Phylogenetic and Evolutionary Inference in the Collomia-Navarretia Clade (Polemoniaceae)

杨百翰大学的利·约翰逊博士的研究集中在一组约50种一年生植物上，这些植物属于福禄克科(Polemoniaceae)。科洛米亚属和纳瓦雷特属中的几个物种的分布非常有限，被列为联邦或个别州保护名单上的“受关注物种”。对这些物种的初步调查显示出两种意想不到的模式：两个主要物种亚群之间存在显著的形态差异，但遗传差异很小，以及被认为是同一物种的种群之间的显著遗传差异，几乎没有形态差异。导致形态分化和遗传分化之间不协调的因素和过程通常知之甚少。这个小组提供了一个研究这些过程的模型，这些过程对于理解植物多样性的本质和在物种管理工作中做出明智的决定是基本的。拟议的研究包括几个方面：1)确定物种之间的系统发育关系，为解决形态和遗传差异问题提供坚实的框架。这将通过对多个基因的DNA序列变异的比较分析和对植物的形态分析来实现。2)根据所获得的信息修改该种群的分类，并构建识别关键字，供遇到这些物种的专家和非专业人员使用。3)使用上述DNA序列变异和形态变异检验形态和遗传分化之间的不一致性假说，并检验可能导致这种不一致性的特定的遗传控制假说。4)评估与繁殖有关的形态特征与物种稀有程度之间的相关性，看看是否可以根据这些特征做出稀有程度的预测。正在采用一种同时使用形态和DNA序列数据的方法学方法，以最大限度地利用可用信息来表征这些物种的多样性。由于物种是植物保护的基本单位，了解形态变异、分子变异和稀有之间的关系对保护决策非常重要。这项研究解决了教育环境中对此类信息的需求，教育环境包括研究型大学教师、博士后、研究生和处于指导学习环境中的本科生。正在努力将代表人数不足的群体的人纳入这一研究环境。还与阿根廷的研究人员建立了重要的合作关系，这将促进该国的实地工作以及出版物的共同编写。除了预期的同行评议出版这项工作外，国际植物保护协会还将为一些鉴定手册编写或共同编写这些物种的分类处理方法，例如为非专家和专家编写的《北美植物志》。有关物种生物学和鉴定的一般信息将在互联网上的生命之树网站上免费提供。

Research by Dr. Leigh Johnson at Brigham Young University focuses on a group of about 50 species of annual plants that belong to the phlox family (Polemoniaceae). Several species in the genera of Collomia and Navarettia have very limited distributions and are listed as "species of concern" on federal or individual state conservation lists. Preliminary investigation of these species shows two unexpected patterns: substantial morphological divergence with little genetic divergence between two major subsets of species, and substantial genetic divergence with almost no morphological divergence between populations of what have been considered to be the same species. The factors and processes that cause discordance between morphological and genetic divergence are poorly understood in general. This group provides a model for investigating these processes, which are fundamental to understanding the nature of plant diversity and making informed decisions in species management efforts. The research proposed encompasses several thrusts: 1) Determining phylogenetic relationships among the species to provide a solid framework for addressing questions of morphological and genetic divergence. This will be accomplished from comparative analyses of DNA sequence variation from multiple genes, and analyzing the plants morphologically. 2) Revising the taxonomy of the group based on the information learned, and constructing identification keys for use by specialists and laypersons that encounter these species. 3) Testing hypotheses of discordance between morphology and genetic divergence using DNA sequence variation and morphological variation mentioned above, and examining a specific hypothesis of genetic control that may contribute to this discordance. 4) Assessing correlations between morphological features associated with reproduction and the degree of species rarity to see if predictions of rarity can be made based on such features. A methodological approach that uses both morphology and DNA sequence data is being followed to maximize the information available to characterize the diversity of these species. Because species are the basic units of conservation in plants, understanding the relationship between morphological variation, molecular variation, and rarity is important for conservation decisions. This research addresses the need for such information in an educational setting that includes research university faculty, post-doctoral students, graduate students, and undergraduate students in a mentored learning environment. Effort is being made to include persons from underrepresented groups within this research environment. An essential collaborative tie has also been established with researchers from Argentina that will facilitate fieldwork in that country as well as co-authorship of publications. In addition to anticipated peer-reviewed publication of this work, the PI will be author or co-author of taxonomic treatments of these species for several identification manuals, such as the Flora of North America, that are intended for non-specialists as well as specialists. General information on species biology and identification will be made freely available from the Tree of Life web site on the internet.