Collaborative Research: Modeling the Origin and Evolution of Hawaiian Plants

我们今天发现的物种不仅反映了它们的直系祖先是如何以及何时进化的，而且还反映了它们是在哪里进化的。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，在那里，岛屿的形成，侵蚀和沉降预计将推动新物种的起源。在夏威夷群岛，这样的过程已经发生了几十次，并产生了1,000多种世界上其他地方没有的开花植物物种。了解夏威夷植物群的起源和多样化有助于指导保护工作，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，以重建具有复杂地质历史的地区之间密切相关的物种群体如何，何时和何地起源，分散和灭绝。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种未充分研究的夏威夷植物种群生成一个大型基因组数据集，然后利用新开发的软件推断这种多样性是如何起源的。除了通过研究项目本身培训大量的本科生，研究生，博士后和花园附属研究人员外，还将提供两个计算植物地理学研讨会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地理学的公开教学模块。第一个目标将开发随机模型和推理方法，在时空变化的地理环境中联合模拟物种形成、灭绝和扩散过程。这些建模工具将通过开源贝叶斯遗传学软件RevBayes免费提供，以使其他研究人员能够将新方法重新用于夏威夷植物地理学之外的系统。第二个目标将重建12个未充分研究，但生态多样性，夏威夷植物辐射的地理历史。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Angiosperm-353协议生成标准化的基因组数据集，用于两个目的。首先，通过评估新的植物基因组数据与形态，生态和地理数据，研究人员将解决长期存在的关于12种植物辐射分类的难题，包括生态和形态上独特的属。第二，新的系统发育软件将被用来推断进化关系，起源时间和地理历史的植物群，以获得新的见解，对岛屿植物辐射的地理驱动程序。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

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.