌肉很大。鱼是否将力量从身体转移到头部，就像棒球投手将力量从腿和核心转移到投掷臂一样？3D X射线成像的最新发展使直接测量功率成为可能，本项目将使用新技术XROMM（移动形态的X射线重建）来研究具有不同体型和食性的鱼类。这项研究的意义在于为了解30，000种鱼类（占所有脊椎动物物种的一半）的身体和头部肌肉的结构和功能提供了一个新的框架，其结果将影响全球众多实验室正在进行的研究，研究生物力学，生态学和吸力进食的进化。这个项目将吸引来自普罗维登斯国际扶轮公立学校的儿童参加课后海洋生物学科学营，提供一个机会，与来自传统上在科学领域代表性不足的群体的学生一起做有趣的科学项目。该项目将开发一种新技术，VROMM（运动形态的视频重建），具有与XROMM类似的功能，但使用摄像机而不是昂贵的X光机。VROMM将通过使技术更广泛地使用来加速研究，并通过技术创新来提高美国的经济竞争力。最近对大口黑鲈的一项研究表明，轴向肌肉为高性能的吸食提供了95%以上的动力，但这些结果迄今为止仅来自一个物种。中轴肌可能是大多数鱼类吸力的主要来源吗？本项目的目标是测量颅和轴向肌肉组织的功率容量相对于所需的吸食在六种鱼类与不同的身体形式和遥远的系统发育关系，以大口黑鲈的功率。将使用XROMM结合动态内窥镜方法测量颊侧瞬时体积变化率，并使用压力传感器测量颊侧压力。压力乘以体积变化率将产生瞬时吸力。最佳肌肉功率容量（Popt）将根据肌肉质量和鱼肌肉产生的最大功率来计算，其假设在最佳速度下缩短。将使用XROMM和荧光显微镜测量实际肌肉速度，并计算速度校正功率容量（Pvc）。将颅肌和轴肌的Pvc与吸引进食所需的功率进行比较，以确定颅肌可以贡献的最大功率，从而确定轴肌必须贡献的最小功率。这些结果可能提供一个新的框架，研究吸吮，其中的解剖结构，生物力学和轴向肌肉骨骼系统的演变应作为电源的喂养，或至少作为游泳和喂养的需要之间的妥协进行研究。

Most fish capture food by sucking it into their mouths, and successful suction feeding is both fast and forceful. Speed and force combined require high power from muscles, but where does all of that muscle power come from? Fish head muscles are small, but the body muscles are large. Do fish transfer power from their bodies to their heads, similar to the way baseball pitchers transfer power from their legs and core to their throwing arms? Recent developments in 3D X-ray imaging have made it possible to measure power directly, and this project will use the new technology, XROMM (X-ray Reconstruction of Moving Morphology), to study fish with diverse body forms and feeding habits. The significance of this research is a new framework for understanding the structure and function of body and head muscles in 30,000 species of fish (half of all vertebrate species), and the results will impact ongoing research in numerous labs worldwide studying the biomechanics, ecology and evolution of suction feeding. This project will engage children from the Providence RI public schools in an after-school Marine Biology Science Camp, providing an opportunity to do fun science projects with students from groups traditionally underrepresented in the sciences. This project will develop a new technology, VROMM (Video Reconstruction of Moving Morphology), with similar capabilities as XROMM but with video cameras instead of expensive X-ray machines. VROMM will accelerate research by making the technology more widely available and advance US economic competiveness through technological innovation.A recent study of largemouth bass showed that axial muscles provide more than 95% of the power for high-performance suction feeding, but these results so far come from just one species. Might axial muscles be the main source of suction power in most fishes? The goal of this project is to measure the power capacity of cranial and axial musculature relative to the power required for suction feeding in six species of fishes with different body forms and distant phylogenetic relationships to largemouth bass. XROMM combined with the dynamic endocast method will be used to measure instantaneous rate of buccal volume change, and a pressure transducer will be used to measure buccal pressure. Pressure multiplied by the rate of volume change will yield instantaneous suction power. Optimal muscle power capacity (Popt) will be calculated from muscle mass and the maximum power produced by fish muscle, which assumes shortening at the optimal velocity. Actual muscle velocity will be measured with XROMM and fluoromicrometry, and velocity-corrected power capacity (Pvc) calculated. The Pvc for cranial and axial muscles will be compared to the power required for suction feeding to determine the maximum power that cranial muscles can contribute, and therefore the minimum power that axial muscles must be contributing. These results may provide a new framework for studying suction feeding, in which the anatomy, biomechanics, and evolution of the axial musculoskeletal system should be studied as the power source for feeding, or at least as compromises between the needs of swimming and feeding.