Doctoral Dissertation Improvement Grant: Detection and Identification of Maize in Absorbed Pottery Residues: Development and Application

在Nikolaas货车der Merwe博士的指导下，Eleanora Reber女士将为她的博士论文收集数据。她的研究目标是开发一种技术，以确定玉米是否在特定的史前遗址消费。玉米在墨西哥高原被驯化，并在北美和南美的大部分地区传播。今天，它在旧世界和新世界都被广泛种植，是第二大收获作物（仅次于甘蔗）。由于产量与劳动力的关系及其相对可靠性，玉米提供了生存基础，在新大陆的大部分地区，复杂的社会由此产生。考古学家认为，正是以玉米为基础的农业的发展，促成了美国西南部、中西部和东南部的早期文化爆炸。然而，由于大多数考古遗址中的花卉遗迹保存得很差，玉米的证据往往是间接的，科学家不得不依赖于人类骨骼中的微妙化学特征。MS Reber正在开发一种有可能识别烹饪锅上玉米残留物的技术。人种学证据表明，美洲原住民在陶瓷容器中长时间煮玉米，因为粘土是多孔的，它有可能吸收食物残渣。MS Reber将利用气相色谱/质谱仪和气相色谱-燃烧-质谱仪来分析从陶瓷中提取的化学残留物，以寻找玉米信号。将确定具体的化合物，并确定每种化合物的碳同位素比率。在世界上的许多地区，玉米与其他植物相比具有独特的同位素特征，这将提供独特的线索。雷伯女士将首先进行受控实验，在陶瓷容器中烹饪传统的美洲土著玉米品种。然后，这些将被埋在土壤中不同的时间长度，以接近考古学的情况。然后提取残留物并进行分析。在这些结果的基础上，将对该过程进行微调，然后应用于考古标本。最后，雷伯女士将把这项技术应用于一个具体的考古问题。大约在美国中西部出现复杂社会的时候，陶器类型发生了变化，薄壁器皿取代了厚壁器皿。考古学家推测，这一变化与玉米的引入相吻合，薄壁容器更有效地制备玉米炖菜。通过对厚壁和薄壁血管的分析，MS Reber将评估这一假设。这将有助于开发一种技术，如果成功，将适用于世界许多地区的许多考古遗址。这项工作将提供对美国史前史的深入了解，并将有助于培养一位有前途的年轻科学家。

Under the direction of Dr. Nikolaas van der Merwe, MS Eleanora Reber will collect data for her doctoral dissertation. The goal of her research is to develop a technique to determine whether maize was consumed at specific prehistoric sites. Maize was domesticated in highland Mexico and spread through large portions of both North and South America. Today it is widely planted in both the Old and New Worlds and is the second largest harvested crop (after sugar cane). Because of the yield in relation to labor and its relative dependability maize provided the subsistence base from which complex society arose throughout much of the New World. Archaeologists believe that it was the development of maize-based agriculture which underlies the early cultural explosions in the US Southwest, Midwest and Southeast. However because floral remains are poorly preserved in most archaeological sites, often evidence for maize is indirect and scientists have been forced to rely, for example, on subtle chemical signatures in human bone. MS Reber is developing a technique with the potential to identify maize residue on cooking pots. Ethnographic evidence suggests that Native Americans boiled corn for extended periods in ceramic vessels and because clay is porous it has the potential to absorb food residue. MS Reber will utilize both a gas chromatograph/mass spectrometer and gas chromatograph-combustion-mass spectrometry to analyze chemical residue extracted from ceramics to search for a maize signal. Specific chemical compounds will be identified and the carbon isotope ratios of each determined. In many areas of the world maize has a distinctive isotopic signature in relation to other plants and it is this which shall provide the distinctive clue.MS Reber will first conduct controlled experiments in which a traditional variety of Native American maize is cooked in ceramic vessels. These will then be buried in soil for varying lengths of time to approximate archaeological situations. Residues will then be extracted and analyzed. On the basis of these results, the process will be fine-tuned and then applied to archaeological specimens. Finally MS Reber will apply the technique to a specific archaeological question. At approximately the time that complex society arose in the American Midwest, a shift in pottery types took place and thin walled vessels replaced their thick walled counterparts. Archaeologists have postulated that this change coincides with the introduction of maize and that thin walled vessels were more efficient for preparing corn stews. Through analysis of both thick and thin walled vessels, MS Reber will evaluate this hypothesis.This research is important for several reasons. It will help to develop a technique which, if successful, will be applicable in many archaeological sites in many regions of the world. The work will provide insight into the prehistory of the United States and will assist in training a promising young scientist.