Integrative Biomechanics of Marine Mammals; Adaptations for Feeding, Diving, and Hearing in Whales

海洋哺乳动物的综合生物力学；

• 批准号: RGPIN-2019-04235
• 负责人: Shadwick, Robert
• 金额: $ 4.74万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=766141
• 关键词: Integrative; Biomechanics; Marine; Mammals; Adaptations

We study how animals work from an engineering and physics perspective. New work will focus on marine mammals, principally rorqual baleen whales. After decades of commercial exploitation with countless opportunities for study, details of their anatomy and biomechanics remained obscure until lately. Building on recent successes, our discovery research seeks to further our understanding of anatomical, physiological, and biomechanical adaptations that support their aquatic lifestyle. We will use anatomy, tissue biomechanics, and computer and digital modelling to infer physiological function in four key areas:    Lunge feeding hydrodynamics, energetics. Hydrodynamic and metabolic models of engulfment will be refined with quantified hydrodynamic performance of flexible, scaled models of rorqual tail flukes, following methods from past studies of fish tails. Combining results with computational fluid dynamics will inform mathematical energy budget models by adding realistic costs of hydrodynamic drag forces for different body sizes and speeds.     Circulatory system design for rapid pressure changes during swimming and diving. With field measured heart rate data from a collaboration, we will revisit our old hemodynamic model of the central circulation to see how flow is optimized during a dive. We will study the mechanical properties and 3D structure of thoracic and cranial vascular retia from post-mortem cases, and then use mathematical modelling to test hypotheses of how retia protect the brain from flow transients during rapid changes in internal pressures.    Respiratory system design and lung collapse at depth. We will address how nasal plugs and blowhole protect the upper airway from water incursion and how special pharyngeal structures protect the rorqual upper airway from food during swallowing. We will continue a comparative study of morphology and mechanics of lower airway structures in numerous species, using lung inflations, 3D lung and trachea anatomy from CT scans, and microscopy and composition of alveolae to determine how lungs empty in respiration and collapse at depth. Based on a hyperbaric CT scan, we will create a finite element model of thoracic compression to see how thoracic wall and diaphragm deformation compress the lungs at depth and shift blood volumes between the thorax and the thoracic and cranial retia.   Inner ear structure and hearing. We now know how to image cochlea hair cells, and have made the first spatial frequency map of a whale (beluga) cochlea with the aim of linking damage seen in stranded casualties to specific sound sources. We plan similar work on additional species, including rorquals, whose hearing capacities are unknown. Our research program on whale biomechanics will produce the most comprehensive and quantitative study of swimming, diving and feeding in the great whales, and their anatomical and physiological adaptations specific to these functions.

我们从工程学和物理学的角度研究动物是如何工作的。新的工作将集中在海洋哺乳动物，主要是长须鲸。经过数十年的商业开发和无数的研究机会，它们的解剖和生物力学细节直到最近仍然模糊不清。在最近成功的基础上，我们的发现研究旨在进一步了解支持其水生生活方式的解剖，生理和生物力学适应。我们将使用解剖学，组织生物力学，计算机和数字建模来推断四个关键领域的生理功能： 弓步进食流体力学，能量学。流体动力学和代谢模型的吞噬将细化与量化的流体动力学性能的灵活的，缩放模型的rorqual尾吸虫，以下方法从过去的研究鱼尾。将结果与计算流体动力学相结合，将为数学能量预算模型提供信息，方法是为不同尺寸和速度的物体增加流体动力阻力的实际成本。 循环系统设计，可在游泳和潜水时快速改变压力。通过一次合作的现场测量心率数据，我们将重新审视我们旧的中央循环血液动力学模型，以了解在潜水期间如何优化流量。我们将研究的机械性能和三维结构的胸部和颅骨血管retia从尸检的情况下，然后使用数学建模来测试假设retia如何保护大脑从流量瞬变在内部压力的快速变化。 呼吸系统设计和深度肺萎陷。我们将讨论鼻塞和气孔如何保护上呼吸道免受水的侵入，以及特殊的咽部结构如何在吞咽过程中保护上呼吸道免受食物的侵害。我们将继续对许多物种下气道结构的形态和力学进行比较研究，使用肺充气，CT扫描的3D肺和气管解剖，以及肺泡的显微镜和组成，以确定肺如何在呼吸中排空和在深度塌陷。基于高压CT扫描，我们将创建一个胸部压缩的有限元模型，以了解胸壁和横膈膜变形如何在深度压缩肺部，并在胸部与胸部和颅骨视网膜之间转移血容量。 内耳结构和听力。我们现在知道如何对耳蜗毛细胞进行成像，并制作了鲸鱼（白鲸）耳蜗的第一个空间频率图，目的是将搁浅伤员中看到的损伤与特定声源联系起来。我们计划对其他物种进行类似的研究，包括其听力能力未知的rorquals。 我们对鲸鱼生物力学的研究计划将产生最全面和定量的研究游泳，潜水和喂养的大鲸鱼，以及他们的解剖和生理适应具体到这些功能。