Cladistic Analyses of Viburnum Based on Molecular Characters

亚利桑那大学的迈克尔·多诺霍博士， 最初是和他的同事， 威斯康星州，计划研究进化的关系， 开花植物荚属和其他群体的关系， 强调从叶绿体DNA获得的特征。 的 叶绿体基因组将被一系列限制酶消化 酶，每种酶在特定位点切割分子， 分子上这些位点的确切位置 测定 比较核苷酸位点相似性和 物种之间的差异将允许确定 分离分类群的突变的进化模式。 评估 更远的关系，属和科之间，完成 将获得叶绿体基因的核苷酸序列， 使用计算机辅助方法进行比较。 从分子数据得出的系统发育将与 基于先前获得的形态特征的树， 并将评估一致性的性质和程度。 分子数据可能会解决仍然存在的关系 单从形态学上看是可疑的 此外，解决 系统发育树将提供一个框架，研究 感兴趣的特定形态特征的进化。 这 在水果性状方面尤其有价值， 因为这些最近已经被博士详细研究。 Donoghue和发展数据可用于这些。 使用 分析发育变化的系统发育信息， 有助于对形式演变的新兴分析， 在有机体中的功能。

Dr. Michael Donoghue of the University of Arizona, working initially with colleague Dr. Kenneth Sytsma at University of Wisconsin, plans to study evolutionary relationships within the flowering plant genus Viburnum and relationships to other groups, emphasizing characters obtained from chloroplast DNA. The chloroplast genome will be digested with a battery of restriction enzymes, each of which cleaves the molecule at specific sites, and the exact position of these sites on the molecule will be determined. Comparison of nucleotide site similarities and differences among the species will allow determination of the evolutionary pattern of mutations separating taxa. In assessing more distant relationships, between genera and families, complete nucleotide sequences of chloroplast genes will be obtained and compared, using computer-aided methods. Phylogenies derived from molecular data will be compared to trees obtained previously based on morphological characteristics, and the nature and extent of congruence will be evaluated. Molecular data are likely to resolve relationships that remain equivocal based on morphology alone. Further, resolved phylogenetic trees will provide a framework for study of the evolution of particular morphological traits of interest. This will be especially vaulable in the case of fruit characters, because these have recently been studied in detail by Dr. Donoghue and developmental data are available for these. The use of phylogenetic information to analyze developmental changes will contribute to emerging analyses of the evolution of form and function in organisms.