Doctoral Dissertation Improvement Award: The Ecological Context of Modern Human Adaptability

这篇博士论文研究了第四纪晚期现代人类进化的生态背景。这一点很重要，因为理解人类物种特有行为的进化，如增强适应灵活性和社会互动和交流网络的扩展等，关键在于跟踪它们在深层次上的轨迹。到目前为止，适应灵活性的考古证据主要来自大约13万到3万年前的中石器时代后半段(MSA)的遗址。然而，正在研究的地点有几个层次分明的MSA序列，为追踪现代人类进化叙事中心区域的长期环境变化和生物文化反应提供了极好的机会。这项工作为进一步的特定地点、高分辨率的古环境重建奠定了基础，并提供了关于环境变化是否以及如何在人类行为进化期间促进创新的知识。它进一步评估了测距模式和环境变化之间的联系。调查人员还利用该项目对来自当地大学的感兴趣的学生进行考古领域和实验室方法的培训。该项目涉及的问题是，审议中遗址的场地一级环境重建是否与第四纪晚期记录的当地气候和古环境模式相匹配。他们还在确定干旱和潮湿时期的距离模式和社会联系程度是否有所不同。最后，他们正在调查，随着时间的推移，岩屑技术的变化是否意味着对环境变化的反应越来越熟练。为了实现这一点，挖掘了四个MSA遗址，发现了数千件石器文物。记录了各种岩屑技术属性，目前正在通过火山灰的化学指纹和40Ar/39Ar测年来建立该地区的年代地层史。该项目的这一阶段正在开发高分辨率的古环境重建，使用植物叶蜡(δ13C蜡)、大量有机物(δ13COM)和碳酸盐结核，以及使用便携式手持式X射线荧光(PXRF)机器寻找黑铁矿文物。这一奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

xThis doctoral dissertation project investigates the ecological context of modern human evolution during the Late Quaternary. This is important because the key to understanding the evolution of behaviors characteristic of the human species, such as enhanced adaptive flexibility and the expansion of social interaction and exchange networks, among others, lies in tracking their trajectories through deep time. To date, archaeological evidence for adaptive flexibility comes mainly from sites dating to the latter half of the Middle Stone Age (MSA) from ca. 130,000 to 30,000 years ago.. However, the sites under study has several well-stratified MSA sequences that offer an excellent opportunity to track longer-term environmental changes and biocultural responses in a region central to the modern human evolution narrative. This work sets the context for further site-specific, high-resolution paleoenvironmental reconstructions and contributes knowledge on whether and how environmental changes precipitated innovation during the behavioral evolution of humans. It further assesses the connection between ranging patterns and environmental changes. The investigators also use the project to train interested students from local universities in archaeological field and lab methods. The project addresses questions as to whether site-level environmental reconstructions in the sites under consideration match local climatic and paleoenvironmental patterns recorded for the Late Quaternary. They are also determining if ranging patterns and degree of social connectivity differ during arid versus humid periods. Lastly, they are investigating whether lithic technological shifts through deep time suggest increasingly adept responses to environmental change. To achieve this, four MSA sites were excavated resulting in thousands of lithic artifacts. Various lithic technological attributes were recorded, and work is underway to develop a chronostratigraphic history of the region through chemical fingerprinting of the volcanic ashes and 40Ar/39Ar dating. This phase of the project is developing a high-resolution paleoenvironmental reconstruction using plant leaf waxes (δ13Cwax), bulk organic matter (δ13COM), and carbonate nodules, as well as at sourcing obsidian artifacts using a portable handheld X-ray fluorescence (pXRF) machine.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.