Development of a Stable Isotope Technique for Sourcing Olivella Shell Beads in California

开发用于在加利福尼亚州采购 Olivella 贝壳珠的稳定同位素技术

• 批准号: 0504615
• 负责人: Jelmer Eerkens
• 金额: --
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0504615&HistoricalAwards=false
• 关键词: Development; Stable; Isotope; Technique; Sourcing

Shell beads comprised a type of currency for Native American Californians. In parts of the state, beads could be used to purchase goods, to buy one's way into elite social groups, or to acquire services such as labor from other individuals. Shell bead currency also facilitated prehistoric commerce. Native peoples established extensive trade networks to move obsidian, baskets, food, salt, and other goods. For unknown reasons, the shell of a certain small-bodied marine snail, Olivella biplicata - the purple olive, was chosen to serve in this capacity. Derived from the Pacific Coast, Olivella beads are found as far east as Utah, Colorado, and Idaho. A large number of these beads were made in Southern California in the Santa Barbara area where extensive bead production centers are well known. The prominence of these centers has led some archaeologists to propose that Santa Barbara "mints" were responsible for the production of most if not all beads, despite the fact that Olivella is found in abundance all along the California and Oregon coast.Jelmer Eerkens and Howard Spero will develop a method to fingerprint the source of shell beads using oxygen and carbon isotopes. Based on preliminary data from modern shells collected in Santa Barbara, Monterey Bay, Bodega Bay, and Southern Oregon, they have shown that shells growing in certain regions along the coast have distinctive isotopic signatures due to differences in seawater temperature and upwelling. With the current funding they will expand the geographic breadth of that study and include ancient shells to determine how far back in time their fingerprinting method can be extended. This basic research will ultimately allow archaeologists to address several interesting and related questions, some of which will be touched upon as part of the current research. Were, in fact, Santa Barbara inhabitants responsible for the production of all money beads found throughout the state? If so, did they maintain control over the production of such beads throughout all of prehistory, or did a "centralized mint" only appear at a certain point in time? If not, where else were shell beads produced? Finally, the research will also provide valuable paleoclimatic data on past changes in sea surface temperature and upwelling. Are conditions today similar to those in the past? If not, how have they changed through the millennia? Can we correlate other paleoenvironmental data (e.g., fishery production, vegetation, snowfall, etc) to ancient sea surface temperature and upwelling, so that we may better understand, and predict for the future, how changes in one affect the others?The investigators plan to incorporate the findings into an instructional module for school children at the Anthropology Museum at UC Davis, where over 500 K-12 school children visit each year. Children learn about pre-contact Native American lifeways and how archaeologists reconstruct the past from material remains. This module will show how technical-sounding analytical techniques (i.e., mass spectrometry) are used to answer simple-sounding questions (i.e., who traded with whom). Such outreach brings the past alive by providing interactive and hands-on experience with archaeologists and real artifacts.

贝壳珠子是美国加利福尼亚土著人的一种货币。在国家的部分地区，珠子可以用来购买商品，购买进入精英社会团体的方式，或从其他个人那里获得劳动力等服务。贝壳珠货币也促进了史前商业的发展。土著民族建立了广泛的贸易网络，以运送黑曜石、篮子、食物、盐和其他货物。不知道为什么，一种身体很小的海蜗牛的壳，Olivella biplicata -紫橄榄，被选中担任这个角色。来自太平洋海岸，Olivella珠被发现作为远东犹他州，科罗拉多，和爱达荷州。大量的这些珠子是在南加州的圣巴巴拉地区制造的，在那里广泛的珠子生产中心是众所周知的。这些中心的突出地位使一些考古学家提出，圣巴巴拉的“薄荷”负责生产大多数（如果不是所有）珠子，尽管事实上，在沿着加州和俄勒冈州海岸发现了大量的Olivella。耶尔默·埃尔肯斯和霍华德·斯佩罗将开发一种方法，利用氧和碳同位素识别贝壳珠子的来源。根据从圣巴巴拉、蒙特雷湾、博德加湾和南俄勒冈州收集的现代贝壳的初步数据，他们发现，由于海水温度和上升流的差异，生长在沿着某些地区的贝壳具有独特的同位素特征。有了目前的资金，他们将扩大研究的地理范围，包括古代贝壳，以确定他们的指纹识别方法可以延伸到多远的时间。这项基础研究最终将使考古学家能够解决几个有趣的相关问题，其中一些问题将作为当前研究的一部分。事实上，圣巴巴拉的居民负责生产全州发现的所有钱币珠子吗？如果是这样，他们是否在整个史前时期都保持着对这种珠子生产的控制，或者“中央铸币厂”只是在某个时间点出现？如果不是，还有什么地方生产贝壳珠？最后，这项研究还将提供有关过去海面温度和上升流变化的宝贵古气候数据。今天的情况与过去相似吗？如果没有，千年来它们是如何变化的？我们能否将其他古环境数据（例如，渔业生产、植被、降雪等）与古代海面温度和上升流的关系，以便我们更好地了解和预测未来，一个方面的变化如何影响其他方面？研究人员计划将这些发现纳入加州大学戴维斯分校人类学博物馆的学童教学模块，每年有500多名K-12学童参观。孩子们学习接触前的美洲原住民生活方式，以及考古学家如何从物质遗迹重建过去。本模块将展示技术性分析技术（即，质谱法）用于回答听起来简单的问题（即，谁与谁交易）。这种推广活动通过与考古学家和真实的文物进行互动和亲身体验，使过去变得生动起来。