NSF Dissertation Improvement Grant: Assessing Seasonal Mobility in Prehistory: An Isotopic Perspective from the St. Johns River Basin, Florida

在John Krigbaum博士的指导下，Bryan Tucker将分析佛罗里达州东北部古时期(约10,000至3,000年前)考古遗址中发现的人类牙齿的稳定碳和氧同位素比率。从人类学到动物学，生物组织中光稳定同位素比率(如13C/12C和18O/16O)的分析已经改变了研究的进行方式和研究问题的类型。在考古学中，经常通过挖掘发现的骨骼和牙齿可以产生稳定的碳和氧同位素比率，反映过去生态、饮食和气候的变化。这种方法现在已经确立，并提供了一种强有力的手段，可以独立地证实从考古记录中推断出的其他证据。北美东南部的古老时期以狩猎-采集人口为特征，他们居住在各种不同的生态区，饮食制度多样化，随季节变化。然而，这一时期的大多数考古遗址都是停尸丘遗址，而不是居住地。在此期间，一些群体变得越来越久坐不动，然而，他们何时何地获得食物仍然是一个悬而未决的问题。塔克的工作将开发稳定同位素分析的新方法，以推断人类饮食和生态的季节性变化，从而建立史前人类的活动模式。稳定同位素分析继续取得进展，特别是在分析的空间和时间分辨率方面。这篇论文的研究将建立在改进的牙齿同位素采样的基础上，分别使用稳定的碳和氧同位素提供每半年一次的、季节性的饮食和生态记录。具体地说，塔克将把重点放在牙釉质的增量生长线上，这些线在人类牙列中像发条一样形成。在牙釉质沉积期间的特定时间采样的同位素比率将反映该个体在牙齿形成期间的饮食和生态。通过对牙釉质薄片的分析和采样，将获得更准确的记录，从而可以推断每个采样的古代个体的季节性生态和文化条件。这一跨学科研究将对区域史前研究和稳定同位素分析方法作出实质性贡献。与考古学同事的合作、在同行评议的期刊和通讯上发表文章、公开介绍以及在网上出现，都将提供一种手段，向科学界和广大公众宣传这项研究的成果。此外，对本科生的培训将培养他们对这些重要的突破性技术的兴趣。

Under the direction of Dr. John Krigbaum, Bryan Tucker will analyze stable carbon and oxygen isotope ratios from human teeth recovered from Archaic period (ca. 10,000 to 3,000 years ago) archaeological sites in northeastern Florida. From anthropology to zoology, analysis of light stable isotope ratios (e.g., 13C/12C and 18O/16O) in biological tissues has transformed how research is conducted and the types of research problems addressed. In archaeology, the bones and teeth that are frequently recovered through excavation can yield stable carbon and oxygen isotope ratios that reflect past changes in ecology, diet and climate. Such methods are now well-established and provide a robust means to independently corroborate other lines of evidence inferred from the archaeological record. The Archaic period in southeastern North America is characterized by hunter-gatherer populations who inhabited a variety of different ecological zones with a diverse dietary regime that varied seasonally. Most of the archaeological sites that characterize this period, however, are mortuary mound sites rather than habitation sites. Over the course of this period, some groups became increasingly sedentary, however, when and where they procured their food remains an open question. Tucker's work will develop new methods in stable isotope analysis to infer seasonal changes in human diet and ecology, thereby establishing human mobility patterns in prehistory.Advances continue to be made in stable isotope analysis, particularly with respect to the spatial and temporal resolution of the analysis. This dissertation research will build on improvements in the isotopic sampling of teeth to provide a subannual, seasonal record of diet and ecology using stable carbon and oxygen isotopes, respectively. Specifically, Tucker will focus on the incremental growth lines of tooth enamel that form like clockwork in the human dentition. The isotopic ratios sampled at a given time during tooth enamel deposition will reflect the diet and ecology of that individual during the time of that tooth's formation. Through the analysis and sampling of tooth enamel in thin section, a more accurate record will be sampled that will allow seasonal ecological and cultural conditions to be inferred for each Archaic individual sampled. This interdisciplinary research will contribute substantively to studies of regional prehistory and to methods employed in stable isotope analysis. Collaboration with archaeology colleagues, and publication in peer-reviewed journals and newsletters, public presentations and a presence on the web will all provide a means to communicate the findings of this research to the scientific community and the public at large. Further, the training of undergraduate students will foster their interests into these important and ground-breaking techniques.