Collaborative Research: The Hominid Sites And Paleolakes Drilling Project: Acquiring a High Resolution Paleoenvironmental Context of Human Evolution

了解地球系统过程是否以及如何影响人类进化是一项引起科学家和公众广泛兴趣的挑战。NRC最近的一份报告指出，对支撑人类进化的环境动态的理解已经成熟，可以取得重大进展。这笔赠款将拥有广泛专业知识的科学家聚集在一起，这个团队将扩大古环境数据集，关于环境和人类起源之间关系的假说必须以此为基础。该团队将从埃塞俄比亚和肯尼亚精心挑选的五个古代湖床的长长钻芯中提取岩芯。这些遗址覆盖了新近纪晚期和第四纪的几个重要时期，靠近关键的古人类学遗址，将提供关于古人类聚居地的重要新环境信息。这里申请的资金将用于支持与钻探和初始核心描述相关的运营成本。该项目的目标是从关键人类学遗址附近的沉积物中产生高质量的古环境数据。钻探可以从产生原始人化石的同一层床收集未经改变的样本，这些近乎原始的样本包含可用于破译该地区环境历史的地球化学代理数据。该团队将通过使用玻璃、古地磁和其他直接测年技术，将这些钻芯与附近的海洋记录、包含古人类和其他脊椎动物化石的附近露头记录以及文物组合相关联。来自远古湖床的钻探岩心避免了露头样本问题，如风化、缝隙和不连续的古环境变量表达，同时允许在不同的区间检查季节尺度的环境变异性。该项目将在埃塞俄比亚的北瓦什和周巴希尔盆地以及肯尼亚的西图尔卡纳、巴林戈和马加迪盆地的9个钻孔中收集约2400米的岩心。这些地区产生了一些世界上最重要的古人类化石和文物遗址，直接引发了目前关于人类进化和环境动力学的大部分辩论。所有地点都包含跨越过去400万年大部分时间的长期、连续的气候记录，并且是对一系列环境强迫机制明显敏感的地区。这些岩心将是产生定量古温度、古沉淀和其他环境重建的理想选择，这些环境重建对于理解早期人类经历的环境动力学至关重要。这些数据还将为评估非洲古气候的大、中尺度模型，以及将气候、地形、水文和植被资源联系在一起的模型提供坚实的经验基础，这些模型对早期原始人的生存至关重要。该项目包括为9名美国和非洲学生提供培训机会，包括通过亚利桑那大学的萨加罗项目吸引美国代表性不足的少数族裔本科生的重点外联工作。许多肯尼亚和埃塞俄比亚科学家集中参与了该项目，在该项目的各个阶段将为更多的初级非洲科学家提供培训和研究机会。公共外展活动将通过美国和非洲的三个博物馆合作伙伴进行。过去，当地社区从科学钻探活动中受益，通过将井下套管用作水井。该项目收集的岩心样本和数据将通过国家湖泊核心实验室、ICDP NGDC和史密森人类起源数据库提供给一般科学界。钻探行动将由国际大陆钻探计划共同资助。

Understanding whether and how Earth system processes impacted human evolution is a challenge that generates broad interest among scientists and the general public. A recent NRC report noted how understanding of the environmental dynamics underpinning human evolution is ripe for major advances. This grant brings together scientists with a breadth of expertise, and this team will expand the paleoenvironmental data set upon which hypotheses about the relationship between environment and human origins must be based. The team will recover cores from long drill cores from five carefully selected ancient lake beds in Ethiopia and Kenya. These sites cover several important intervals of the late Neogene and Quaternary, close to key paleoanthropological sites, that will provide important new environmental information about the locales inhabited by ancient hominins. Funding requested here will support operational costs related to drilling and the initial core descriptions.The goal of this project is to produce high-quality paleoenvironmental data from deposits close to key anthropological sites. Drilling allows the collection of unaltered samples from the same beds producing the hominin fossils, These near-pristine samples contain geochemical proxy data that can be used to decipher the region's environmental history. The team will correlate these drill cores to nearby marine records and to nearby outcrop records containing hominin and other vertebrate fossils, and to artifact assemblages by using tephras, paleomagnetism and other direct dating techniques. Drill cores from distal ancient lake beds avoid outcrop sample problems such as weathering, lacunae, and discontinuous expression of paleoenvironmental variables, while allowing examination of seasonal-scale environmental variability in varved intervals. The project will collect ~2400m of cores from nine bore holes at the North Awash and Chew Bahir Basins in Ethiopia, and the West Turkana, Baringo and Magadi Basins in Kenya. These areas have yielded some of the most important fossil hominin and artifact sites in the world, directly stimulating much of the current debate about human evolution and environmental dynamics. All sites contain long, continuous climate records spanning much of the last 4 million years, and are areas which are demonstrably sensitive to a range of environmental forcing mechanisms. The cores will be ideal for generating quantitative paleotemperature, paleoprecipitation, and other environmental reconstructions critical for understanding the environmental dynamics that early hominins experienced. These data will also provide a strong empirical base for evaluating both large and mesoscale models of African paleoclimate, and models linking climate, orography, hydrology and vegetation resources critical for early hominin survival.The project includes training opportunities for nine American and African students, including focused outreach efforts to attract U.S. under-represented minority undergraduates through the University of Arizona's Saguaro Program. Many Kenyan and Ethiopian scientists are centrally involved in the project, and training and research opportunities will exist for more junior African scientists at all stages of the project. Public outreach activities will be carried out through three museum partners in the US and Africa. In the past, the local communities have benefited from scientific drilling activities by casing the boreholes so that they can be used as water wells.Core samples and data collected by this project will be available to the general scientific community through the National Lacustrine Core Laboratory, ICDP NGDC, and the Smithsonian's Human Origins Database. The drilling operations will be co-funded by the International Continental Drilling Programme.