DISSERTATION RESEARCH: Investigating the role of specialist and generalist host associations in a multi-level sea anemone symbiosis

论文研究：调查专家和通才主办协会在多层次海葵共生中的作用

• 批准号: 1601645
• 负责人: Marymegan Daly
• 金额: $ 1.99万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1601645&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Investigating; role; specialist

Symbiosis is an important driver of biodiversity and shapes all levels of biological organization. As a biodiversity hotspot, tropical coral reefs achieve much of their success and diversity from a network of multi-level symbioses. Although this reliance on symbiosis is well recognized, we know very little about how genetic diversity evolves within a symbiotic marine framework. Namely, our expectations surrounding resource specialization and co-diversification come primarily from the terrestrially biased literature, whereas discordant land-sea processes that act at the population level may lead to different outcomes. This research will test evolutionary hypotheses surrounding symbiosis and resource specialization by studying multiple crustacean species that all live on the corkscrew sea anemone on Caribbean coral reefs, yet vary in their host specificity. Using genomic DNA sequencing, the researchers will identify and describe previously unrecognized cryptic species, test whether increased host specificity leads to more incidences of speciation, and whether patterns of co-evolution can be recovered among these symbionts across the entire Caribbean. This research will train one graduate student and provide undergraduate students with research opportunities in the marine and molecular evolutionary sciences. Educational materials will be developed to demonstrate co-evolutionary principles in undergraduate biology courses, and public outreach events will target the ornamental aquarium trade as all study species are collected commercially.Resource specialization is expected to leave a strong signature on the genome and play an important role in species diversification. Species with narrow ecological requirements are expected to have smaller, more fragmented habitats, smaller effective population sizes, and ultimately, reduced neutral genetic variation compared to generalists. These expectations are broadly referred to as the specialist-generalist variation hypothesis (SGVH) and are an extension of classic population genetics theory. Within a symbiotic framework, host specificity should be especially useful for testing the expectations of the SGVH because micro-evolutionary processes coupled with symbiotic association will impact the population and evolutionary dynamics of each symbiont. Symbiosis generates an a priori expectation of shared biogeographic history and co-diversification, but variation in host specificity may lead to vastly different demographic histories and evolutionary responses to historical environmental conditions. Thus, the comparison of symbiotic taxa can potentially disentangle the extrinsic forces that effect whole communities from the intrinsic aspects of species biology, shed light on co-evolutionary processes and the emergence of the symbiosis. This research will use high-throughput genomic DNA sequencing and model-based coalescent analyses to delimit and describe cryptic crustacean lineages, examine the role of specialism and generalism on the evolution of genetic diversity, and explore patterns of co-diversification, demographic expansion, and community level phylogeographic breaks across the tropical Western Atlantic. This study will expand the taxonomic scope of the tropical, marine, phylogeographic literature and provide insight into the evolutionary processes that act on marine symbioses.

共生是生物多样性的重要驱动力，并塑造了所有级别的生物组织。作为一个生物多样性热点，热带珊瑚礁从多层次的共生网络中实现了很大的成功和多样性。尽管对共生的这种依赖得到了很好的认可，但我们对共生海洋框架中的遗传多样性如何演变。也就是说，我们围绕资源专业化和共同多元化的期望主要来自陆地上有偏见的文献，而在人口水平上行动的不一致的土地生产过程可能会导致不同的结果。这项研究将通过研究居住在加勒比海珊瑚礁的开瓶器海葵上的多种甲壳类物种来检验围绕共生和资源专业化的进化假设，但其宿主特异性有所不同。使用基因组DNA测序，研究人员将识别和描述先前未识别的隐性物种，测试增加的宿主特异性是否导致了更多的物种发病率，以及在整个加勒比海的这些共生体中是否可以恢复共同进化的模式。这项研究将培训一名研究生，并为本科生提供海洋和分子进化科学的研究机会。将开发教育材料，以展示本科生物学课程中的共同进化原则，公共外展活动将以商品水族馆的贸易为目标，因为所有研究物种均被市售收集。预计资源专业化将在基因组上留下强大的签名，并发挥重要的作用并发挥重要作用。在物种多样化中的作用。与通才相比，具有狭窄生态需求的物种预计将具有较小，更零散的栖息地，较小的有效人口规模，最终会减少中性遗传变异。这些期望广义被称为专业差异假设（SGVH），是经典人群遗传学理论的扩展。在共生框架内，宿主特异性对于测试SGVH的期望特别有用，因为与共生关联结合的微观进化过程将影响每个共生体的种群和进化动力学。共生对共同的生物地理历史和共同多元化产生了预期，但是宿主特异性的差异可能导致人口统计学的历史截然不同，并且对历史环境条件的进化反应。因此，共生分类单元的比较可能会使整个社区与物种生物学的内在方面，阐明共同进化过程和共生的出现有关。这项研究将使用高通量基因组DNA测序和基于模型的合并分析来界定和描述神秘的甲壳类动物谱系，研究专家和经典主义对遗传多样性进化的作用，并探索共同变化，人口统计学扩张，以及以及人口统计学扩张，以及以及社区层面的植物地理学在热带西部大西洋上破裂。这项研究将扩大热带，海洋，植物地理文献的分类范围，并洞悉对海洋共生的进化过程。