Dissertation Research: Phylogenetic Relationships in the Cistaceae (Rockroses)

9972646马诺和阿灵顿岩玫瑰是北半球地中海型灌丛地的重要生态组成部分。伊比利亚半岛和美国大西洋沿岸平原的物种特别丰富。尽管在这个家族中存在着各种各样的营养和花卉特征，但cisstaceae通常以其芳香、艳丽的物种而闻名，这些物种主导着旧大陆的maquis（科西嘉人对石玫瑰的称呼）生态系统。这在很大程度上是由于它们在香水和园艺方面的经济价值，以及它们与一种壮观的寄生开花植物Cytinus （Rafflesiaceae科）的联系，这是一种根寄生虫，其唯一的地上结构是开花的茎。cisstaceae是很有前途的候选研究对象，旨在更好地了解形态形态，繁殖系统，染色体进化，生物地理学，灌木丛生态学和宿主-寄生虫关系；然而，由于缺乏可靠的自然分类，研究一直受到阻碍。这个科在很大程度上被忽视了，而且高级和低级分类学仍然模糊不清，因为传统的方案围绕着“野外可识别的”营养和花的属性，在定义自然类群的价值上几乎没有达成一致。在过去，关于什么构成原始的、专门的或趋同的特征的流行观点产生了关于文明关系的不同观点。杜克大学的研究生Jennifer Arrington在Paul Manos博士的指导下进行的这项研究，代表了自1925年以来第一个系统发育分类方法和第一个全面的分类处理。为了划分分类群和建立一个形态学矩阵用于进化分析，我们将对花的一些有前景的诊断特征，如柱头、花柱、花粉和胚珠，以及染色体数目和分蘖（花的部分数）的发育特征进行仔细的研究。所有已知的属和许多已描述的种的样本已经或即将在北美和欧洲的整个原生范围内收集到。这些信息将被基于叶绿体和核DNA序列的分子谱系所补充，这将为形态学、染色体进化、宿主特异性和生物地理学的研究提供一个比较的系统发育框架。

9972646Manos and Arrington Rockroses are ecologically important components of Northern Hemisphere Mediterranean-type shrublands. The Iberian peninsula followed by the U.S. Atlantic Coastal Plain is particularly species-rich. Even though a diverse assortment of vegetative and floral features are present in the family, the Cistaceae are usually known for their aromatic, showy-flowered species which dominate Old World maquis (Corsican for rockrose) ecosystems. This is largely due to theireconomic value to perfumery and horticulture, and their association with a spectacular parasitic flowering plant, Cytinus (family Rafflesiaceae), a root parasite whose only above-ground structure is its flowering stalk. The Cistaceae are promising candidates for studies geared toward a betterunderstanding of morphological form, breeding systems, chromosomal evolution, biogeography, shrubland ecology, and host-parasite relationships; however, research has been hindered by the lack of a reliable natural classification. The family has largely been neglected taxonomically, and higher- and lower-level taxonomy remain obscure because traditional schemes have revolved around "field identifiable" vegetative and floral attributes, with little agreement on their value in defining natural groups. In the past, prevailing ideas on what constitute primitive, specialized or convergent features have produced disparate opinions on cistalean relationships. This research by graduate student Jennifer Arrington, under the direction of Dr. Paul Manos at Duke University, represents the first phylogenetic approach to the classification of the Cistaceae and the first comprehensive taxonomic treatment since 1925. In order to delimit taxa and develop a morphological matrix for evolutionary analyses, a close examination will be made of promising diagnostic traits of the flower such as the stigma, style, pollen and ovule, as well as chromosome number and developmental characteristicspertaining to merosity (number of flower parts). Samples of all the known genera and of many of the described species have been or will soon be collected from throughout the native range of the family in North America and in Europe. This information will be supplemented by molecular genealogies based on chloroplast and nuclear DNA sequences, which will provide a comparative phylogenetic framework for research on morphological form, chromosomal evolution, host-specificity, and biogeography.