Population Growth and Human Behavioral Change

罗伯特·凯利和他的研究小组将调查怀俄明州西北部12000年来环境变化与人口增长和人类行为下降之间的关系。由于考古学具有研究长时间跨度的能力，它在研究这两个关键变量对人类社会的影响方面处于独特的地位，就像在实验室里一样。在这样做的过程中，这项研究有助于确定环境变化，包括长期趋势和短期波动，或单独的人口密度是否足以产生人类行为的变化，或者是否最大的变化是由它们的综合影响产生的。考虑到到公元2100年世界人口将达到110亿，以及持续的环境变化，规划未来应该利用现有的最好的实验室，深刻的人类和环境历史。三名研究生将协助这项分析，并在他们的论文中使用该网站的数据。为了延续悠久的传统，凯利将在公开讲座中使用该网站的分析来讨论环境和人口对人类行为的影响。该项目利用现有数据，例如附近湖泊的花粉核和放射性碳测年的区域数据库，来重建环境和区域人口。该项目的主要贡献是分析人类行为变化的证据，这些证据是基于凯利和他的团队最近在怀俄明州大角山（bighhorn Mountains）发掘的考古遗址阿尔姆避难所（Alm Shelter）的数据。Alm Shelter提供了12000年人类使用的记录，它位于悬垂的悬崖下，干燥，因此提供了很好的有机材料保存。通常情况下，构成遗址的土层已经被破坏了，穴居动物或人类活动（如挖坑）移动了文物。把考古遗址想象成一本从下往上读的书，这样的干扰会把段落——文物和骨头——从一章移动到另一章，使这本书难以阅读。但阿尔姆谢尔特的情况并非如此；这个地方的岩层是完整的，并以缓慢的速度积累，随着时间的推移保持不变。这允许进行独特的分析。考古学家使用一种被称为“年龄深度模型”的统计方法，根据文物的深度来确定其年龄范围。考虑到这个遗址的精心挖掘，从遗址中找到的每一件文物、骨头和其他物品都可以确定一个精确的年龄范围。这允许一种新的分析方法，在这种方法中，人工制品和其他遗骸的丰度变化可以作为年龄范围的分布进行检查。然后可以对这些分布进行统计分析，以确定不同种类的人工制品（如抛射点）或不同种类的动物遗骸何时同步变化，以及这些变化与该地区过去已知的环境和人口变化之间的关系。利用人工制品和废弃的动植物遗骸作为过去人类行为的证据，这种分析提供了一种研究行为如何随着环境变化和人口密度而变化的方法。该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知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Robert Kelly and his research team will investigate the relationships between environmental change and human population growth and decline on human behavior over a 12,000-year period in northwest Wyoming. With its ability to study long spans of time, archaeology is uniquely positioned to study, as in a laboratory, the impact of these two crucial variables on human societies. In doing so, this research helps determine if environmental change, including both long-term trends and short-term fluctuations, or human population density individually are sufficient to produce change in human behavior, or if the greatest change is produced by their combined effect. Given that world population will reach 11 billion by AD 2100, and on-going environmental changes, planning for the future should make use of the best laboratory available, deep human and environmental history. Three graduate students will assist in this analysis and use the site’s data for their dissertations. Continuing a long tradition, Kelly will use the site’s analysis in public lectures to discuss the impact of environment and population on human behavior.The project employs existing data, e.g., pollen cores from nearby lakes and a regional database of radiocarbon dates, to reconstruct environment and regional human population. The project’s main contribution is analysis of evidence of human behavioral change based on data recovered from an archaeological site, Alm Shelter, recently excavated by Kelly and his team in Wyoming’s Bighorn Mountains. Alm Shelter provides a 12,000-year record of human use, and, lying beneath an overhanging cliff, is dry and thus provides excellent preservation of organic materials. Often, the layers of earth that comprise a site have been disturbed, with artifacts moved about by burrowing animals or human activities such as digging pits. Thinking of an archaeological site as a book that one reads from the bottom up, such disturbances move paragraphs – artifacts and bones – from one chapter to another, making the book difficult to read. But that is not the case at Alm Shelter; this site’s layers are intact and accumulated at a slow rate that remained constant over time. This permits a unique analysis. Archaeologists use a statistical method known as an “age-depth model” to assign an age-range to artifacts based on their depth. Given this site’s careful excavation, a tight age-range can be assigned to literally every single artifact, bone, and other item recovered from the site. This allows a new analytical approach, one where the changing abundances of artifacts and other remains can be examined as distributions of age-ranges. These distributions can then be statistically analyzed to determine when different kinds of artifacts, such as projectile points, or different kinds of animal remains are changing in sync and how those changes relate to the known environmental and human population changes of the region’s past. Using artifacts, and discarded plant and animal remains as evidence of past human behavior, this analysis provides a way to examine how behavior changed in relation to environmental changes and human population density.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.