Collaborative Research: Climatic and Biotic Transformations of Neogene Mammalian Faunas of Pakistan

合作研究：巴基斯坦新近纪哺乳动物区系的气候和生物转变- Catherine Badgley，密歇根大学，安阿伯，MIThure Cerling，犹他州大学，湖城，UT，大卫Pilbeam，哈佛大学，剑桥，MA摘要来自四个机构的合作者将讨论巴基斯坦中新世化石记录中哺乳动物对全球气候，海平面，构造障碍，移民物种。西瓦利克记录包括从巴基斯坦到缅甸的喜马拉雅前陆盆地中沉积的高含铝新近纪沉积物。在巴基斯坦的Potwar高原，这一记录提供了过去1 800万年连续地层序列中动物群和环境变化的无与伦比的历史。在这段时间内，哺乳动物古群落表现出不断变化的混合物的世界性群体，地方性血统，和孑遗类群。从深海岩芯和其他地质证据中可以了解到可能驱动这些动物群变化的环境过程。这些过程发生在不同的地理尺度上，从全球气候系统和海平面到区域（南亚）构造运动，再到当地的洪泛盆地及其植被和当地气候。拟议的分析将通过以下方式检验环境过程与生物反应之间的关系：（1）评估1800万至550万年前不同地球动力学和气候条件下哺乳动物区系的变化;（2）综合西瓦利克记录中古气候变化的多种指标，包括利用氧化铁估算土壤湿度的新地球化学方法，来自蜗牛盖的关于降水季节性的信息，来自牙釉质和土壤碳酸盐的稳定同位素，以及使用功能形态学测量已灭绝哺乳动物的饮食和体型。

Collaborative Research: Climatic and Biotic Transformations of Neogene Mammalian Faunas of Pakistan - Catherine Badgley, University of Michigan, Ann Arbor, MIThure Cerling, University of Utah, Salt Lake City, UT, David Pilbeam, Harvard University, Cambridge, MAAbstractCollaborators from four institutions will address the ecological and evolutionary responses of mammals from the Miocene fossil record of Pakistan to changes in global climate, sea level, tectonic barriers, and immigrant species. The Siwalik record consists of highly fossiliferous Neogene sediments deposited in the Himalayan foreland basin from Pakistan to Myanmar. In the Potwar Plateau of Pakistan, this record provides an unparalleled history of faunal and environmental change in a continuous sequence of strata spanning the last 18 million years. During this time period, mammalian paleocommunities exhibited a changing mixture of cosmopolitan groups, endemic lineages, and relict taxa. Environmental processes that may have driven these faunal changes are known from deep-sea cores and other geological evidence. These processes occurred at different biogeographic scales, ranging from those of the global climate system and sea level to regional (South Asian) tectonism to the local floodbasin and its vegetation and local climate. The proposed analyses will test the relationship between environmental processes and biological responses by (1) evaluating mammalian faunal change under different geodynamic and climatic conditions over the interval between 18.0 and 5.5 million years ago, and (2) integrating multiple indicators of changing paleoclimate from the Siwalik record, including a new geochemical method for estimating soil moisture using iron oxides, information from snail opercula about seasonality of precipitation, stable isotopes from tooth enamel and soil carbonate, and measures of diet and body size for extinct mammals using functional morphology.