DISSERTATION RESEARCH: Adaptive Radiation and Interspecific Gene Flow in High Andean Espeletiinae: A Coalescent Approach

论文研究：安第斯山高地 Espeletiinae 的适应性辐射和种间基因流：合并方法

• 批准号: 9623696
• 负责人: Barbara Schaal
• 金额: $ 1.32万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-06-01 至 1998-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9623696&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Adaptive; Radiation; Interspecific

9623696 Schaal Research funded by this award probes the workings of adaptive radiation, one of the fundamental evolutionary processes that foster biodiversity. Adaptive radiation is manifest in groups of species which, from their origins in a single common ancestor, have experienced exceptional and often rapid diversification. In plants, this phenomenon is most apparent within high elevation tropical habitats. In the Andes mountains of northern South America, the subtribe Espeletiinae (Asteraceae) has diversified into over 80 species and a spectacular array of morphological forms, making it a classic example of adaptive radiation and an important model system for studying evolution in plants. One of the many interesting characteristics of this group is the high frequency with which several highly inter-fertile species of Espeletiinae co-occur within the same habitats. This raises the main questions addressed in this award: how often do such species hybridize, and what role has hybridization played in the adaptive radiation of this group? The potential for hybridization to spread adaptive genes from one species to another and even result in the instant creation of new species makes these questions particularly fascinating. With support from this award, genetic samples will be collected from many individuals of these co-occurring species. Variation among these individuals and species, detected by DNA sequencing, will be analyzed using the statistically powerful framework provided by recent theoretical advances in coalescent theory, making it possible to test for evidence of genetic exchange among species. Results will provide answers to basic questions about the role of hydridization, not just in the adaptive radiation of the Espeletiinae but it all plants where hydridization may play an important role in evolution. Findings will enhance our knowledge of tropical biodiversity and aid in conservation strategies for endemic plant species.

小行星9623696 该奖项资助的研究探索了适应性辐射的作用，这是促进生物多样性的基本进化过程之一。 适应性辐射在物种群体中表现得很明显，这些物种从其单一的共同祖先开始，就经历了异常和往往迅速的多样化。 在植物中，这种现象在高海拔热带栖息地中最为明显。 在南美洲北方的安第斯山脉，埃斯佩蒂亚族（菊科）已分化为80多个物种和一系列壮观的形态形式，使其成为适应辐射的经典例子和研究植物进化的重要模式系统。 这一组的许多有趣的特点之一是高频率与几个高度互育物种的Espeletiinae共同出现在同一栖息地。 这就提出了这个奖项所要解决的主要问题：这些物种杂交的频率有多高，杂交在这个群体的适应性辐射中扮演了什么角色？ 杂交将适应性基因从一个物种传播到另一个物种，甚至导致新物种的即时创造，这使得这些问题特别令人着迷。 在该奖项的支持下，将从这些共存物种的许多个体中收集遗传样本。 通过DNA测序检测到的这些个体和物种之间的差异，将使用最近在结合理论方面的理论进展所提供的统计学上强大的框架进行分析，从而有可能测试物种之间遗传交换的证据。 结果将提供答案的基本问题的作用，不只是在适应性辐射的Espeletiinae，但它所有的植物在进化过程中的作用可能发挥重要作用。 研究结果将提高我们对热带生物多样性的认识，并有助于地方性植物物种的保护战略。