Collaborative Research: Body Size, Oxygen, and Vulnerability to Climate Change in Antarctic Pycnogonida

合作研究：南极Pycnogonida的体型、氧气和对气候变化的脆弱性

• 批准号: 1341476
• 负责人: Amy Moran
• 金额: $ 29.38万
• 依托单位: University of Hawaii
• 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: 2014-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1341476&HistoricalAwards=false
• 关键词: Collaborative; Research; Body; Size; Oxygen

Beginning with the earliest expeditions to the poles, scientists have noted that many polar taxa grow to unusually large body sizes, a phenomenon now known as 'polar gigantism.' Although scientists have been interested in polar giants for many years, many questions still remain about the biology of this significant form of polar diversity. This award from the Antarctic Organisms and Ecosystems program within the Polar Sciences Division at the National Science Foundation will investigate the respiratory and biomechanical mechanisms underlying polar gigantism in Antarctic pycnogonids (commonly known as sea spiders). The project will use a series of manipulative experiments to investigate the effects of temperature and oxygen availability on respiratory capacity and biomechanical strength, and will compare Antarctic sea spiders to related species from temperate and tropical regions. The research will provide insight into the ability of polar giants to withstand the warming polar ocean temperatures associated with climate change.The prevailing hypothesis to explain the evolution of gigantism invokes shifts in respiratory relationships in extremely cold ocean waters: in the cold, oxygen is more plentiful while at the same time metabolic rates are very low. Together these effects alleviate constraints on oxygen supply that restrict organisms living in warmer waters. Respiratory capacity must evolve in the context of adaptive tradeoffs, so for organisms including pycnogonids there must be tradeoffs between respiratory capacity and resistance to biomechanical stresses. The investigators will test a novel hypothesis that respiratory challenges are not associated with particular body sizes, and will answer the following questions: What are the dynamics of oxygen transport and consumption in Antarctic pycnogonids; how do structural features related to oxygen diffusion trade off with requirements for body support and locomotion; how does body size influence vulnerability to environmental hypoxia and to temperature-oxygen interactions; and does the cold-driven high oxygen availability in the Antarctic raise the limit on body size by reducing trade-offs between diffusivity and structural integrity? The research will explore the effects of increased ocean temperatures upon organisms that have different body sizes. In addition, it will provide training for graduate and undergraduate students affiliated with universities in EPSCOR states.

从最早的极地探险开始，科学家们就注意到，许多极地类群的体型都长得异常巨大，这种现象现在被称为“极地巨人症”。尽管科学家们多年来一直对极地巨兽感兴趣，但关于这种重要的极地生物多样性的生物学问题仍然存在许多问题。该奖项由美国国家科学基金会极地科学部的南极生物和生态系统项目颁发，将研究南极巨蛛（俗称海蜘蛛）极地巨人症背后的呼吸和生物力学机制。该项目将使用一系列操纵实验来调查温度和氧气供应对呼吸能力和生物力学强度的影响，并将南极海蜘蛛与温带和热带地区的相关物种进行比较。这项研究将深入了解极地巨兽抵御与气候变化相关的极地海洋温度升高的能力。解释巨人症进化的主流假设是，在极冷的海水中，呼吸关系发生了变化：在寒冷的海水中，氧气更充足，同时代谢率非常低。这些影响共同缓解了氧气供应的限制，而氧气供应限制了生活在温暖水域的生物。呼吸能力必须在适应性权衡的背景下进化，因此对于包括螺螺虫在内的生物来说，必须在呼吸能力和对生物力学压力的抵抗力之间进行权衡。研究人员将测试一个新的假设，即呼吸挑战与特定的身体大小无关，并将回答以下问题：南极巨螺的氧气运输和消耗动力学是什么？与氧气扩散相关的结构特征如何与身体支撑和运动的要求相权衡；体型如何影响环境缺氧和温度-氧相互作用的易感性；南极寒冷导致的高氧气供应是否通过减少扩散性和结构完整性之间的权衡而提高了体型的极限？这项研究将探索海洋温度升高对不同体型生物的影响。此外，它还将为EPSCOR州附属大学的研究生和本科生提供培训。