Collaborative Research: Generic Relationships within Subfamily Bromelioideae (Bromeliaceae)

怀俄明州大学的布朗博士和霍普学院的埃文斯博士获得了一笔赠款，用于研究热带植物凤梨科凤梨亚科成员之间的进化关系。 凤梨亚科（Bromelioideae）有30属约750种，是凤梨科（Bromeliaceae）中研究最少的亚科。 凤梨亚科中几乎三分之一的物种都是以艾奇米亚属为代表的，这是一个非常可变的，几乎可以肯定是人工的属。 雀麦亚科的几个属与艾奇米亚只有一个或两个特征不同，属间的形态界限很不明确。 凤梨科是一个由多达20个凤梨亚科属组成的复合体的核心，其进化关系和系统学完全混乱。 该项目的主要目标是利用形态学和分子（DNA序列）数据来研究凤梨亚科内的关系，重点是Aechmea和密切相关的属。在密集的实地研究期间，将收集个别植物的形态信息。 由于在正常的压榨和干燥过程中，花的特征在这个家庭中保存得很差，观察活的和/或液体保存的材料是成功的系统发育分析的关键。 系统发育分析，使用最大简约法将进行分类群的字符数据矩阵产生在这个密集的形态再分析。 将从用于形态学研究的相同个体中收集三个非编码区（两个叶绿体基因间间隔区，psbA-trnH和trnL-trnF，以及核核糖体内转录间隔区）的DNA序列数据。 分子数据的系统发育分析将提供一个独立的评估形态学的同源性，以及一个工具来检查特定的形态特征的进化。 多个数据集的整合是目前系统学中一个备受讨论和争论的领域，将探讨几种比较和整合分子和形态学数据的方法。 该研究将为以下几个更广泛的科学和教育目标做出重要贡献：1）它代表了首次尝试从明确的系统发育范式中发展凤梨科凤梨亚科的系统发育关系假设。 2)它将为巴西大西洋森林生物群落这一地球上最濒危但生物多样性最丰富的生物群落之一的一个具有重要生态意义的分类群（凤梨科）的生物多样性文献工作作出重大贡献。 3)在生态学上，池生凤梨科植物是维持生物多样性的关键物种，其中包括凤梨亚科的大多数成员。 它们是树冠中自由水的重要资源，并为代表所有生命王国的许多不同生物提供觅食场所，繁殖场所和栖息地。 由此产生的系统发育假说将是重要的生物学家研究多样化，植物地理学，和可能的共同进化模式的任何生物体，利用凤梨坦克。 4)美国和巴西的学生都将接受现代系统实践和理论的培训。 5)该项目将改善巴西一所重要大学的专业植物系统学研究和教学基础设施。 6)收集的DNA样本和序列将提供给其他研究人员。 7)该项目将有助于促进美国和巴西今后开展系统的和与生物多样性有关的研究和教育合作。

A grant has been awarded to Dr. Brown at the University of Wyoming and Dr. Evans at Hope College to examine evolutionary relationships among members of the tropical plant family Bromeliaceae subfamily Bromelioideae. The Bromelioideae, with 30 genera and about 750 species, is the most poorly understood subfamily in Bromeliaceae. Almost a third of the species in subfamily Bromelioideae are represented by the genus Aechmea, an extremely variable, and almost certainly artificial genus. Several genera in Bromelioideae differ from Aechmea by only one or two characters, and the morphological boundaries among genera are very poorly defined. Aechmea forms the core of a complex of as many as 20 Bromelioideae genera for which evolutionary relationships and systematics are in complete disarray. The primary goal of this project is to utilize morphological and molecular (DNA sequence) data to examine relationships within Bromelioideae, with an emphasis on Aechmea and closely related genera. Morphological information from individual plants will be collected during intensive field studies. Because floral characteristics are poorly preserved in this family during the normal pressing and drying process, observation of live and/or liquid preserved material is critical for successful phylogenetic analysis. Phylogenetic analyses using maximum-parsimony methods will be conducted on the taxon by character data matrices produced in this intensive reanalysis of morphology. DNA sequence data from three non-coding regions (two chloroplast intergenic spacers, psbA-trnH and trnL-trnF, and nuclear ribosomal internal transcribed spacer regions) will be collected from the same individuals used for morphological studies. Phylogenetic analyses of the molecular data will provide an independent assessment of the morphological phylogenies as well as a tool to examine the evolution of specific morphological characters. Integration of multiple data sets is currently an area of much discussion and debate in systematics, and several methods for comparing and integrating the molecular and morphological data will be explored. The proposed research will contribute significanly to several broader sceintific and educational goals, as follows: 1) It represents the first attempt to develop hypotheses of phylogenetic relationships within Bromeliaceae subfamily Bromelioideae from within an explicit phylogenetic paradigm. 2) It will make a significant contribution to biodiversity documentation for an ecologically important taxon (Bromelioideae) in one of the most endangered, yet biotically diverse biomes on Earth, the Atlantic Forest Biome of Brazil. 3) Ecologically, tank-forming bromeliads, which include most members of Bromelioideae, are keystone species in biodiversity maintenance. They are an important resource for free-water in the canopy, and provide feeding sites, breeding sites, and habitat for many diverse organisms that represent all Kingdoms of life. The resulting phylogenetic hypotheses will be important to biologists studying diversification, biogeography, and possible co-evolutionary patterns of any of the organisms that utilize bromeliad tanks. 4) Both U.S. and Brazilian students will be trained in modern systematic practice and theory. 5) The project will improve professional botanical systematics research and teaching infrastructure at an important Brazilian university. 6) DNA samples and sequences collected will be made available to other researchers. 7) The project will help to stimulate future collaborative U.S. - Brazil systematic and biodiversity-related research and education.