Phylogeny and Character Evolution of Basal Asteraceae Lineages

9318279 Jansen一组生物体的系统发育或系谱树为研究其生物学的所有其他方面提供了框架：形态特征、生理适应、历史生物地理、物种形成模式以及与生态相关生物的共同进化的方向和程度。德克萨斯大学的罗伯特·詹森博士正在研究向日葵属植物、菊科植物的系统发育，特别是多角类植物的基本谱系，重点是从叶绿体和核DNA中获得新的分子数据。将采集80至120个属的样本，其中大部分来自南半球，分子数据将与传统的形态数据以及来自花粉和花药研究的新特征相补充。过去几年，叶绿体DNA数据大多来自詹森博士的实验室，这些数据彻底改变了菊科植物的系统发育研究，加上核DNA数据及其与形态特征的结合，应该会为这个在生态上具有重要意义的大型开花植物家族提供一个严格的系统发育图。菊科是世界上最大的双子叶植物家族，在系统发育上得到了很好的研究，这在很大程度上要归功于罗伯特·詹森博士将现代分子DNA分析方法应用于这些植物。其他研究将增加来自核基因的数据，并将这些数据与积累的形态知识相结合，既有传统的分类学特征，也有来自花粉和花药研究的新特征。

9318279 Jansen The phylogeny or genealogical tree for a group of organisms provides the framework for investigating all other aspects of their biology: direction and degree of change in morphological features, physiological adaptations, historical biogeography, modes of speciation, and coevolution with ecologically associated organisms. Dr. Robert Jansen of the University of Texas is studying the phylogeny of the sunflower family of plants, the Asteraceae, and in particular the basal lineages of Mutisioid taxa with emphasis on acquiring new molecular data from chloroplast and nuclear DNA. Between 80 and 120 genera, mostly from the southern hemisphere, are to be sampled, and the molecular data will be complemented with traditional morphological data as well as new characters from the study of pollen and anthers. Chloroplast DNA data, much of it from Dr. Jansen's laboratory over the last several years, have revolutionized the study of phylogeny in the Asteraceae, and the addition of nuclear DNA data and their integration with morphological characters should lead to a rigorous phylogeny for this large and ecologically important family of flowering plants. The Asteraceae, the largest family of dicots in the world, are phylogenetically well studied, due in large part to efforts by Dr. Robert Jansen to apply modern molecular methods of DNA analysis to these plants. Additional research will add data from nuclear genes and also integrate these data with accumulating knowledge of morphology, both traditional taxonomic features and new characters from pollen and anther studies.