Doctoral Dissertation Research: Establishing contexts of encounters: Radiocarbon dating of archaeological assemblages with implications for Neanderthal-modern human interactions

在大卫·皮尔比姆博士的指导下，博士生布里奇特·亚历克斯将改进基于放射性碳的现代人和尼安德特人在人口之间潜在接触的三个地区的分布年表。修订后的年表将有助于限制它们重叠的地点和时间。在这样的背景下，可以比较这两个群体的考古记录，以确定有意义的差异，并可能识别现代人独有的适应。这种比较是解决人类学一个基本问题的一种方法：现代人有什么独特之处？为什么其他人类种群灭绝了？绘制尼安德特人和现代人在时间和空间上的分布是有问题的。根本的问题是如何证明可测年材料(主要是有机碳)与特定人类群体的存在有关。已经开发了一些理论和方法创新，以支持放射性碳年代和人口发生之间的联系。首先，由于缺乏在分类学上明确的、直接确定年代的人类化石，大多数种群的出现都是根据考古学的代理来推断的。为了对考古种群进行分类，学者们已经从以人工制品为基础的类型学转向广泛的行为包，或物质文化生产中特定于文化的一套特殊选择。其次，生产可靠的放射性碳测年需要对背景、挖掘历史和潜在样品的保存进行严格的评估。这一过程的关键是将实地工作和实验室分析结合起来，以便同一调查员能够记录样本挖掘后的完整历史，并更好地解释异常情况。最后，放射性碳样品应该通过旨在去除污染物的最先进的前处理程序来制备。Alex将合成这些创新，以产生可靠的放射性碳数据，用于在三个潜在重叠区域的活跃挖掘：黎凡特的马诺洞、巴尔干的佩图里纳洞穴和东北欧的西姆纳洞穴。新的日期将与经过严格审查的公布日期相结合，以产生安全的区域年表，这些年表可用于评估每个地区尼安德特人与现代人类互动的可能性。该项目将提供一个研究框架和关键数据，与人类学中最具争议性的主题之一有关：现代人类灭绝、尼安德特人灭绝和50-30公里之间的文化变化之间的关系。该项目旨在产生广泛的、期望的社会影响。它需要并将促进不同领域的学者之间的国际合作，包括考古学、生物人类学、地球科学和化学。亚历克斯将从不同的角度接受科学家的指导，并将这种培训传播给国内外的学生。这些方法和结果将通过亚历克斯积极参与的各种外展组织与公众分享。这些组织包括哈佛自然历史博物馆和皮博迪博物馆，以及女孩科学俱乐部，这是一个为女孩和少数族裔提供科学体验的项目。最后，尼安德特人与现代人类互动的话题引起了公众的广泛兴趣。亚历克斯定期就这一主题举行公开讲座，这是教育公众科学方法、进化论和气候变化的绝佳机会。

Supervised by Dr. David Pilbeam, doctoral candidate Bridget Alex will produce improved radiocarbon-based chronologies of modern human and Neanderthal distributions in three regions of potential contact between the populations. The revised chronologies will help to constrain where and when they overlapped. In such a context the archaeological records of both groups can be compared in order to identify meaningful differences and possibly, adaptations unique to modern humans. This comparison is one approach to a fundamental question of anthropology: what is unique about modern humans and why did other human populations go extinct?Mapping the distribution of Neanderthals and modern humans in time and space is problematic. The underlying issue is how to demonstrate that dateable material (mainly organic carbon) relates to the presence of a particular human population. A number of theoretical and methodological innovations have been developed to support the links between radiocarbon dates and population occurrences. First, due to the paucity of taxonomically unambiguous, directly dated human fossils, most population occurrences are inferred from archaeological proxies. To classify archaeological populations, scholars have shifted from artifact-based typologies to broad behavioral packages, or culturally specific suites of idiosyncratic choices in the production of material culture. Next, the production of reliable radiocarbon dates requires rigorous evaluation of the context, taphonomic history, and preservation of potential samples. Essential to this process is an integration of fieldwork and laboratory analyses, so that the same investigator can document the full post-excavation history of samples, and better explain anomalies. Lastly, radiocarbon samples should be prepared by state of the art pretreatment procedures designed to remove contaminants.Alex will synthesize these innovations to produce reliable radiocarbon dates for active excavations in three regions of potential overlap: Manot Cave in the Levant, Pe'turina Cave in the Balkans, and Ciemna Cave in Northeast Europe. The new dates will be combined with critically reviewed published dates to produce secure regional chronologies, which can be used to evaluate the likelihood of Neanderthal-modern human interactions in each region. The project will provide a research framework and critical data pertinent to one of the most debated topics in anthropology: the relations between modern human dispersals, Neanderthal extinctions, and cultural changes between 50-30 ka.The project aims to impart broad, desired societal impacts. It requires and will facilitate international collaboration between scholars in different fields, including archaeology, biological anthropology, earth sciences, and chemistry. Alex will be mentored by scientists from diverse perspectives, and will disseminate this training to students at home and abroad. The methods and results will be shared with the public through a variety of outreach organizations, with which Alex is actively involved. The organizations include the Harvard Museum of Natural History and Peabody Museum, as well as Science Club for Girls, a program that provides science experiences to girls and minorities. Lastly, the topic of Neanderthal-modern human interactions enjoys widespread public interest. Alex regularly offers public lectures on the topic, which are excellent opportunities to educate the public on the scientific method, evolution, and climate change.