SGER: Scientific Drilling for Human Origins: Exploring the Application of Drill Core Records to Understanding Hominin Evolution

PIS提议调查大陆科学钻探如何被用作了解人类起源的环境背景的工具。这一融合地球科学和古人类学的新研究方向将涉及从位于陆地上的湖床获取沉积物钻探岩心样本，这些湖床靠近对理解人类进化至关重要的区域。他们的努力将集中在过去350万年人类起源的关键时间间隔上。在这一研究的第一阶段，他们将获得肯尼亚和埃塞俄比亚四个关键地点的关键现场勘测和地下数据，这些数据对于未来钻探计划的成功至关重要，该计划将由后来的提案提供资金。他们还要求为一个钻探研讨会提供部分资金，以考虑每个正在考虑的地点带来的技术和科学机遇和挑战。此前，研究人员提出了一个关键问题，即为什么人类及其近亲的进化呈现出一种脉冲式的模式，具有明确定义的广泛物种形成或灭绝、文化变化和地理扩张的时期，并穿插着似乎相对较少变化的长时期。这是定向环境变化(气候等)的广泛强迫效应的结果，是当地或区域环境变化的结果，还是某种尚不清楚的机制的结果。这些努力要么是通过将人类进化模式的大范围模式与深海沉积物岩心连续记录中记录的全球气候变化相关联，要么是通过将化石和考古记录中的区域变化与从古代土壤、湖床和非人化石露头记录推断的更局部的环境变化模式相关联。PIS主张一个新的研究方向，将地球科学界和人类学社区联系起来，解决关于人类起源的这个核心问题，结合上述两种方法的优点，并避免它们固有的一些弱点。他们的计划推动了一项协调一致的努力，从接近于对理解古人类进化至关重要的区域的近连续沉积序列中获得钻探岩心记录，重点放在上面关键问题的关键时间间隔周围。钻探岩芯将提供一种记录，极大地改善对我们近亲各种物种生活的地方和时代的环境历史的了解。从陆地上获得这样的记录将提供比我们目前从深海岩心记录中推断的更详细和更清晰的记录。最后，由于人类进化史上数量最多的关键事件发生在非洲，这样的钻探运动应该从非洲大陆开始。对人类来说，很少有科学问题比了解我们作为一个物种来自哪里，以及我们的环境是如何塑造我们的生物和技术进化更重要的。这一提议的结果将为帮助研究人员解决这些问题的新方向铺平道路，并将促进地球科学/人类学合作的新途径。这一国际钻探计划有重要的科学培训机会，可以让职业生涯早期的美国和非洲科学家参与该项目的各个方面。几名学生将参与研讨会之前的地震现场勘测练习，一些可能在研究生工作中加入该计划的学生将能够参加研讨会。该奖项由美国国家科学基金会国际科学与工程办公室共同资助。

PIs propose to investigate how continental scientific drilling can be used as a tool in understanding the environmental background of human origins. This new research direction in merging earth science and paleoanthropology will involve obtaining sediment drill core samples from lake beds located on-land, close to areas of critical importance for understanding human evolution. Their efforts will be focused around critical time intervals for human origins during the last 3.5 million years. In this first phase of research, they will obtain critical site-survey and subsurface data for four key localities in Kenya and Ethiopia, essential to the success of a future drilling program, to be funded by a later proposal. They also request partial funding for a drilling workshop, to consider the technical and scientific opportunities and challenges posed by each of the sites under consideration.Prior researchers have asked the key question of why evolution of humans and their close relatives displays a pulsed pattern, with well-defined periods of extensive speciation or extinction, cultural change and geographic expansion, interspersed with long periods when relatively little change seems to occur. Is this the result of broad forcing effects of either directional environmental change (climate, etc.), the result of changes in the variability of local or regional environments, or some yet-unrecognized mechanism. These efforts have proceeded either by correlating broad-scale patterns of human evolutionary patterns with the global beat of climate variability as recorded in the continuous records of deep-sea sediment cores or, by correlating regional shifts in the fossil and archaeological record with more local patterns of environmental change, inferred from outcrop records of ancient soils, lake beds and non-hominin fossils. PIs argue for a new research direction linking the earth science and anthropology communities in addressing this central question about human origins, combining the strengths of both of the approaches above, and avoiding some of their inherent weaknesses. Their plan promotes a concerted effort to obtain drill core records from near-continuous sedimentary sequences located close to areas of critical importance for understanding hominin evolution, focused around critical time intervals for their key question above. Drill cores will provide a record that will vastly improve understanding of environmental history in the places and times where various species of our near-relatives lived. Obtaining such records from on land will provide a more detailed and resolved record than what we can currently infer from deep sea core records. Finally, because the largest number of critical events in man's evolutionary history occurred in Africa, such a drilling campaign should start in that continent. Few scientific questions can be more central to humanity than understanding where we have come from as a species, and how our environment has shaped our biological and technological evolution. Results from this proposal will pave the way for a new direction for helping researchers address these questions and will foster a new avenue for earth science/anthropology collaborations. This international drilling program has important science training opportunities for involving early-career American and African scientists in all aspects of the project. Several students will be involved in the seismic site survey exercises leading up to the workshop, and some students who are likely to join the program in post-graduate work would be able to attend the workshop. This award is co-funded by NSF's Office of International Science and Engineering.