Collaborative Research: Modeling the Origin and Evolution of Hawaiian Plants

我们今天发现的物种生活的地方不仅反映了它们的直系祖先是如何以及何时进化的，还反映了它们进化的地点。地质和进化历史之间不可分割的关系在火山岛系统中尤为明显，在火山岛系统中，岛屿的形成、侵蚀和下沉预计会推动新物种的起源。在夏威夷群岛，这样的过程发生了几十次，产生了世界上其他地方找不到的1000多种开花植物。了解夏威夷植物群的起源和多样化可以帮助指导保护工作，特别是对稀有植物。这项研究将开发一套新的统计建模软件，以重建在具有复杂地质历史的地区中，密切相关的物种群体是如何、何时、何地起源、分散和灭绝的。该项目将整合现有的博物馆藏品和新收集的植物标本，为近400个未被充分研究的夏威夷植物种群生成一个大型基因组数据集，然后推断这种多样性是如何通过新开发的软件产生的。除了通过研究项目本身培训众多本科生、研究生、博士后和花园附属研究人员外，还将提供两个计算机生物地理学讲习班来培训早期职业研究人员，并将开发一系列关于夏威夷植物生物地理学的公开教学模块。该项目有两个总体目标。第一个目标将发展随机模型和推理方法，以共同模拟时空变化地理背景下的物种形成、灭绝和扩散过程。这些建模工具将通过开源的贝叶斯系统发育软件RevBayes免费提供，使其他研究人员能够将新方法用于夏威夷植物生物地理学以外的系统。第二个目标是重建12个未被充分研究但生态多样化的夏威夷植物辐射的生物地理历史。为此，研究人员将收集新的植物和组织，以完成由国家热带植物园管理的几个属级收集。然后，研究人员将使用被子植物-353协议生成标准化的系统基因组数据集，用于两个目的。首先，通过将新的系统基因组数据与形态学、生态学和生物地理学数据相结合进行评估，研究人员将解决关于12种植物辐射分类的长期难题，包括生态和形态上独特的属。其次，新的系统发育软件将用于推断植物群的进化关系、起源时间和生物地理历史，以获得对岛屿植物辐射的生物地理驱动因素的新见解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Where we find species living today reflects not only how and when their direct ancestors evolved, but also where they evolved. The inseparable relationship between geological and evolutionary history is especially pronounced in volcanic island systems, where the formation, erosion, and subsidence of islands are expected to drive the origin of new species. Within the Hawaiian Islands, such processes have occurred dozens of times and given rise to over 1,000 flowering plant species found nowhere else in the world. Understanding how the Hawaiian flora originated and diversified can help direct conservation efforts, particularly for rare plants. This research will develop a suite of new statistical modeling software to reconstruct how, when, and where groups of closely related species originate, disperse, and go extinct among regions with complex geological histories. The project will integrate existing museum collections and newly collected plant specimens to generate a large genomic dataset for nearly 400 understudied Hawaiian plant populations, then infer how this diversity originated with the newly developed software. In addition to training numerous undergraduate, graduate, postdoctoral, and garden-affiliated researchers through the research project itself, two computational biogeography workshops to train early career researchers will be offered, and a series of publicly available teaching modules on the biogeography of Hawaiian plants will be developed.The project has two overarching objectives. The first objective will develop stochastic models and inference methods to jointly model speciation, extinction, and dispersal processes in the context of a spatiotemporally variable geography. These modeling tools will be made freely available through the open source Bayesian phylogenetics software, RevBayes, to enable other researchers to repurpose the new methods for systems apart from Hawaiian plant biogeography. The second objective will reconstruct the biogeographical histories of 12 understudied, but ecologically diverse, Hawaiian plant radiations. For this, the researchers will collect new plants and tissues to complete several genus-level collections managed by the National Tropical Botanical Garden. The researchers will then generate standardized phylogenomic datasets, using the Angiosperm-353 protocol, for two purposes. First, by evaluating the new phylogenomic data in concert with morphological, ecological, and biogeographical data, the researchers will resolve long-standing puzzles regarding the taxonomy of the 12 plant radiations, including ecologically and morphologically distinctive genera. Second, the new phylogenetic software will be used to infer evolutionary relationships, origination times, and biogeographical histories for the flora, to gain new insights into the biogeographical drivers of island plant radiations.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.