RAPID: Ecological Reversal of Evolutionary Trends During a Climate Anomaly: Plasticity, Adaptation, and Integration of Environmental Change into Genomic and Organismal Architecture

这个项目试图了解导致水母外观在最近一次极端厄尔尼诺扰动后发生戏剧性变化的因素。然后，该项目将研究这些形态变化对水母及其共生体和水母猎物的影响。有趣的是，水母外表的变化反映了自上一次冰盛期以来15,000年来的变化。这种罕见的扰动的暂时性使得研究这一意外的自然事件变得相当紧迫。比较当前的扰动和随后的“正常”条件，以及与海洋中类似祖先的姐妹种群的比较，有可能迅速促进对生物的基因和表型与其生态和进化背景下的环境之间相互作用的理解。该项目将培训一名综合生物学的研究生，提高对具有社会经济意义的生态系统的理解，支持地方政府资源管理人员的决策，并提高对水母可塑性的理解，水母可塑性可能有助于并塑造水母水华的后果。结果将纳入新的混合在线普通教育课程的教育和宣传材料中。水母Mastigias的生态表型变异与严重厄尔尼诺现象下水母湖非生物环境和种群数量的急剧变化有关，反映了居住在帕劳一套海洋湖泊和邻近海洋地点的种群的进化趋势。该项目将采样和描述这种极端扰动的关键环境和生物细节，使人们能够研究环境变化如何与差异表达和/或基因座选择相互作用，以修正生态和进化时间尺度上的功能表型变化。方法包括在呈现两种特征形态的两个时间点测量水母乳杆菌的形态和行为表型；从那些表型不同的水母类中提取组织样本进行基因组、表观遗传和转录分析；稳定同位素分析；微生物组分析；以及环境的非生物和生物特征的表征，包括温度、盐度、氧气、pH、水透明度、营养物质、Chla、浮游细菌、浮游植物和浮游动物。类似的数据将从邻近海洋的类似祖先的姐妹种群(亚种)中收集。这些测量将揭示类似的一套基因座是否涉及塑料和对不断变化的环境的适应性反应，即是否支持Mastigias的遗传同化概念。它们还将有助于理解生物体对全球逐渐和快速的气候变化的反应，并将产生关于横跨蛇形动物生命树的同源结构变化的新假设。

This project seeks to understand the factors that lead to dramatic changes in the appearance of jellyfishes following the most recent extreme El Niño perturbation on record. The project will then examine the consequences of these changes in morphology for the jellyfish, its symbiont, and the prey of the jellyfish. Intriguingly, the changes in appearance of the jellyfishes mirror changes seen during the 15,000 years since the Last Glacial Maximum. The temporary nature of the rare perturbation generates considerable urgency to study this unanticipated natural event. Comparison of current perturbed and subsequent "normal" conditions, and comparisons with an ancestor-like sister population in the ocean, has the potential to rapidly advance understanding of interactions between an organism's genotype and phenotype, and its environment in both ecological and evolutionary contexts. The project will train a graduate student in integrative biology, improve understanding of a socio-economically important ecosystem, supporting decisions by local government resource managers, and improve understanding of plasticity in jellyfish which may contribute to, and shape, the consequences of jellyfish blooms. Results will be incorporated into education and outreach materials for a new hybrid online general education course. Ecophenotypic variation of Mastigias medusae that is associated with dramatic changes in abiotic environment and population size in Jellyfish Lake associated with a severe El Niño mirrors evolutionary trends seen among populations inhabiting a suite of marine lakes and adjacent ocean locations in Palau. This project will sample and describe key environmental and organismal details of this extreme perturbation, enabling examination of how environmental changes interact with differential expression and/or selection of loci to amend functional phenotypic variation on ecological and evolutionary time-scales. Methods include measurement of morphological and behavioral phenotypes of Mastigias medusae at two time-points presenting each of two characteristic morphologies; tissue sampling from those phenotypically distinct medusae for genomic, epigenetic, and transcriptomic analyses; stable isotope analyses; microbiome analyses; and characterization of abiotic and biotic characteristics of the environment, including temperature, salinity, oxygen, pH, water clarity, nutrients, chl a, bacterioplankton, phytoplankton, and zooplankton. Comparable data will be collected in an ancestor-like sister population (subspecies) from the adjacent ocean. These measurements will reveal whether similar suites of loci are involved in plastic and in adaptive responses to changing environments, i.e. whether there is support for the concept of genetic assimilation in Mastigias. They will also inform the understanding of organismal responses to gradual and rapid climate change globally, and will generate novel hypotheses regarding variation in homologous structures across the scyphozoan tree of life.