Seasonality Determinations from Archaeological Oyster Shells: An Experimental Evaluation of Incremental Shell Growth

在美国国家科学基金会的支持下，Waselkov博士和他的同事将研究东方牡蛎（Crassostrea virginica）的生长模式，以确定生长与水温季节性变化之间的关系。这项工作的目的是确定对牡蛎壳的分析是否可以确定牡蛎被收集的季节。初步证据表明，在温度发生显著季节性变化的温带水域，这种方法是可行的。不太清楚的是，同样的模式是否也适用于墨西哥湾等较温暖的地区。研究人员将用几种方法检查阿拉巴马州和马里兰州两个地方的牡蛎生长情况。牡蛎将被标记并在已知的条件下生长两年，然后再收获。温度将被电子记录。野生和孵化的牡蛎（已知）年龄，并将按顺序用四环素染色，以便在整个年周期中对生长模式进行时空识别。分析方法将包括传统的光学显微测量，数字图像分析与时间序列分析和使用扫描质子微探针。这项技术的成功发展将具有重要的考古意义。在史前北美的许多地区，牡蛎是一种主要的食物，在保存完好的考古遗址中广泛发现。科学家们希望了解拥有简单技术的史前人类如何在广泛的环境中生存并利用现有的自然资源。为了做到这一点，他们试图确定各个地点被占用的季节和时间长度。这是非常困难的，牡蛎壳研究将有望提供一种技术来实现这一目标。

Waselkov With National Science Foundation support Dr. Waselkov and his colleagues will study the growth patterns in Eastern oysters (Crassostrea virginica) to determine the relationship between growth and seasonal changes in water temperature. The goal of the work is to determine whether analysis of oyster shells will permit determination of the season when the oyster was collected. Preliminary evidence indicates that such an approach is possible in temperate waters where significant seasonal variation in temperature occurs. It is less clear whether the same pattern holds in warmer areas such as the Gulf of Mexico. The investigators will examine oyster growth from two locations, Alabama and Maryland, with several methods. Oysters will be marked and grown under known conditions for two years before being harvested. Temperature will be electronically logged. Both wild and hatched spawned oysters (of known) age and will be stained with tetracycline in a sequence that will allow spatio- temporal identification of growth patterns throughout the annual cycle. Analytic methods will include traditional optical micrometry, digital image analysis with time series analysis and use of a scanning proton microprobe. The successful development of this technique will have important archaeological implications. Oysters formed a major dietary item in many areas of prehistoric North America and are widely found in archaeological sites where they are well preserved. Scientists wish to understand how prehistoric peoples with simple technologies subsisted in a wide range of environments and made use of available natural resources. To do this, they attempt to determine the seasons and length of time individual sites were occupied. This can be extremely difficult to do and the proposed oyster shell study will, hopefully, provide a technique to accomplish this.