Collaborative Research: Integrated Study of an Exceptional Avifauna from the Eocene Green River Formation: New Data on Avian Evolution and Taphonomy

合作研究：始新世绿河地层中一种特殊鸟类的综合研究：鸟类进化和埋藏学的新数据

• 批准号: 0938199
• 负责人: Julia Clarke
• 金额: $ 10.59万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-03 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0938199&HistoricalAwards=false
• 关键词: Collaborative; Research; Integrated; Study; Exceptional

The pattern and timing of the emergence of all living birds remain some of the most contentious questions in vertebrate systematics. Avian fossils are increasingly sought as calibration points for molecular divergence dating and used to test macroevolutionary hypotheses. This project will investigate the best-preserved early Paleogene avian assemblage from North America to forward rapidly our understanding of Cenozoic avian evolution and taphonomy. The assemblage comprises a rich sample of exceptionally preserved, but largely uncharacterized, fossils deposited in less than ~2000 years in distinct, mapped, and sedimentologically characterized sub-environments of a single lake. The deposits are tightly dated to 50.2+-1.9 Mya and occur in the Fossil Butte Member in Wyoming. The project is the first to integrate systematic analyses and an investigation of preservational biases that impact fossil evidence from key lake assemblages. The results are essential to gaining: 1) a global perspective on early Paleogene avian biodiversity; 2) an understanding of the timing and paleobiogeographic patterns of the avian radiation; and 3) answers to fundamental questions of how birds and their feathers are preserved in key lacustrine environments. The results will have wider significance in providing a basis for comparison and indication of likely biases in other assemblages of fossil birds preserved in similar settings such as the Early Cretaceous Jehol Group that yields feathered dinosaurs. The only way to discover what categories of taxa may be systematically missing in such deposits is through the approach proposed here: phylogenetic and taphonomic study of one of the most complete 'snap shots' of avian diversity under the best conditions possible. The broader impacts of the project include novel integration of specimen-based teaching of anatomy, systematic methodologies, and taphonomic approaches; postdoctoral, doctoral and undergraduate training; and the promotion of public understanding of evolution and biodiversity via museum exhibits, linked outreach materials, and lectures.

在脊椎动物系统学中，所有活鸟的出现的模式和时机仍然是一些最有争议的问题。作为分子发散日期的校准点，鸟类化石越来越多地寻求，并用于检验宏观进化的假设。 该项目将调查北美保存最完好的早期古代鸟类组合，以迅速发展我们对新生代鸟类进化和taphonomy的理解。该组合包括丰富的，但在不到2000年的时间内，在一个湖泊的独特，映射和沉积学表征的单个湖中，以不到2000年的时间沉积了化石。这些沉积物的历史可追溯至50.2+-1.9 Mya，并发生在怀俄明州的化石Butte成员中。该项目是第一个整合系统分析的项目，并对影响关键湖泊组合的化石证据的保存偏见进行了调查。结果对于获得至关重要：1）关于早期古纪鸟类生物多样性的全球视角； 2）了解鸟类辐射的时间和古这个地理模式； 3）关于如何保存在关键的湖泊环境中的鸟类及其羽毛的基本问题的答案。该结果将在提供和指示在类似环境中保存的其他化石鸟类（例如早期白垩纪耶霍尔群）中的其他组合中可能偏见的基础上具有更大的意义。在此类沉积物中发现哪些类别可能会系统地缺少哪些类别的分类单元的唯一方法是通过此处提出的方法：在最佳条件下，对鸟类多样性最完整的“快照”的系统发育和taphonomic研究。该项目的更广泛的影响包括基于标本的解剖学教学，系统的方法论和taphonomic方法的新型整合；博士后博士和本科培训；以及通过博物馆展览，链接的外展材料和讲座来促进公众对进化和生物多样性的了解。