Rhythms of a changing ocean: Chronobiology and control of reproduction in marine organisms

海洋变化的节奏：海洋生物的时间生物学和繁殖控制

• 批准号: 311406-2013
• 负责人: Mercier, Annie
• 金额: $ 1.97万
• 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: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=571588
• 关键词: Rhythms; changing; ocean; Chronobiology; control

Life and its rhythms evolved in the sea, yet our understanding of biological rhythms largely revolves around circadian and seasonal cycles in terrestrial models. My research on marine organisms strives to elucidate key interplays in cyclic life-history events, following an integrated view that combines the perspectives of chronobiology (relation between biological activity and time), phenology (relation between periodic events and climatic conditions) and evolutionary biology (adaptive benefits of biological rhythms). My long-term objective is to clarify the mediators and adaptive significance of reproductive periodicities in benthic populations. Recently we found that 24 boreal species belonging to 6 phyla undergo seasonal and lunar rhythms of reproduction with mass-spawning events similar to coral reefs, although species-specific diel components preserve reproductive isolation. We also found that deep-sea species, presumably exposed to little environmental variability, still exhibit seasonal and lunar breeding cycles. Currently proposed mechanisms and advantages of rhythmic reproductive events cannot fully explain why so many species release progeny in spring, irrespective of reproductive mode (free spawning, brooding), larval type (feeding, nonfeeding), depth or region. The short term objectives of the proposed program are to: 1) further investigate breeding periodicity in deep-sea species; 2) compare the adaptive value of periodic reproduction in species with different life histories; 3) tease out the drivers of breeding rhythms in deep-sea and boreal taxa; 4) investigate the concept of "sentinels" (organisms more receptive to environmental cues); and 5) identify circadian rhythms in species with seasonal breeding. By integrating concepts of reproductive biology, chronobiology and chemical ecology we hope to disentangle the respective roles played by biological clocks, external cues and social interactions and gain a finer understanding of benthic ecosystem functioning. Identifying the drivers of multileveled biological rhythms in marine taxa will not only provide insight into our evolutionary past but also help develop aquaculture techniques and time-scale-based management and conservation strategies.

生命及其节律在海洋中进化，但我们对生物节律的理解主要围绕陆地模型中的昼夜节律和季节周期。我对海洋生物的研究致力于阐明循环生命史事件中的关键相互作用，遵循综合观点，结合了时间生物学（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（生物节律的适应性益处）的观点。我的长期目标是阐明底栖种群繁殖周期的中介因素和适应性意义。最近我们发现，属于 6 个门的 24 个北方物种经历了季节性和月球的繁殖节律，并具有与珊瑚礁类似的大规模产卵事件，尽管物种特有的昼夜成分保持了生殖隔离。我们还发现，深海物种可能受到的环境变化很小，但仍然表现出季节性和月球繁殖周期。目前提出的节律性繁殖事件的机制和优势无法完全解释为什么如此多的物种在春季释放后代，无论繁殖模式（自由产卵、育雏）、幼虫类型（摄食、非摄食）、深度或地区。该计划的短期目标是：1）进一步调查深海物种的繁殖周期； 2）比较不同生活史物种周期性繁殖的适应性价值； 3）梳理出深海和北方类群繁殖节奏的驱动因素； 4）研究“哨兵”（更容易接受环境线索的生物体）的概念； 5）确定季节性繁殖物种的昼夜节律。通过整合生殖生物学、时间生物学和化学生态学的概念，我们希望能够理清生物钟、外部线索和社会相互作用各自发挥的作用，并更好地了解底栖生态系统的功能。确定海洋类群多层次生物节律的驱动因素不仅可以深入了解我们的进化历史，还有助于开发水产养殖技术和基于时间尺度的管理和保护策略。