Developmental plasticity and adaptive capacity of the cardiorespiratory system of fishes and amphibians

我们的研究项目利用水生动物来解决进化生态学和发育生物学中的紧迫问题。这项研究是多学科的，并有一个长期的目标，即了解动物与环境之间复杂的相互作用。了解心肺系统的发展和适应是我们研究的核心组成部分。心肺系统的极限决定了动物进行有氧运动的能力，如果心肺系统不能满足对氧气的基本需求，就会导致死亡。心输出量代表心脏向组织输送含氧血液的能力，是一种重要的生理特征，它决定了环境与健康之间的关系。直接测量血流量是确定心输出量的金标准，但在过去，由于需要插入心脏探针的侵入性和耗时的手术而受到限制。最近，技术进步使得使用外部多普勒探头测量血流成为可能。因此，目前的拨款要求资助购买多普勒流速系统，该系统将能够实时、微创地测量水生动物的心输出量，并将成为加拿大第一个专门用于研究鱼类和两栖动物的多普勒流速系统。在未来5年，该RTI所要求的设备将用于开展4个重大项目，将培养8名研究生，10名本科生和2名博士后。第一个项目将侧重于了解鱼类的热生态，因为它与种群对气候变化的适应能力和保护繁殖计划的设计有关。第二个项目将使用斑马鱼作为模式生物来研究在第一个项目中被确定为介导心脏发育和心输出量的候选基因。第三个项目将侧重于了解与青蛙变态相关的心输出量的发育变化，以及生理限制如何影响这一脆弱生命阶段的死亡率。第四个项目将研究与替代生殖策略和觅食生态相关的破坏性选择如何形成心输出量的变化。这四个项目将通过解决生物学的基本问题来推进我们的研究计划，同时提供对管理和保护宝贵的加拿大鱼类和两栖动物至关重要的实用知识。

Our research programs use aquatic animals to address pressing questions in evolutionary ecology and developmental biology. This research is multi-disciplinary and shares a long-term objective to understand the complex interactions between animals and their environments. Understanding the development and adaptation of the cardiorespiratory system is a central component of our research. The limits of the cardiorespiratory system determine an animal’s capacity to perform aerobic activities, and if the cardiorespiratory system is unable to meet baseline demands for oxygen it will result in death. Cardiac output represents the capacity of the heart to deliver oxygenated blood to tissues, and is an important physiological trait that shapes the relationship between environments and fitness. Direct measurements of blood flow are the gold-standard for determining cardiac output, but in the past have been limited by the need for invasive and time-consuming surgery to insert cardiac probes. Recently, technological advances have enabled blood flow to be measured using an external Doppler probe. The present grant thus requests funding to purchase a Doppler Flow Velocity System, which will enable real-time, minimally invasive measurements of cardiac output in aquatic animals, and would be the first Doppler Flow Velocity System in Canada dedicated to the study of fishes and amphibians. Over the next 5 years, the equipment requested in this RTI will be used to conduct four major projects that will train 8 graduate students, 10 undergraduate students and 2 postdoctoral fellows. The first project will focus on understanding the thermal ecology of fishes as it relates to the resiliency of populations to climate change and the design of conservation breeding programs. The second project will use zebrafish as a model organism to study key genes that are identified as candidates to mediate heart development and cardiac output in the first project. The third project will focus on understanding developmental changes in cardiac output associated with metamorphosis in a frog and how physiological constraints affect mortality at this vulnerable life stage. The fourth project will examine how disruptive selection associated with alternative reproductive tactics and foraging ecology has shaped variation in cardiac output. Together the four projects will advance our research programs by addressing fundamental questions in biology, while providing practical knowledge that will be critical for managing and safeguarding valuable Canadian fishes and amphibians.