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: 1241790
• 负责人: Alan Deino
• 金额: $ 9.97万
• 依托单位: Berkeley Geochronology Center
• 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=1241790&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.

非洲人类进化在过去几百万年里受到地球气候和环境历史的强烈影响的可能性一直是古人类学研究前沿的一个重要问题。一个基本问题是：是否可以足够精确地重建进化变化的任何潜在环境驱动因素，使我们能够自信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，从而及时检验它们之间的关系。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，通过收集和分析详细的古环境数据，对连接环境历史和哺乳动物（包括早期人类）进化的关键假设进行直接检验。非洲三个主要人类学地点的数据。他们将通过从埃塞俄比亚阿法尔北部（约3.8-290万年前-Ma）、肯尼亚巴林戈盆地（约3.2-2.35 Ma）和图尔卡纳盆地的古代湖床钻取长沉积岩芯来收集连续的古环境记录，肯尼亚（~2.3-1.42 Ma），并将这些记录与同一盆地中的露头联系起来，这些盆地中包含早期人类和其他哺乳动物化石，以及较年轻的石器时间段。作为一个整体，这些盆地包含了非洲人类进化史的一些最重要的证据。尽管过去的研究人员已经根据发现人类化石和文物的露头重建了气候和其他环境历史，但由于化石所在沉积物的性质，此类环境记录高度不连续，并且不适合许多最重要的环境记录。由于风化作用影响了露头的沉积物，今天可以获得信息丰富的地球化学记录。在化石遗址附近钻探湖床可以解决这些问题，因为湖泊沉积物的积累更加连续，而且钻入地下可以收集未风化的样本 该项目的钻探费用已从其他来源获得：IPG 资金该团队将对岩心进行分析，以生成温度、降水、植被、火灾和火山活动以及其他可能影响人类进化的因素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长岩心，每个盆地都有长岩心。其中跨越了人类进化的关键时期，并且接近古人类化石和考古遗址。研究人员将对这些岩心应用最先进的古环境和古气候方法，以收集涵盖东非过去四百万年环境历史大部分内容的高分辨率记录。然后，该团队将评估现有的假设，并产生新的假设，将气候历史与早期人类的身体和文化进化适应联系起来。通过岩芯和露头中存在的大量火山灰以及其他年代测定技术，从钻芯收集的古环境和古生态数据将在时间和空间上与附近的人类、哺乳动物和石器化石记录直接联系起来。通过将新记录与附近海洋沉积物核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本地驱动因素和全球驱动因素，并在此过程中测试一系列将人类进化中的关键事件与气候和环境历史其他方面联系起来的假设。最后，该团队将使用这些新的、组合的古环境和古人类学数据集，结合新颖的建模技术，更好地了解不同时间和空间尺度的景观和气候变化可能如何影响关键生态系统资源的可用性和可预测性，并据此进行早期预测。人类会依赖。该项目将极大地扩展我们对非洲气候历史的了解，并将成为激发美国和非洲公众对人类进化及其与气候关系的兴趣的机会。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大量非正式的科学学习机会。