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

大多数鱼通过把食物吸进嘴里来捕捉食物，而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，但是这些肌肉力量从何而来呢？鱼头的肌肉很小，但身体的肌肉很大。鱼类是否会将身体的力量转移到头部，就像棒球投手将腿部和核心的力量转移到投掷臂一样？3D x射线成像的最新发展使直接测量能量成为可能，该项目将使用新技术XROMM （x射线运动形态重建）来研究具有不同体型和摄食习性的鱼类。这项研究的意义是为了解30,000种鱼类（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吸食的生物力学、生态学和进化。这个计划将会吸引来自普罗维登斯国际扶轮公立学校的孩子们参加课后海洋生物科学营，提供一个机会与来自传统上在科学领域未被充分代表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（移动形态视频重建），具有与XROMM相似的功能，但使用摄像机而不是昂贵的x光机。vrom将通过使技术更广泛地可用来加速研究，并通过技术创新提高美国的经济竞争力。最近一项对大口黑鲈的研究表明，轴向肌肉为高效吸食提供了95%以上的力量，但到目前为止，这些结果只来自一个物种。轴向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六种不同体型和与大口黑鲈有遥远系统发育关系的鱼类的头部和轴向肌肉组织相对于吸力进食所需的力量容量。采用xrom结合动态内灌法测量口腔体积变化的瞬时速率，采用压力传感器测量口腔压力。压力乘以体积变化率将产生瞬时吸力。最佳肌肉力量容量（Popt）将从肌肉质量和鱼肌肉产生的最大功率计算出来，假设在最佳速度下缩短。实际肌肉速度将用xrom和荧光显微法测量，并计算速度校正功率容量（Pvc）。将颅肌和轴肌的Pvc与吸力喂养所需的功率进行比较，以确定颅肌可以提供的最大功率，从而确定轴肌必须提供的最小功率。这些结果可能为研究吸力喂养提供了一个新的框架，在这个框架中，轴向肌肉骨骼系统的解剖学、生物力学和进化应该作为喂养的动力来源进行研究，或者至少作为游泳和喂养需求之间的妥协。

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.