Collaborative Research: Evolution and Systematics of the Neotropical Clade of Schefflera (Araliaceae)

合作研究：鹅掌柴新热带分支（五加科）的进化和系统学

• 批准号: 1556139
• 负责人: Gregory Plunkett
• 金额: $ 47.39万
• 依托单位: New York Botanical Garden
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1556139&HistoricalAwards=false
• 关键词: Collaborative; Research; Evolution; Systematics; Neotropical

A major goal of botanists is to describe and name the vast diversity of plant species found on our planet and to understand how, when, and where plants evolved. This is particularly challenging for groups with very large numbers of species, especially when they are difficult to observe because they grow in hard to reach places. Tropical trees are among the most under-studied plants, creating a significant gap in our knowledge. To overcome this gap, an efficient and effective strategy is needed to discover, describe, understand and conserve this large and important part of the world's biodiversity. This research project will develop a streamlined strategy, using the genus Schefflera (a member of the ivy family, Araliaceae) in tropical America as a model group. More than 400 species of Schefflera occur in this vast region, especially in the very mountainous areas of the northern Andes. Many of these species have only been seen by scientists once or a few times, and almost half do not yet have scientific names. Moreover, very few tools are available to recognize and identify these ecologically important plants, and we know almost nothing about how they evolved into so many different forms, or how they were able to adapt to the wide range of habitats. The strategy of this study, which includes field work in four Andean countries (Bolivia, Colombia, Ecuador and Peru), aims to improve our understanding of these evolutionary processes. It will also focus on identifying and naming the species that occur in a limited number of places and are most threatened with extinction (mostly by tropical deforestation) so that they can be targeted by conservation efforts. The information generated by the project will be made available on-line to a wide range of users, both within and beyond the scientific community. To help develop the next generation of plant systematists, undergraduate students will be trained in summer internship programs at the Missouri and New York Botanical Gardens, and more advanced students will participate in a tropical field botany program, joining the project scientists to gain hands-on experience during field work in South America.The research will involve constructing phylogenies for the species of Andean Schefflera using DNA-based evidence, taking advantage of recent advances in technology, especially high-throughput approaches to DNA sequencing. The phylogenies will provide a greater understanding of the major lineages of these 400+ species, which in turn will provide a framework for classifying and naming them, and for understanding their evolutionary and geographic relationships. A streamlined 'green-listing' approach to assessing conservation status of the species that are most likely to be threatened will inform priorities for naming and conserving new and rare Andean members of Schefflera. Intensive herbarium studies will provide sources of geographic, morphological, and molecular data, and will guide field work in the countries of the central and northern Andes, targeting sites with the highest concentration of species that remain unsampled, and focusing on areas in southern Ecuador and northern Peru where the group appears to have undergone exceptional diversification. Time-dated phylogenies will be used to explore biogeographic scenarios and to test for correlations among morphology, ecology, geography and evolutionary history, providing insights into the evolution of plant diversity in the Andes. These studies will be conducted with the collaboration of local botanists and students from each of the four South American countries where field work will be done. This will promote a long-term network of international researchers capable of sustaining the long-term goals of fully documenting and understanding the tremendous diversity of Schefflera in the tropical Andes.

植物学家的一个主要目标是描述和命名我们星球上发现的大量植物物种，并了解植物是如何、何时以及在何处进化的。这对于拥有大量物种的群体来说尤其具有挑战性，特别是当它们生长在难以到达的地方而难以观察时。热带树木是研究最不充分的植物之一，在我们的知识中造成了巨大的空白。为了克服这一差距，需要一种高效和有效的战略来发现、描述、理解和保护世界生物多样性的这一重要组成部分。这个研究项目将开发一个简化的策略，使用热带美洲的舍弗勒属（常春藤科，五加科的一员）作为模型组。在这片广阔的地区，特别是在安第斯山脉北部的山区，有400多种舍弗勒拉。其中许多物种只被科学家们见过一次或几次，几乎一半的物种还没有学名。此外，很少有工具可以用来识别和识别这些具有重要生态意义的植物，我们几乎不知道它们是如何进化成这么多不同的形式的，或者它们是如何适应广泛的栖息地的。这项研究的策略包括在四个安第斯国家（玻利维亚、哥伦比亚、厄瓜多尔和秘鲁）进行实地工作，旨在提高我们对这些进化过程的理解。它还将专注于识别和命名在有限的地方出现的最受灭绝威胁的物种（主要是由于热带森林砍伐），以便它们可以成为保护工作的目标。该项目产生的信息将在网上提供给科学界内外的广泛用户。为了帮助培养下一代植物系统学家，本科生将在密苏里和纽约植物园的暑期实习项目中接受培训，更高级的学生将参加热带野外植物学项目，与项目科学家一起在南美洲的野外工作中获得实践经验。这项研究将包括利用DNA为基础的证据，利用最新的技术进步，特别是高通量的DNA测序方法，构建安第斯雪弗勒拉物种的系统发育。系统发生学将为这400多个物种的主要谱系提供更好的理解，从而为它们的分类和命名提供一个框架，并为理解它们的进化和地理关系提供一个框架。一种简化的“绿色名录”方法来评估最有可能受到威胁的物种的保护状况，将为命名和保护新的和稀有的安第斯Schefflera成员提供优先事项。密集的植物标本室研究将提供地理、形态和分子数据来源，并将指导安第斯山脉中部和北部国家的实地工作，目标是未采样物种最集中的地点，并将重点放在该群体似乎经历了异常多样化的厄瓜多尔南部和秘鲁北部地区。时间确定的系统发育学将用于探索生物地理情景，并测试形态学、生态学、地理学和进化史之间的相关性，为安第斯山脉植物多样性的进化提供见解。这些研究将在进行实地工作的四个南美国家的当地植物学家和学生的合作下进行。这将促进国际研究人员的长期网络，能够维持充分记录和了解热带安第斯山脉谢弗勒拉巨大多样性的长期目标。