Dissertation Research: Fossil History of the Saxifragaceae sensu stricto and their Woody Relatives, Cretaceous to Pleistocene

论文研究：白垩纪至更新世虎耳草科及其木本近亲的化石历史

• 批准号: 0206185
• 负责人: William Crepet
• 金额: --
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2005-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206185&HistoricalAwards=false
• 关键词: Dissertation; Research; Fossil; History; Saxifragaceae

A grant has been awarded to Dr. William Crepet and Ms. Elizabeth Hermsen of Cornell University to review the fossil history of the angiosperm (flowering plant) family Saxifragaceae (rockfoils and other ornamentals) and the related genera Ribes (currants and gooseberries) and Itea (Virginia willow). Today, these plants occur primarily in temperate, arctic, and alpine zones of the Northern Hemisphere. Published reports of fossil saxifrages will be reevaluated and new fossil saxifrages from New Jersey will be described. Some of these fossils possess details of floral structure that will allow them to be analyzed using cladistics, a mathematical technique for determining evolutionary relationships, which is of great significance as it allows for more precise analysis of these relationships than many other methods. This will aid in the attainment of the immediate goal of this project, compilation of an accurate record of fossil saxifrages. This record will be used to study questions such as when and where saxifrages originated, when they diversified, how their reproductive biology has changed over time, and how they have acheived their current geographical distribution. It will also affect our present understanding of saxifragoid relationships, especially in light of recent DNA evidence that indicates fewer plants are true saxifrages than previously thought.One of the greatest remaining evolutionary mysteries concerns the origin, relationships, and success of the angiosperms. The vital importance of this group, demonstrated by their numerical abundance and their economic, medicinal, and ecological significance, makes solving this mystery a significant priority. This project is important in the context of the overall mystery because 1) many of the processes targeted within can be generalized to historical aspects of the angiosperm proliferation and rise to dominance and 2) because the saxifrages have been considered by some earlier workers as ancestral to many more advanced flowering plant groups.

康奈尔大学的威廉·克雷特博士和伊丽莎白·赫姆森女士获得了一笔赠款，用于审查被子植物(开花植物)、虎耳草科(岩箔和其他观赏植物)以及相关的铁杉属(醋栗和醋栗)和ITEA属(弗吉尼亚柳树)的化石历史。今天，这些植物主要生长在北半球的温带、北极和高山地带。已发表的关于萨克斯法兰化石的报告将被重新评估，并将描述来自新泽西州的新的萨克斯法兰化石。其中一些化石具有花卉结构的细节，这将使它们能够使用分支学进行分析，分支学是一种确定进化关系的数学技术，它具有重要意义，因为它允许比许多其他方法更精确地分析这些关系。这将有助于实现该项目的近期目标，即汇编一份准确的萨克斯法兰化石记录。这一记录将被用来研究一些问题，如萨克斯法兰起源于何时何地，它们何时多样化，它们的生殖生物学如何随着时间的推移而变化，以及它们如何获得目前的地理分布。这也将影响我们目前对虎耳草科植物关系的理解，特别是鉴于最近的DNA证据表明，比之前认为的更少的植物是真正的虎耳草。剩下的最大的进化谜团之一涉及被子植物的起源、关系和成功。这一群体的极端重要性，从它们的数量丰富及其经济、医学和生态意义上得到了证明，使解开这个谜团成为一个重要的优先事项。这个项目在整个谜团的背景下很重要，因为1)其中的许多过程可以概括为被子植物繁殖的历史方面，并上升为优势；2)因为一些早期的工作者认为虎耳草是许多更高级的开花植物群的祖先。