Phylogenetic Relationships of the Ranunculidae and Basal Hamamelidae: Implications for the Early Evolution of Non-magnoliid Dicotyledons

毛茛科和基金缕梅科的系统发育关系：对非木兰科双子叶植物早期进化的启示

• 批准号: 9306533
• 负责人: Sara Hoot
• 金额: $ 12.46万
• 依托单位: Field Museum of Natural History
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1996-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306533&HistoricalAwards=false
• 关键词: Phylogenetic; Relationships; Ranunculidae; Basal; Hamamelidae

9306533 Hoot The earliest lineages of flowering plants are known only as fragmentary fossils from Cretaceous strata, against which we can compare today's living descendants in order to reconstruct the likely course of evolution of angiosperms. With living plants, systematists analyze and compare morphological features of flowers, fruits, leaves, stems, and roots in order to build hypotheses about the likely direction of change, character by character, and then search for consistency in patterns of change across these and other sources of evidence (pollen, chromosome composition, secondary plant compounds). Modern methods of DNA analysis bring new data to bear on the problem, and Dr. Sara Hoot at the Field Museum of Natural History is analyzing three plant genes in groups of flowering plants hypothesized to be early angiosperms. Two of these are chloroplast genes and one is nuclear, thereby providing an internal control on patterns of phylogenetic divergence between the two plant cell genomes; sequences for the chloroplast atp B gene will be a novel and potentially powerful source of data. %%% New DNA sequence data will be obtained from numerous species of Ranunculidae and basal Hamamelidae, angiosperms thought to be among the earliest dicot lineages of the flowering plants. Patterns of phylogenetic divergence will be analyzed from the molecular data and compared with current views based on morphological features of extant and fossil plants. Areas of agreement between the two sources of evidence will allow study of the evolution of floral form in early angiosperms; areas of disagreement will highlight weaknesses in our understanding of rates of gene evolution or of homology of anatomical characters.

小行星9306533 最早的开花植物谱系只被认为是来自白垩纪地层的碎片化石，我们可以通过比较今天活着的后代来重建被子植物进化的可能过程。 对于活的植物，系统学家分析和比较花、果实、叶、茎和根的形态特征，以建立关于可能变化方向的假设，逐个特征，然后在这些和其他证据来源（花粉、染色体组成、次生植物化合物）中寻找变化模式的一致性。 现代DNA分析方法为这个问题带来了新的数据，菲尔德自然历史博物馆的Sara Hoot博士正在分析被假设为早期被子植物的开花植物群中的三种植物基因。 其中两个是叶绿体基因，一个是核基因，从而为两种植物细胞基因组之间的系统发育分化模式提供了内部控制; ATP B基因将是一个新的和潜在的强大的数据来源。%%% 新的DNA序列数据将从许多物种的毛茛科和基础金缕梅科，被子植物被认为是最早的双子叶植物谱系的显花植物。 系统发育分化的模式将从分子数据进行分析，并与现存和化石植物的形态特征的基础上目前的观点进行比较。 这两个证据来源之间的一致领域将允许研究早期被子植物花的形式的演变;不一致的领域将突出我们对基因进化速率或解剖特征同源性的理解中的弱点。