COLLABORATIVE RESEARCH: RUI: AN INTEGRATIVE PALEONTOLOGICAL AND PALEOENVIRONMENTAL STUDY OF THE MIDDLE CAMBRIAN SPENCE, WHEELER, AND MARJUM SOFT-BODIED FAUNAS

寒武纪软体动物群的研究极大地加深了我们对后生动物演化中一些关键事件的认识。然而，谜团和未完全描述的寒武纪Burgess页岩型软体动物群仍然存在，为什么以及如何发生Burgess页岩型保存的问题也仍然存在。申请资金的拟议研究的近期目标是：1)利用犹他州最近收集的标本，准备、描述、专著斯宾塞成员和惠勒和马朱姆组中寒武纪软体动物群的新类群，并将其纳入形成学和古生物地理框架；2)使用微观分析技术在标本水平上确定化石的分类；以及3)利用新开发的显微地层学技术，将软体生物及其保存过程纳入详细的古环境框架。这项研究的智力价值是解决寒武纪古生物学和地质学中的一些谜团，从而实现多个目标。首先，识别和描述犹他州动物群的元素将有助于确定这些群系和分布在全球各地的其他寒武纪软体动物群之间共享哪些分类群。因此，可以确定这些物种和属的地层和地理范围。其次，结合先前存在的信息，可以评估Spence、Wheeler和Marjum地区各种节肢动物的系统发育关系。这些目标将增加我们对寒武纪生物地理学以及动物进化中重要时期的性质和拓扑结构的理解。此外，对三个主要的布尔吉斯页岩类型地区进行密集的埋藏学和微地层学研究，将有助于更好地理解控制寒武纪布尔吉斯页岩动物群保存的古环境因素和埋藏学过程，并将有助于我们理解为什么这种类型的保存是寒武纪独有的。由于这些鲜为人知的动物群的丰富性和重要性，研究区域的良好曝光率，以及软体动物群所在的泥岩变质程度相对较低，该项目也提供了一个难得的机会，在相互关联的背景下研究伯吉斯页岩型矿床的系统发育、古生态和保存。一些将被研究的动物群保存在堪萨斯大学(Kansas University)的藏品中，并附有准确的地点数据。还有一位堪萨斯大学的名誉教授迪克·罗宾逊，他在与这笔赠款相关的领域拥有丰富的专业知识。犹他州大学的苏·哈尔格达尔和理查德·贾拉德教授也同意向我们提供他们大量的犹他州寒武纪Burgess页岩型软体动物标本供我们研究；此外，这些资料还附有准确的地点数据。就更广泛的影响而言，该项目将有助于培训两名毕业生，一名在科罗拉多大学，一名在加州大学河滨分校，他们将参与拟议的研究活动并参加科学会议。通过RUI计划，该项目还将帮助波莫纳学院的多名本科生进行实地和分析培训，波莫纳学院是一所仅限本科生的机构，也是凯克地质学联盟的成员。

The study of Cambrian soft-bodied faunas has greatly enhanced our understanding ofsome key events in metazoan evolution. However, enigmas and incompletely describedCambrian Burgess Shale-type soft-bodied faunas still remain, as does the question of why andhow Burgess Shale-type preservation occurs. The immediate objectives of the proposed researchfor which funding is requested are: 1) to prepare, describe, monograph, and fit into aphylogenetic and paleobiogeographic framework new taxa from the Middle Cambrian softbodiedfaunas of the Spence Member and the Wheeler and Marjum Formations using recentcollections made from Utah; 2) to use microanalytical techniques to determine the taphonomy ofthe fossils at the specimen-level; and 3) to place the soft bodied organisms and the taphonomicprocesses involved in their preservation into a detailed paleoenvironmental framework usingnewly developed microstratigraphic techniques.The intellectual merit of this research is to address some enigmas in Cambrianpaleontology and geology, allowing multiple objectives to be attained. First, identifying andcharacterizing the elements of the Utah faunas will help establish which taxa are shared betweenthese formations and other Cambrian soft-bodied faunas distributed throughout the globe. Thus,the stratigraphic and geographic ranges of these species and genera can be determined. Second,in conjunction with pre-existing information, the phylogenetic relationships of the variousarthropods in the Spence, Wheeler, and Marjum can be evaluated. These objectives will increaseour understanding of Cambrian biogeography and also the nature and topology of importantearly episodes in animal evolution. Additionally, intensive taphonomic and microstratigraphicstudy of three of the principal Burgess Shale-type localities will lead to a refined understandingof the paleoenvironmental factors and taphonomic processes that controlled the preservation ofBurgess Shale faunas in the Cambrian, and will contribute to our understanding of why this typeof preservation is unique to the Cambrian. Due to the richness and significance of these poorlyknownfaunas, the excellent exposure across the study areas and the relatively low metamorphicgrade of mudstones hosting the soft-bodied faunas, this project also provides a rare opportunityto address phylogeny, paleoecology, and preservation in Burgess Shale-type deposits in aninterrelated context.Some of the faunas that will be studied are in collections housed at the University ofKansas (KU), and they are accompanied by precise locality data. There is also an emeritusprofessor at the University of Kansas, Dick Robison, with significant expertise in areas related tothis grant. Sue Halgedahl and Richard Jarrard, professors at the University of Utah, have alsoagreed to make their extensive collections of soft-bodied, Cambrian Burgess Shale-type faunasfrom Utah available to us for study; again, these are accompanied by precise locality data. Eachof these factors will greatly facilitate this proposed research.In terms of broader impacts, this project will contribute to the training of two graduatestudents, one at KU and one at the University of California, Riverside, who will participate in theproposed research activities and attend scientific meetings. Through the RUI program, thisproject will also contribute to the field and analytical training of multiple undergraduates fromPomona College, an undergraduate-only institution and member of the Keck geologyconsortium.