Systematics and Comparative Ontogeny of Silicified Late Cambrian and Early Ordovician Trilobite Faunas of the Great Basin: Bridging a Phylogenetic Gap.

大盆地硅化晚寒武世和早奥陶世三叶虫动物群的系统学和比较个体发育：弥合系统发育差距。

• 批准号: 9973065
• 负责人: Stephen Westrop
• 金额: $ 18万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9973065&HistoricalAwards=false
• 关键词: Systematics; Comparative; Ontogeny; Silicified; Late

9973065Westrop The apparent phylogenetic gap between Cambrian and post-Cambrian trilobites has long been recognized as one of the fundamental problems in the history of the group. It prevents a clear understanding of the origination of new groups of trilobites during the major reorganization of marine communities that took place during the Ordovician. By comparison, relationships between major groups of post-Cambrian trilobites are well understood, and this has been achieved by the application of cladistic techniques and, especially, by comparative studies of ontogenetic development of silicified material. Similar treatment of Cambrian trilobites has been hindered by the scarcity of silicified faunas. This proposal will study newly discovered, diverse Cambrian silicified faunas of the Great Basin. They have the potential to revolutionize our understanding of the relationships between Cambrian and post-Cambrian trilobites, and to finally place the Ordovician radiation in its proper phylogenetic context.

9973065 Westrop寒武纪和后寒武纪三叶虫之间明显的系统发育差距长期以来一直被认为是该群历史上的基本问题之一。这妨碍了人们在奥陶纪期间对海洋生物群落的重大重组过程中对新的三叶虫群体的起源有一个明确的认识。通过比较，人们很好地了解了后寒武纪三叶虫主要类群之间的关系，这是通过应用分支学技术，特别是通过对硅化物质个体发育发展的比较研究来实现的。对寒武纪三叶虫的类似处理因硅化动物群的稀缺而受到阻碍。这项建议将研究新发现的寒武纪硅化动物群。它们有可能彻底改变我们对寒武纪和后寒武纪三叶虫之间关系的理解，并最终将奥陶纪辐射置于适当的系统发育背景中。