Global plant diversity patterns: case studies from early branching legume clades

全球植物多样性模式：早期分支豆科植物进化枝的案例研究

• 批准号: RGPIN-2017-05747
• 负责人: Bruneau, Anne
• 金额: $ 2.4万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=632116
• 关键词: Global; plant; diversity; patterns; case

All recent studies suggest that species diversity is distributed very evenly through time, across geographical regions and amongst lineages in phylogenetic history. Although it is widely believed that increased variability drives species diversification, teasing apart the causes of diversification remains a challenge. Research in my laboratory focuses on systematics, phylogenetics and evolution of the economically important plant family Leguminosae (Fabaceae). With 765 genera and c. 19,500 species, legumes are the third largest flowering plant family, represent one of the most spectacular examples of evolutionary diversification in plants, and occur in nearly every biome across the globe. We study the mostly tropical basal lineages of the family. The long term objective of my research is to use comprehensively sampled, robust and well-resolved phylogenies to establish stable classifications and to better understand macro-evolutionary morphological, ecological and biogeographical patterns. Three objectives will be addressed in the next five years. 1) We will examine global patterns of diversification to test for significant rate shifts across and within the five basal legume clades. To achieve this, we will generate comprehensively sampled phylogenies using a phylogenomics approach to sequence 100’s of nuclear genes. Rate shifts will be studied in relation to geography, biomes, functional traits and floral evolution. 2) Intrinsic plant-related characteristics will be studied to test for trait-dependent diversification. Floral characters will be examined in Detarioideae and Dialioideae, two lineages that exhibit remarkable diversity in floral morphology, and functional traits related to habitat adaptations will be studied in Caesalpinioideae, where radiations into all major biomes have occurred. 3) Biogeography and biome evolution will be studied in Detarioideae and Dialioideae to determine whether the distribution of these primarily wet forest clades can be traced to an early to mid-Eocene, dry environment diversification, as suggested for most legumes. Using fossil calibrated phylogenies, we will investigate present-day geographic and ecological distributions, infer ancestral biomes, look for evidence of biome shifts and critically evaluate the relative importance of biome conservatism versus geological history in explaining the distribution of these two clades. Our recent work has made significant progress towards a more robust and stable phylogenetically-based classification of legumes. The research proposed here offers scope to consolidate these efforts to clearly understand patterns of legume diversity across the globe. This collaborative and broadly based research program provides opportunities for training of students in plant systematics and evolution, which are essential to a better understanding of existing biodiversity worldwide.

最近的所有研究都表明，物种多样性在系统发育历史中随时间、地理区域和谱系分布得非常均匀，尽管人们普遍认为变异性的增加推动了物种多样化，但梳理多样化的原因仍然是我实验室的一项研究挑战。重点研究具有 765 个属和约 19,500 个物种的经济重要植物科豆科 (豆科) 的系统学、系统发育和进化。开花植物家族是植物进化多样化最引人注目的例子之一，几乎存在于全球每个生物群落中。我们研究该家族的大部分热带基础谱系，我研究的长期目标是使用全面的样本。未来五年将实现三个目标：1）我们将研究多样化的全球模式。测试五个基础豆科分支之间和内部的显着速率变化 为了实现这一目标，我们将使用系统发生学方法对 100 个核基因进行测序，以生成全面的系统发育样本，并研究与地理、生物群落和功能特征相关的速率变化。 2) 将研究与植物相关的内在特征，以测试花的特征依赖于 Detarioideae 和 Dialioideae 这两种植物的特征。将在 Caesalpinioideae 中研究在花卉形态和与栖息地适应相关的功能特征方面表现出显着多样性的谱系，其中所有主要生物群落都发生了辐射 3) 将在 Detarioideae 和 Dialioideae 中研究生物地理学和生物群落进化，以确定是否存在分布。正如大多数豆科植物的化石校准系统发育所表明的那样，这些主要湿润的森林分支可以追溯到始新世早期到中期的干燥环境多样化。将调查当今的地理和生态分布，推断祖先生物群落，寻找生物群落变化的证据，并批判性地评估生物群落保守性与地质历史在解释这两个进化枝的分布方面的相对重要性。这里提出的研究提供了巩固这些努力的范围，以清楚地了解全球豆类多样性的模式，这一合作性和基础广泛的研究项目为学生的植物培训提供了机会。系统学和进化论，这对于更好地了解全世界现有的生物多样性至关重要。