FESD Type I: Earth System Dynamics and its Role in Human Evolution in Africa

该项目将收集和分析肯尼亚和埃塞俄比亚关键地区的湖泊沉积物钻探岩心记录，以极大地提高我们对人类进化的古环境和古气候背景的理解。理解气候/环境历史和人类进化之间的关系是一个具有广泛科学和公众利益的持久挑战。关键问题包括：在人类进化的关键时期，气候和构造变化是如何相互作用的？是什么过程在地方到区域的尺度上规范了这段历史？当地的气候变化记录是否反映了全球变化？气候和构造过程是如何以及何时结合在一起影响早期人类栖息地、资源和人口结构的？这些不断变化的情况是否与人类谱系中的进化过程和事件有关？对这种关系的研究涉及地球科学、环境科学和人类学。我们将从湖泊沉积物中收集的沉积物钻探岩心将提供详细的、高分辨率的环境历史记录。通过数据收集和建模，我们的目标是从根本上改变关于全球、区域和地方尺度的环境动态可能如何塑造人类进化史的争论。该项目将通过在埃塞俄比亚(北瓦瓦什河和周巴希尔地区)和肯尼亚(图尔卡纳西部、图根山和肯尼亚南部马加迪河裂谷/马加迪湖)的五个高度优先地区钻探长岩心来获得连续的古环境记录，在这些地区，可以通过包含化石和文物的相同盆地中的重要时间间隔收集高分辨率、连续的湖泊古气候记录。我们没有假设环境历史和进化之间的联系，而是将这项研究设计为一系列数据收集和建模练习，以明确测试关于环境和进化动力学的总体和局部假设。我们的高分辨率(百年-千年尺度)和可确定日期的地球化学、古生态和沉积学记录将使我们能够在区域尺度上定量重建古沉淀、古温度、古水文和地貌演化。我们将使用高分辨率的地层学、磁性地层学和其他地质年代学技术将这些记录与包含人和其他脊椎动物化石和人工制品的邻近暴露以及附近的海洋记录相关联。我们将开发预测人类进化关键时期环境变化和生态系统响应的数值模型，并根据我们新的高分辨率记录对这些模型进行评估。这些实验将研究跨越时间和空间尺度等级的景观和气候变化如何影响关键生态系统资源的持久性和可预测性。它们将使我们能够评估气候阈值和突然的环境变化的重要性，并更好地理解可能塑造了人类进化记录的地球系统动力学。我们的模型将产生关于人类进化/地球系统动力学的新的、可测试的假说，包括从进化的原始人种群向其环境的可能反馈。我们的项目将创建一个关键数据集，用于解决基本的、关乎人类生存的问题。我们将为16名美国研究生、2名博士后和10名本科生提供培训和实习机会，并在项目实地和初始核心描述阶段为非洲学生和专业参与者提供大量培训机会。我们还计划在非正规教育方面进行大量投资，通过3D视频项目和外联活动，我们将在钻探阶段期间和之后与我们的三个博物馆合作伙伴(史密森学会、肯尼亚和埃塞俄比亚国家博物馆)协调。

This project will collect and analyze lake sediment drill core records from key localities in Kenya and Ethiopia to vastly improve our understanding of the paleoenvironmental and paleoclimatic context of human evolution. Understanding the relationship between climate/environmental history and human evolution is an enduring challenge of broad scientific and public interest. Key questions include: How did climate and tectonic change interact during critical intervals of human evolution? What processes regulated this history on local to regional scales? Do local records of climate change reflect global changes? How and when did climatic and tectonic processes combine to influence early human habitats, resources, and demography? Were these changing conditions related to evolutionary processes and events in the human lineage? Research on this relationship cuts across Earth, environmental and anthropological sciences. The sediment drill cores we will collect from lake deposits will provide detailed and highly resolved records of environmental history. Through data collection and modeling we aim to fundamentally transform the debate concerning how environmental dynamics at global, regional and local scales may have shaped human evolutionary history.The project will obtain continuous paleoenvironmental records by drilling long cores from five high-priority areas in Ethiopia (N. Awash River and Chew Bahir areas) and Kenya (W. Turkana, Tugen Hills and southern Kenya Rift/Lake Magadi) where highly-resolved, continuous lacustrine paleoclimate records can be collected through important time intervals in the same basins that contain fossils and artifacts. Rather than assume a linkage between environmental history and evolution, we designed this study as a series of data collection and modeling exercises to explicitly test overarching and local hypotheses about environmental and evolutionary dynamics. Our high-resolution (centennial-millennial scale) and datable geochemical, paleoecological and sedimentological records will allow quantitative reconstruction of paleoprecipitation, paleotemperature, paleohydrology and geomorphic evolution at a regional scale. We will correlate these records using high-resolution tephrostratigraphy, magnetostratigraphy and other geochronological techniques to adjacent exposures that contain hominin and other vertebrate fossils, and artifacts, as well as to nearby marine records. We will develop predictive numerical models of environmental change and ecosystem response during critical intervals of human evolution and evaluate these models against our new, high-resolution records. These experiments will examine how landscape and climate change across a hierarchy of temporal and spatial scales impacts the durability and predictability of critical ecosystem resources. They will allow us to evaluate the importance of climatic thresholds and abrupt environmental changes and better understand the earth system dynamics that might have shaped the record of human evolution. Our modeling will generate new, testable hypotheses of human evolution/Earth system dynamics, including possible feedbacks from evolving hominin populations to their environments. Our project will create a key data set for addressing fundamental, existential questions for humanity. We will provide training and internship opportunities for 16 American graduate students, 2 post-docs and 10 undergraduates, and numerous training opportunities for African student and professional participants during the field and initial core description phase of the project. We have also planned significant investment in informal education, through a 3-D video project and outreach activities we will coordinate with our three museum partners (Smithsonian Institution, National Museums of Kenya and Ethiopia), both during and following the drilling phase.