Doctoral Dissertation Research: Enamel Defects, Well-Being and Mortality in a Medieval Danish Village

重建过去人群的人口统计学和健康状况一直是体质人类学的主要努力之一，不仅要了解特定人群如何生活和发展，而且要更好地了解人类与环境之间的一般生物相互作用。 牙釉质内的发育缺陷称为加重纹（AS），在生理压力期间形成，已在以前的骨骼研究中用作过去人口营养和疾病经历的衡量标准，因为对活人的研究表明牙齿缺陷与营养压力和疾病有关。 然而，骨骼样本中AS数量较高表明人群营养不良和疾病负荷较高的假设受到两个因素的混淆。 首先，目前尚不清楚个体牙列中存在AS是否一定意味着该个体比其他个体具有更高的死亡风险，因为该个体必须在压力事件中幸存下来才能获得缺陷。 其次，即使AS与较高的死亡风险相关，但个体营养和疾病水平在人群中的差异将导致骨骼样本高度选择“最弱”的个体，从而提高了曾经生活过的人群中营养压力和疾病的明显水平。 这项研究使用生存分析方法来测试AS和死亡年龄之间的关系，从一个中世纪的丹麦村庄的骨骼，以确定是否有较高的死亡风险（那些在年轻时死亡）的人有较高的发病率AS。 使用生存分析校正了从具有异质健康水平的人群中产生的选择性骨骼样本。 该项目可能表明，AS与健康的关系比以前认为的要复杂得多，但也更具信息性，并将有助于继续用于古人口研究的方法，以了解骨骼病理学与健康之间的关系，以及健康与前工业化人口过程之间的关系。

The reconstruction of the demography and health of past populations has been one of the major endeavors in physical anthropology, not only to understand how specific populations lived and developed, but to better understand the general biological interactions between humans and their environments. Developmental defects within tooth enamel called accentuated striae (AS), which form during periods of physiological stress, have been used in previous studies of skeletons as a measure of the past population's nutrition and disease experience, since studies of living people have shown that tooth defects are associated with periods of nutritional stress and disease. However, the assumption that a higher number of AS in a skeletal sample indicates a population with poorer nutrition and a higher disease load is confounded by two factors. First, it is not clear that the presence of AS in an individual's dentition necessarily means that the individual had a higher risk of death than other individuals, since the individual would have to have survived a stress event in order to acquire the defect. Second, even if AS are associated with a higher risk of death, the fact that individual levels of nutrition and disease vary within a population will result in a skeletal sample that is highly selected for the "weakest" individuals, thus elevating the apparent levels of nutritional stress and disease in the once-living population. This study uses survival analysis methods to test for a relationship between AS and age at death in skeletons from a medieval Danish village to determine whether those individuals with a higher risk of death (those dying at younger ages) had a higher incidence of AS. Using survival analysis corrects for the selective skeletal sample that results from a population with heterogeneous levels of health. The project may show that the relationship of AS to health is much more complex, but also more informative, than previously thought, and will contribute to a method that continues to be used in paleodemographic research to understand the relationship between skeletal pathology and health and between health and preindustrial population processes.