Molecular Systematics of Ascaridoid Nematodes

蛔虫线虫的分子系统学

• 批准号: 9208024
• 负责人: Steven Nadler
• 金额: $ 18.5万
• 依托单位: Northern Illinois University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9208024&HistoricalAwards=false
• 关键词: Molecular; Systematics; Ascaridoid; Nematodes

Nucleotide sequence data will be used to estimate phylogenetic relationships among ascaridoid nematodes. This parasite phylogeny then will serve as a framework for testing hypotheses concerning the evolution of morphological characters and life history attributes. Initial research involving direct sequencing of ribosomal-RNA and maximum parsimony analysis of these data indicates that ribosomal-RNA sequences provide a large number of informative characters and a robust phylogenetic hypothesis for ascaridoid nematodes. A more inclusive phylogeny of ascaridoids will be useful for testing competing hypotheses for the evolution of morphological characters and life cycle attributes. Analysis of evolutionary patterns for characters and attributes will be performed by applying Farris optimization to map these characters on the species cladogram inferred from the sequence data. An independent phylogenetic hypothesis based on cladistic analysis of documented morphological characters will also be developed. In addition, the molecular and morphological data sets will be used for a combined (and unweighted) phylogenetic analysis. The implications of the morphologically based and "combined" phylogenetic hypotheses for the evolution of life history attributes will also be explored by mapping. Finally, specific area of congruence and dissimilarity between the molecular and morphological data sets will be identified and examined, and the relative efficiency of phylogenetic hypotheses proposed by other researchers will be assessed independently for each data base (morphological, molecular, and combined).

核苷酸序列数据将用于估计系统发育 蛔虫之间的关系。 这种寄生虫 然后将作为测试假设的框架， 形态特征和生活史的演化 美德.先知-愿 涉及直接测序的初步研究 核糖体RNA和最大简约分析这些数据 表明核糖体-RNA序列提供了大量的 信息特征和一个强大的系统发育假说， 蛔虫 一个更具包容性的蛔虫科动物的系统发育 将有助于检验进化的相互竞争的假设 形态特征和生活史属性。 分析 角色和属性的进化模式 通过应用Farris优化来映射这些字符 在从序列数据推断的物种进化树上。 一个 基于分支分析的独立系统发育假说 还将开发记录的形态特征。 在 此外，还将使用分子和形态学数据集 用于组合的（和未加权的）系统发育分析。 的 基于形态学的和“结合”的含义 生活史进化的系统发育假说 还将通过映射来探索属性。 最后，具体 分子和分子之间的一致性和不相似性区域， 形态学数据集将被识别和检查， 其他人提出的系统发育假说的相对效率 研究人员将对每个数据库进行独立评估 （形态学、分子学和组合）。