Phylogeny and Biogeography of the Dichrostachys Group (Mimosideae Leguminosae) in Madagascar: Evidence from Morphological and Molecular Studies

马达加斯加 Dichrostachys Group（含羞草亚科豆科）的系统发育和生物地理学：来自形态学和分子研究的证据

• 批准号: 9726981
• 负责人: Melissa Luckow
• 金额: --
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9726981&HistoricalAwards=false
• 关键词: Phylogeny; Biogeography; Dichrostachys; Group; Mimosideae

9726981 Luckow Phylogeny and biogeography of the Dichrostachys group (Mimosoideae:Leguminosae) in Madagascar: evidence from morphological and molecular studies. The Madagascan biota qualifies as one of the most diverse on earth, whether one measures biodiversity using raw numbers of species, unique features, or phylogenetic position. Estimates of over 10,000 species of flowering plants have been reported from an area about 1000 miles long and 360 miles wide, and the large number of endemic species often possess extreme morphological innovations not seen in related taxa native to other regions. Thus, Madagascar offers an ideal system in which to investigate the factors influencing both speciation and morphological diversity and elaboration. An assemblage of three genera of mimosoid legumes, the Dichrostachys group has radiated widely throughout Madagascar, with all but three of approximately 30 species endemic to the island. The group provides a model system for investigating the evolution of Malagasy plants both because there are a large number of species and because they are widely distributed throughout the dry, seasonally dry, and moist forests of Madagascar. Phylogenetic analyses based on molecular and morphological data will be used to address questions relevant to systematics, pollination, and biogeography. Generic boundaries have been controversial in the Dichrostachys group, and the phylogeny will serve as a basis to define monophyletic genera. Pollinator shifts and correlations of pollinators with changes in inflorescence color and other floral traits will be examined. Of special interest will be the comparison of the pollinators of one introduced species both in Madagascan and in native South African populations. In particular this will permit us to explore such questions as: are changes in inflorescence color accompanied by a shift in pollinators? Are ontogenetic color changes associated with pollinator shifts? The phylogeny will also be used in biogeographic stu dies of areas of endemism within Madagascar. Specifically, the proposed biogeographic study will explore the relationship between speciation and geological processes, addressing questions such as: Is there a correlation between soil type and speciation in Madagascar? Is this a general phenomenon that can be measured across unrelated groups? Is there correspondence of phylogenies and geologic events indicating a general pattern of speciation through time? This investigation also will contribute primary descriptive data in the form of a monograph, an enumeration of pollinators, and the detailed mapping of species distributions. The detailed mapping of species distributions can be used to corroborate or refute generalizations about the primary vegetation types that recently have been classified using satellite imagery. The Dichrostachys group has never been monographed and there are species new to science as well as new information on previously described species. The biota of Madagascar is currently one of the most threatened in the world and the need for this work is urgent.

9726981马达加斯加的二色罗斯塔基人组（Mimosoideae：豆科）的Luckow系统发育和生物地理学：来自形态学和分子研究的证据。马达加斯加生物群岛有资格成为地球上最多样化的人之一，无论是使用原始物种，独特的特征还是系统发育位置来测量生物多样性。据报道，已经从约1000英里长，宽360英里的地区估计了超过10,000种开花植物，并且大量的特有物种通常具有其他地区的相关类群中未见的极端形态创新。因此，马达加斯加提供了一个理想的系统，可以在其中研究影响物种形态多样性和阐述的因素。 Dichrostachys组的三个属含有三属的胶质豆类，在整个马达加斯加都广泛辐射，除大约30种岛上的三个物种中，除三个外，所有岛屿都在岛上散发出来。该小组提供了一个模型系统，用于研究马达加斯加植物的演变，因为有很多物种，并且由于它们在马达加斯加的干燥，季节性干燥和潮湿的森林中广泛分布。基于分子和形态学数据的系统发育分析将用于解决与系统学，授粉和生物地理有关的问题。在二色氏菌组中，通用边界一直存在争议，系统发育将作为定义单系属的基础。将检查授粉媒介与花序颜色和其他花卉性状变化的授粉媒介的变化和相关性。特别感兴趣的是在马达加斯加和南非本地人口中的一个引入物种的传粉媒介的比较。特别是这将使我们能够探讨以下问题：花序颜色的变化是否伴随着授粉媒介的变化？与传粉媒介转移相关的个体发育色彩变化吗？该系统发育也将用于马达加斯加境内的特有区域的生物地理学。具体而言，拟议的生物地理研究将探讨物种形成与地质过程之间的关系，以解决以下问题：马达加斯加的土壤类型与物种之间存在相关性？这是可以在无关群体之间进行测量的一般现象吗？系统发育和地质事件是否存在通往时间的一般形成模式的对应关系？这项研究还将以专着的形式，传粉媒介的枚举以及物种分布的详细映射以形式的主要描述性数据。物种分布的详细映射可用于证实或反驳有关最近已使用卫星图像分类的主要植被类型的概括。 Dichrostachys组从未被专着，并且有一些新的科学物种以及有关先前描述的物种的新信息。马达加斯加的生物群岛目前是世界上受到威胁最大的生物，这项工作的需求是紧迫的。