Reproduction and dispersal strategies in extreme environments: insights into persistence and shifts in marine biodiversity

极端环境中的繁殖和扩散策略：深入了解海洋生物多样性的持久性和变化

• 批准号: RGPIN-2020-07018
• 负责人: Mercier, Annie
• 金额: $ 2.91万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741551
• 关键词: Reproduction; dispersal; strategies; extreme; environments

The long-term objective of my research program is to clarify the drivers and adaptive significance of breeding and dispersal strategies in cold-water and deep-sea benthic animals, in the context of a changing ocean. Life-history events are explored from the perspectives of chronobiology (relation between biological activity and time), phenology (relation between periodic events and climatic conditions) and evolutionary biology (adaptive benefits of life-history strategies). We recently demonstrated lunar mass-spawning events in 24 boreal species belonging to 6 phyla, as well as seasonal and lunar breeding cycles in deep-sea species exposed to weak environmental variability. We also assessed the underpinnings and significance of lecithotrophy/oviparity (maternally provisioned propagules) on the continuum between planktotrophy (externally feeding propagules) and matrotrophy/viviparity (live bearing). Currently proposed advantages of rhythmic reproductive events cannot fully explain why so many species release progeny in sync, irrespective of reproductive strategies, depth or region. Moreover, historical predictions made about gradients of non-pelagic development and pelagic lecithotrophy towards the deep sea and the poles (e.g. Thorson's rule) have been both supported and challenged, calling for further study of the selective pressures at play. Extending my research program into the Arctic for this funding cycle follows a twofold premise. (1) It complements our studies along subarctic coasts and in the deep sea (representing marked and weakly seasonal environments, respectively), and allows us to test hypotheses related to photoperiod (high latitude, seasonal ice cover) and food availability (unique primary production) using the same or closely related taxa. (2) Marine species are expected to shift their distributions towards the Arctic in the face of climate change, while pressures on this environment (ocean warming, shipping and mining activities) increase, stressing the need to understand local life-history strategies to predict impacts on biodiversity. The short-term objectives are to identify (i) intra and interspecific spatial dynamics related to reproductive strategies; (ii) sources and cycles of energy storage and reproductive investment; and (iii) drivers of breeding periodicities in Arctic benthic taxa (echinoderms, cnidarians, mollusks).  Identifying drivers of breeding and dispersal strategies in Arctic marine taxa will provide insight into shifting biodiversity and distribution patterns, and assist management strategies supporting food security in Canada's northernmost communities. The interdisciplinary context of the proposed program provides opportunities for significant discoveries and for training HQPs (including Indigenous scientists) in a variety of tools and techniques inside a collaborative environment.

我的研究计划的长期目标是阐明在不断变化的海洋背景下，冷水和深海底栖动物繁殖和扩散策略的驱动因素和适应性意义。从时间生物学（生物活动与时间之间的关系）、物候学（周期性事件与气候条件之间的关系）和进化生物学（生活史策略的适应性利益）的角度探讨生活史事件。我们最近证明了6门24种北方物种的月球大规模产卵事件，以及暴露于弱环境变异性的深海物种的季节和月球繁殖周期。我们还评估了在浮游营养（外部摄食繁殖体）和营养营养/胎生（活产）之间的连续体中，卵泡营养/卵生（母系提供的繁殖体）的基础和意义。目前提出的节律性生殖事件的优势并不能完全解释为什么如此多的物种同步释放后代，而不考虑生殖策略、深度或区域。此外，关于非远洋发育和远洋岩石侵蚀向深海和两极的梯度（如Thorson规则）的历史预测既得到了支持，也受到了挑战，需要进一步研究在其中起作用的选择压力。为了这个资助周期，我的研究项目延伸到北极有两个前提。(1)它补充了我们在亚北极海岸和深海（分别代表明显和弱季节性环境）的研究，并允许我们使用相同或密切相关的分类群来测试与光周期（高纬度，季节性冰盖）和食物可用性（独特的初级生产）相关的假设。(2)面对气候变化，海洋物种的分布将向北极转移，同时对该环境的压力（海洋变暖、航运和采矿活动）增加，强调需要了解当地生活史策略来预测对生物多样性的影响。短期目标是查明(i)与生殖战略有关的种内和种间空间动态；能源储存和生殖投资的来源和周期；（iii）北极底栖动物类群（棘皮动物、刺胞动物、软体动物）繁殖周期的驱动因素。确定北极海洋分类群繁殖和扩散策略的驱动因素将有助于深入了解生物多样性和分布模式的变化，并有助于支持加拿大最北端社区粮食安全的管理策略。拟议项目的跨学科背景为重大发现和培训hqp（包括土著科学家）提供了在协作环境中使用各种工具和技术的机会。