Collaborative Research: Testing Hypotheses about Rates of Diversification & Controls on Diversification related to the Opportunities for Speciation vs Fate of Incipient Diverge

合作研究：检验有关多元化率的假设

• 批准号: 2114071
• 负责人: JoVonn Hill
• 金额: $ 48.73万
• 依托单位: Mississippi State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2114071&HistoricalAwards=false
• 关键词: Collaborative; Research; Testing; Hypotheses; about; Collaborative; Research; Testing; Hypotheses; about

All of combined planetary biodiversity owes its existence to the formation of new species. It is the newly formed boundaries separating one group of individuals from others that maintain the distinct and unique characteristics of individuals in each species. New species can form quickly or slowly. Depending upon this pace of species formation (i.e., the rate of diversification), the numbers of species within a group will differ. However, the diversification rate itself is not sufficient to understand why species diversity varies because there are multiple potential explanations for any estimated diversification rate. This research project will focus on statistically distinguishing among these different explanations in order to understand why species diversity differs across space, time, and among different groups of organisms. Specifically, by applying newly developed statistical models of species formation to genomic sequences from individuals collected across multiple populations within each of several hundred species, the research will distinguish between various potential controls on diversification. These alternative controls have never previously been tested within a single study. As such, the research will provide unprecedented insights into how the frequency of formation and persistence of isolated populations (and hence, the opportunities for new species to form) affects diversification rates. The targeted study group (North American Melanoplinae grasshoppers) includes representatives that span the climatic, geographic, and ecological conditions theorized to affect species formation, which will provide robust tests of how biodiversity is shaped. By illustrating the utility of population-level sampling within species in tests of species formation, the project will set a new benchmark for other researchers to consider for their own biodiversity studies. Such research is important to avoid misinterpretations about why biodiversity differs across geographic regions, or among habitats, or among groups of organisms that co-occur. The research will also highlight the importance of museum collections for genomic-era biodiversity studies, while enhancing this publicly accessible community resource through the addition of newly collected and curated specimens, including their DNA, ecological and geographic information. A complementary program of public and educational outreach activities built around the core research objective of why diversification might be promoted (or inhibited) across different landscapes or organismal groups will reach a diverse audience.Diversity differences observed across taxonomic groups reflect different rates of diversification. However, there are two fundamentally different controls on diversification dynamics (meaning there are different explanations for any given diversification rate): the evolution of reproductive isolation that affects the fate of incipient divergences versus the frequency with which isolated populations form and persist affecting the opportunities for speciation. Because diversification studies are typically carried out on phylogenetic estimates of species lineages, it has not been possible to test hypotheses about the opportunities for speciation. This research addresses this knowledge gap. Through combined theoretical and empirical studies and the generation of large-scale genomic data, the research will apply newly developed analytical methods to test hypotheses about diversification rates (based on phylogenetic estimates of species lineages) vs. the controls on diversification dynamics (based on phylogenetic estimates of species and population lineages). By testing for linkages between different controls on diversification dynamics with factors potentially affecting the formation of new species (e.g., fragmented habitats, topographically complex landscapes, or periods of climatic change, and species-specific traits), the work will address why these conditions might promote or inhibit the formation of new species. This will be the first study to establish potential linkages between the various controls on diversity dynamics (e.g., topographic complexity, geologic and climatic events, and selectively driven divergence). Leveraging the researchers’ extensive specimen collections with advances in collecting large-scale genomic data across hundreds of thousands of individuals and state-of-the-art analytics, the empirical dataset will contain almost complete taxonomic coverage of over 600 closely related grasshopper species (355 of which are from a single genus) that radiated recently (i.e., within the Pleistocene and Pliocene) in North America and Mexico. By combining the skillsets of researchers with taxonomic expertise and genomic and quantitative analytics, the research team will promote broad training and mentoring of graduate students, while also offering public and educational outreach activities developed by researchers with different backgrounds to reach diverse audiences and underserved communities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

所有联合行星生物多样性都归功于其形成新物种。这是将一组个人与他人分开的新形成的边界，它保持了每个物种中个体的独特和独特特征。新物种可以快速或缓慢形成。根据物种形成的速度（即多样化的速度），一组中的物种数量会有所不同。但是，多元化率本身不足以理解为什么物种多样性会有所不同，因为对于任何估计的多元化率都有多种潜在的解释。该研究项目将着重于在这些不同的解释中统计上区分这些不同的解释，以了解为什么在空间，时间和不同生物体之间的物种多样性不同。具体而言，通过将新开发的物种形成的统计模型应用于几百种种群中各个人群中收集的个体的基因组序列，该研究将区分多样化的各种潜在控制。这些替代对照以前从未在一项研究中进行过测试。因此，这项研究将为孤立人群的形成频率和持久性（因此，新物种形成的机会）如何影响多样化率，为多样化的率提供了前所未有的见解。靶向研究组（北美黑色素片蚱hoppers）包括跨越气候，地理和生态条件的代表，理论上会影响物种形成，这将为生物多样性的形成方式提供可靠的测试。通过说明物种形成测试中种群水平采样的效用，该项目将为其他研究人员考虑自己的生物多样性研究树立新的基准。这样的研究对于避免关于为什么生物多样性差异的地理区域，栖息地或共同发生的组织群体之间的生物多样性差异很重要。这项研究还将强调博物馆收集对基因组时代的生物多样性研究的重要性，同时通过添加新收集和策划的标本（包括其DNA，生态和地理信息）来增强这种公开访问的社区资源。围绕核心研究目标建立的公共和教育外展活动的完整计划，即为什么会在不同的景观或有机群体之间促进（或抑制）多元化的核心研究目标，这将吸引多元化受众。各种分类群体观察到的多样性差异反映了不同的多元化率。但是，关于多样化动态的根本不同的控制有两个根本不同的控制（这意味着对任何给定的多元化率有不同的解释）：生殖隔离的演变影响初期多样性的命运与隔离人群形成并持续影响规格机会的频率的命运。由于多元化研究通常是对物种谱系的系统发育估计值进行的，因此不可能检验有关规范机会的假设。这项研究解决了这一知识差距。通过合并的理论和实证研究以及大规模基因组数据的产生，该研究将应用新开发的分析方法来测试有关多样化速率的假设（基于物种谱系的系统发育估计值）与对多样化动态的控制（基于物种和人群的系统生理估计值）。通过测试对多样化动态的不同控制与可能影响新物种形成的因素（例如，碎片栖息地，地形复杂的景观或气候变化时期和物种特异性特征的因素）之间的联系，工作将解决这些条件为什么这些条件可能会促进或促进新物种的形成。这将是第一项在多样性动态（例如地形复杂性，地质和气候事件以及选择性驱动的差异）之间建立潜在联系的研究。 Leveraging the researchers’ extensive specimen collections with advances in collecting large-scale genomic data across hundreds of thousands of individuals and state-of-the-art analytics, the empirical dataset will contain almost complete taxonomic coverage of over 600 closely related grasshopper species (355 of which are from a single genus) that radiated recently (i.e., within the Pleistocene and Pliocene) in North America and Mexico.通过将研究人员的技能与分类学专业知识以及基因组和定量分析相结合，研究团队将促进对研究生的广泛培训和心理化，同时还为具有不同背景的研究人员提供了不同背景的研究人员开发的公共和教育宣传活动，以吸引潜水员的受众和服务不足的社区。这一奖项反映了NSF的法定任务和审查范围的范围，这是通过评估良好的支持，这是通过评估的范围来弥补的。