IPG: Collaborative Research: A high-resolution analysis of unique paleoenvironmental data from key hominin sites in East Africa

IPG：合作研究：对东非主要古人类遗址的独特古环境数据进行高分辨率分析

• 批准号: 1241615
• 负责人: Craig Feibel
• 金额: $ 8.54万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-10-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1241615&HistoricalAwards=false
• 关键词: IPG; Collaborative; Research; resolution; analysis

The possibility that human evolution in Africa has been strongly influenced by Earth's climatic and environmental history over the last several million years has been an important question at the forefront of paleoanthropological research. One fundamental question is: can any of the potential envionmental drivers of evolutionary change be reconstructed with enough precision to allow us to relate them with confidence to the episodes of speciation, extinction and cultural evolution known to anthropologists, and thereby test their relationships in time and space?This team of paleoanthropologists and earth scientists plans to analyze climate and other environmental histories to provide direct tests of key hypotheses linking environmental history and mammal (including early human) evolution by collecting and analyzing detailed paleoenvironmental data at three key anthropological sites in Africa. They will collect continuous paleoenvironmental records by drilling long sediment cores from ancient lake beds in the northern Afar, Ethiopia (~3.8-2.9 million years ago-Ma), the Baringo Basin, Kenya (~3.2-2.35 Ma), and the Turkana Basin, Kenya (~2.3-1.42 Ma), and relate these records to the outcrops in the same basins that contain early human and other mammal fossils, as well as stone tools in the younger time periods. As a group these basins contain some of the most critical evidence for human evolutionary history in Africa. Although past investigators have reconstructed climate and other environmental histories from the outcrops in which the fossil humans and artifacts have been found, such environmental records are highly discontinuous due to the nature of the sediments where the fossils occur, and are unsuitable for many of the most informative geochemical records available today because of the weathering that has affected outcropping sediments. Drilling lakebeds near the fossil sites gets around these problems, because lake sediments accumulate much more continuously, and because drilling into the subsurface allows unweathered samples to be collected Funding for the drilling costs for this project has been secured from other sources: with the IPG funds the team will analyze the cores to generate quantitative and high resolution records of changes in temperature, precipitation, vegetation, fire and volcanic activity and other factors which may have influenced human evolution.The primary research goal is to obtain long cores from these basins, each of which span critical intervals in human evolution and are close to hominin fossil and archaeological sites. The researchers will apply state-of-the-art paleoenvironmental and paleoclimate methods to these cores to assemble high resolution records covering much of the past four million years of East African environmental history. The team will then evaluate existing hypotheses and generate new hypotheses linking climate history to early human physical and cultural evolutionary adaptations. The paleoenvironmental and paleoecological data collected from the drill cores will be linked directly in time and space to the nearby fossil human, mammal and stone tool records by way of the numerous volcanic ashes present in both the cores and outcrops, along with other dating techniques. By comparing the new records to similar records from nearby ocean sediment cores the researchers plan be able to distinguish local from global drivers of environmental change and in the process test a series of hypotheses linking key events in human evolution with climate and other aspects of environmental history. Finally, the team will use these new, combined paleoenvironmental and paleoanthropological data sets, combined with novel modeling techniques to better understand how landscape and climate change across various scales of time and space may have affected the availability and predictability of critical ecosystem resources upon which early humans would have depended. This project will greatly expand our understanding of African climate history and will be an opportunity to invigorate interest in human evolution and its relationship to climate with the US and African public. The project will train many American and African students during its field, analytical and internship/synthesis phases, and will generate numerous informal science learning opportunities through our collaborations with the National Museums of Kenya and Ethiopia and the Smithsonian Institution.

过去几百万年来，非洲的人类进化可能受到地球气候和环境历史的强烈影响，这是古人类学研究前沿的一个重要问题。一个根本的问题是：能否以足够的精度重建进化变化的潜在环境驱动因素，使我们能够有把握地将它们与人类学家已知的物种形成、灭绝和文化进化事件联系起来，从而测试它们在时间和空间上的关系？这个由古人类学家和地球科学家组成的团队计划分析气候和其他环境历史，通过收集和分析非洲三个关键人类学地点的详细古环境数据，直接测试将环境历史和哺乳动物(包括早期人类)进化联系起来的关键假说。他们将通过在埃塞俄比亚阿法尔北部(约380万-290万年前)、肯尼亚巴林戈盆地(约3.2-2.35 Ma)和肯尼亚图尔卡纳盆地(约2.3-1.42 Ma)的古老湖床中钻探长沉积岩心，收集连续的古环境记录，并将这些记录与同一盆地中的露头相关联，这些盆地包含早期人类和其他哺乳动物化石，以及年轻时期的石器工具。作为一个整体，这些盆地包含了非洲人类进化史的一些最关键的证据。尽管过去的研究人员已经从发现化石和文物的露头恢复了气候和其他环境历史，但由于化石所在沉积物的性质，这样的环境记录是高度不连续的，而且由于风化作用影响了露头沉积物，因此不适合于今天可用的许多最有信息量的地球化学记录。在化石遗址附近钻探湖床可以绕过这些问题，因为湖泊沉积物的积累要持续得多，而且因为向地下钻探可以收集未风化的样本，所以这个项目的钻探成本已经从其他来源获得了资金：利用IPG的资金，研究小组将分析岩心，以生成温度、降水、植被、火和火山活动以及其他可能影响人类进化的因素的变化的定量和高分辨率记录。主要研究目标是从这些盆地中获得较长的岩心，每个盆地跨越人类进化的关键时间间隔，并且接近化石和考古遗址中的古人类。研究人员将把最先进的古环境和古气候方法应用于这些岩芯，以收集涵盖东非过去400万年环境历史大部分时间的高分辨率记录。然后，该团队将评估现有的假说，并产生将气候历史与人类早期身体和文化进化适应联系起来的新假说。从钻探岩心收集的古环境和古生态数据将通过岩心和露头中存在的大量火山灰以及其他测年技术，在时间和空间上直接与附近的人类、哺乳动物和石器化石记录联系起来。通过将新记录与附近海洋沉积物岩心的类似记录进行比较，研究人员计划能够区分环境变化的局部和全球驱动因素，并在这个过程中测试一系列假设，将人类进化中的关键事件与气候和环境历史的其他方面联系起来。最后，该团队将使用这些新的、结合了古环境和古人类学的数据集，结合新的建模技术，更好地理解不同时间和空间尺度上的景观和气候变化可能如何影响早期人类赖以生存的关键生态系统资源的可用性和可预测性。该项目将极大地扩大我们对非洲气候历史的了解，并将成为一个机会，激发美国和非洲公众对人类进化及其与气候的关系的兴趣。该项目将在实地、分析和实习/综合阶段培训许多美国和非洲学生，并将通过我们与肯尼亚和埃塞俄比亚国家博物馆以及史密森学会的合作，创造许多非正式的科学学习机会。