Species complexes in the sea: model systems for studying the biodiversity and evolutionary history of the Indo-West Pacific reef biota

海洋物种复合体：研究印度-西太平洋珊瑚礁生物群生物多样性和进化历史的模型系统

• 批准号: 0221382
• 负责人: Gustav Paulay
• 金额: $ 34.21万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-15 至 2006-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0221382&HistoricalAwards=false
• 关键词: Species; complexes; sea; model; systems

Coral reefs are arguably the most diverse and vulnerable coastal ecosystems and are currently undergoing unprecedented decline. Both their diversity and vulnerability are influenced by genetic structuring, the spatio-temporal scale and pattern of geographic differentiation within and among species. By documenting such structuring, we gain a better understanding of the origin and distribution of reef biodiversity. Furthermore, data on the level and scale of genetic interconnections are crucial for predicting reef response in the face of stressors and for the design of appropriate conservation strategies. On the basis of morphological species ranges, previous workers have generally characterized reef organisms as widespread, especially in the Indo-West Pacific (IWP), the largest and most diverse marine region. Wide species ranges in the IWP imply dispersal across numerous, vast, open ocean barriers, supporting the belief that reef organisms have tremendous dispersal abilities. Past molecular studies found IWP populations to be typically interconnected over basinal to sub-basinal scales. However recent studies on stomatopods in Indonesia and supratidal crustaceans in the Americas encountered finer levels of genetic differentiation. These studies raise the question: is fine-scale genetic structuring common among reef organisms? Preliminary data show fine-scale genetic differentiation in several widespread, reef-associated gastropods. Each species is composed of numerous, divergent populations with ranges limited to archipelagoes or islands. Their life history attributes are typical of many reef organisms, and initial data show considerable structuring in co-occurring taxa with different life history strategies. The goals of this project are to document the extent of geographic, genetic structuring in selected reef-associated gastropods in the IWP, and to use these patterns to address questions about large-scale, spatio-temporal processes in the marine biosphere. Evolutionarily significant units (ESUs), the relevant conservation and evolutionary units, will be identified throughout the region. Hypotheses about the source and dynamics of ESUs, and thus patterns of distribution and diversification, will be tested using sequence data. The significance of the proposed work lies in the nature of fine scale genetic structuring encountered in these taxa, which makes them model systems for studies of marine speciation and biogeography, and has major implications for reef management and conservation of biodiversity. Fine-scale, but deeply divergent genetic structuring has rarely been encountered in marine taxa and only in continental settings; its occurrence on islands is unprecedented and contrary to expectations. How can organisms capable of dispersing far into Oceania differentiate on an archipelagic scale? This conundrum implies that rare dispersal events may be highly important in the spread as well as differentiation of marine populations. Exploring the phylogenetic nature of genetic structuring in independent gene trees will shed light on a variety of hypotheses about the origin of marine biodiversity and distribution of reef organisms. High levels of genetic differentiation also imply that conservation and resource management strategies on reefs need to be appropriately scaled. Understanding the size and distribution of genetically interconnected units is crucial for designing appropriate management units, such as marine protected areas. Congruent genetic structuring delineates intrinsic breaks in the distribution of reef biota and thus identifies natural management units. This project will lead to better management strategies for reef-associated marine resources, and will also have direct educational impact at several levels. The project team will be interacting with resource managers regularly. The species studied are important food organisms, and provide an excellent venue to introduce implications for resource management and thus influence reef management strategies on numerous Pacific islands. The results of this work will be disseminated regionally as well as in the scientific literature.

珊瑚礁可以说是最多样化和最脆弱的沿海生态系统，目前正在经历前所未有的衰退。 它们的多样性和脆弱性都受到遗传结构、物种内部和物种之间地理分化的时空规模和模式的影响。 通过记录这种结构，我们可以更好地了解珊瑚礁生物多样性的起源和分布。 此外，关于遗传相互联系的水平和规模的数据对于预测珊瑚礁面对压力的反应和设计适当的养护战略至关重要。 根据形态学的物种范围，以前的工作者一般认为珊瑚礁生物分布广泛，特别是在印度-西太平洋（IWP），最大和最多样化的海洋区域。 IWP中广泛的物种范围意味着分散在众多，广阔，开放的海洋屏障，支持珊瑚礁生物具有巨大的分散能力的信念。 过去的分子研究发现，IWP人口通常是相互关联的流域到亚流域尺度。 然而，最近对印度尼西亚口足类动物和美洲潮上甲壳类动物的研究发现了更精细的遗传分化。 这些研究提出了一个问题：珊瑚礁生物中的精细遗传结构是否普遍？ 初步数据显示，精细规模的遗传分化，在几个广泛的，与珊瑚礁有关的腹足类。 每个物种都是由许多不同的种群组成，其分布范围仅限于群岛或岛屿。 他们的生活史属性是典型的许多珊瑚礁生物，和初始数据显示相当大的结构在共存类群不同的生活史策略。 该项目的目标是记录在IWP选定的珊瑚礁相关腹足类的地理，遗传结构的程度，并使用这些模式来解决有关大规模的问题，在海洋生物圈的时空过程。 将在整个区域确定具有重要进化意义的单位，即相关的保护和进化单位。 关于ESU的来源和动态的假设，以及分布和多样化的模式，将使用序列数据进行测试。 拟议的工作的意义在于在这些类群中遇到的精细尺度遗传结构的性质，这使得它们的模型系统的海洋物种形成和海洋地理学的研究，并具有重大意义的珊瑚礁管理和生物多样性的保护。 精细规模，但深刻分歧的遗传结构很少遇到海洋类群，只有在大陆设置;其发生在岛屿上是前所未有的，与预期相反。 能够扩散到大洋州很远的生物是如何在群岛范围内分化的？ 这一难题意味着，罕见的扩散事件可能是非常重要的传播以及海洋种群的分化。 探索独立基因树中遗传结构的系统发育性质，将有助于阐明关于海洋生物多样性起源和珊瑚礁生物分布的各种假说。 高水平的遗传分化也意味着需要适当调整珊瑚礁的养护和资源管理战略。 了解遗传上相互关联的单位的规模和分布对于设计适当的管理单位，如海洋保护区至关重要。 一致的遗传结构划定内在的中断分布的珊瑚礁生物群，从而确定自然管理单位。 该项目将导致更好地管理与珊瑚礁有关的海洋资源的战略，并将在若干层面产生直接的教育影响。 项目团队将定期与资源经理互动。 研究的物种是重要的食物生物，并提供了一个很好的场所，介绍资源管理的影响，从而影响许多太平洋岛屿的珊瑚礁管理战略。 这项工作的结果将在区域范围内以及在科学文献中传播。