DISSERTATION RESEARCH: Mammalian Distribution in the Late Cretaceous and Earliest Paleocene Western Interior of North America: Testing Provinciality Through Time

论文研究：晚白垩世和最早古新世北美西部内陆的哺乳动物分布：随着时间的推移检验省域性

• 批准号: 9622771
• 负责人: William Clemens
• 金额: $ 0.31万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-06-15 至 1998-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9622771&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Mammalian; Distribution; Late

9622771 CLEMENS Floodplain and delta sediments of Late Cretaceous to earliest Paleocene (Tertiary) age (72-60 Million Years Ago), laid down as the Western Interior Seaway retreated across the North American continent, document an extraordinary period of mammalian evolution. Mammals survived and rapidly diversified across the Cretaceous-Tertiary (K/T) boundary (66 MYA); many other groups of animals suffered mass extinctions at this boundary. Many questions in the fields of evolutionary biology, paleoecology and biostratigraphy can be addressed through an understanding of the patterns of mammalian distribution during this time period. Recent studies of fossil mammals preserved in these floodplain sediments indicate that during the Late Campanian (approximately 72 MYA) there were distinct northern and southern faunas. Did these faunas remain distinct in the 12-million year period following? If not, in what respects did they change? It has been difficult to identify basic patterns, partly because of the large and scattered amount of geographic information, and partly because the relationships among the animals in question are poorly understood. Newly available computational tools will allow Anne Wiel, under the supervision of William Clemens, to address these questions quantitatively for the first time. The first stage of the research will address questions of the phylogenetic relationships among the species of mammals identified in the fossil remains, including those among species that have not previously been considered. New hypotheses are to be incorporated in a database compiled from fossil site data from throughout the Western Interior. Using a Geographic Information System (GIS) to recognize spatial associations in this geographic, environmental, and taxonomic data, the investigators will apply different types of analyses commonly used to quantify faunal similarity or variation, and compare the results. This project will benefit the scientific community in three ways: by cre ating a database that will be made available to other researchers; by comparing different measures of faunal similarity; by creating a robust, testable, and accessible model of mammalian distribution across the K/T boundary.

9622771 克莱门斯河漫滩和三角洲沉积物从白垩纪晚期到最早的古新世（第三纪）时代（72-6000 万年前），是随着西部内海航道撤退穿过北美大陆而形成的，记录了哺乳动物进化的一个非凡时期。 哺乳动物在白垩纪-第三纪 (K/T) 边界上幸存下来并迅速多样化 (66 MYA)；许多其他动物群体在这个边界遭受了大规模灭绝。 通过了解这一时期哺乳动物的分布模式，可以解决进化生物学、古生态学和生物地层学领域的许多问题。 最近对这些洪泛区沉积物中保存的哺乳动物化石的研究表明，在坎帕阶晚期（大约 72 MYA）期间，存在着明显的北部和南部动物群。 这些动物群在接下来的 1200 万年里仍然保持独特吗？ 如果没有，他们在哪些方面发生了变化？ 识别基本模式一直很困难，部分原因是地理信息量大且分散，部分原因是人们对相关动物之间的关系知之甚少。 新推出的计算工具将使 Anne Wiel 在 William Clemens 的监督下首次定量地解决这些问题。 研究的第一阶段将解决化石遗骸中发现的哺乳动物物种之间的系统发育关系问题，包括以前未考虑过的物种之间的系统发育关系。 新的假设将被纳入根据整个西部内陆化石遗址数据汇编而成的数据库中。 研究人员将使用地理信息系统（GIS）来识别地理、环境和分类数据中的空间关联，并应用通常用于量化动物区系相似性或变异的不同类型的分析，并比较结果。 该项目将以三种方式使科学界受益：创建可供其他研究人员使用的数据库； 通过比较动物区系相似性的不同衡量标准；通过创建一个强大的、可测试的、可访问的跨 K/T 边界的哺乳动物分布模型。