Collaborative Research: testing the link between climate and mammalian faunal dynamics in the early Paleocene record of the San Juan Basin, New Mexico

合作研究：在新墨西哥州圣胡安盆地的早期古新世记录中测试气候和哺乳动物动物动态之间的联系，新墨西哥州圣胡安盆地的托马斯·威廉姆森，新墨西哥州自然历史博物馆基金会EAR-1325544Ross Secord，内布拉斯加州大学，林肯，EAR-1325612丹尼尔·佩佩，贝勒大学，EAR-1325552摘要新墨西哥州西北部的纳西米恩托地层包含了世界上已知的最完整、最多样化和最长的早期古新世哺乳动物进化记录，跨度约为6580万年至6220万年。古新世早期对于理解现代生态系统的演化具有特别重要的意义，因为它包括白垩纪末期非鸟类恐龙灭绝后立即出现的第一个以哺乳动物为主的生态系统。这是一个世界比现在更温暖的时期，气候似乎一直不稳定。这项研究将测试气候与古新世早期哺乳动物动物群变化之间的关系，并将更好地理解气候变化在建立最早的哺乳动物主导的生态系统中所起的作用。该项目将通过生成详细的气候记录来测试哺乳动物是否在这一关键时间间隔内对气候变化做出反应，包括通过对化石树叶的叶缘和叶面积分析以及对古代土壤的研究来估计年平均气温和降雨量。这项研究还将使用哺乳动物牙齿的稳定碳同位素重建目前存在的古代生物群和这些生物群中的栖息地，并使用沉积学重建存在的沉积环境类型。这些不同的替代记录将被比较，以检验哺乳动物动物群记录与古新世早期气候变化或生物群变化之间的相关性。这项研究的结果应该有助于开发更准确的模型来预测气候变化的后果。该项目将为高中生、本科生和研究生提供教育和研究机会，包括来自新墨西哥州的美洲原住民学生，他们在科学界的代表性严重不足，以及来自内布拉斯加州的6-8年级“危险”学生。这项研究的结果也将被纳入新墨西哥州自然历史和科学博物馆的永久博物馆展览。

Collaborative Research: Testing the link between climate and mammalianfaunal dynamics in the early Paleocene record of the San Juan Basin, New Mexico byThomas Williamson, New Mexico Museum of Natural History Foundation EAR-1325544Ross Secord, University of Nebraska, Lincoln, EAR-1325612Daniel Peppe, Baylor University, EAR-1325552ABSTRACTThe Nacimiento Formation of northwestern New Mexico contains the most complete, diverse, and longest record of early Paleocene mammal evolution known anywhere in the world, spanning from about 65.8 to 62.2 million years ago. The early Paleocene is of particular importance for understanding the evolution of modern ecosystems because it includes the first mammal-dominated ecosystems that appeared immediately following the end-Cretaceous extinction of non-avian dinosaurs. This was a time when the world was warmer than now and the climate appears to have been unstable. This study will test for a relationship between climate and mammalian faunal change in the early Paleocene, and will provide a better understanding of the role climate change played in the establishment of the earliest mammal-dominated ecosystems. This project will test if mammals responded to climate change during this critical interval of time by generating a detailed climate record, including estimates of mean annual temperature and precipitation from leaf-margin and leaf-area analyses of fossil leaves, and from the study of ancient soils. This study will also reconstruct the ancient biomes present at this time and the habitats within those biomes using stable carbon isotopes from mammal teeth, and the types of depositional environments present using sedimentology. These various proxy records will be compared to test for correlations between the mammalian faunal record and changing climate or changing biomes in the early Paleocene. Results from this study should be useful for developing more accurate models for predicting the consequences of climate change. This project will provide educational and research opportunities for high school, undergraduate, and graduate students, including Native American students from New Mexico, which are greatly underrepresented in the sciences, and "at risk" 6-8th grade students from Nebraska. The results of this research will also be incorporated into a permanent museum exhibit at the New Mexico Museum of Natural History and Science.