Doctoral Dissertation Improvement: Human skeletal variation in the prehistoric New World: geographic, temporal and climatic effects

在美国国家科学基金会（National Science Foundation）的支持下，本杰明·奥尔巴赫（Benjamin Auerbach）先生正在调查新大陆史前人类在地理和时间上的体型和形状变化。该项目使用了从美洲各地大量考古遗址收集的骨骼的公制测量。这些测量将有助于展示印第安人的体型和形状是如何随着时间和环境的变化而变化的。具体而言，该研究将探讨对气候因素和生存策略（如饮食和食物获取）的适应如何影响身体变异。它还将讨论这些关系如何有助于解释人口历史（人口流动和祖先）。收集到的测量数据将用于推导形态特征（身高、体重和身体比例），采用传统的和最近开发的和改进的技术。将评估这些性状之间的共变，以调查身体各区域之间的形态异质性。例如，前臂长度相对于手臂长度的变化如何与肢体总长度相对于全身长度的变化相比较？同样，颅骨的形态变化与身体其他部位的变化相比如何？结果将对解释过去只关注身体某些区域的研究具有重要意义，并对确定不同身体区域对环境因素的协调反应量具有重要意义。将使用代表地理上有限区域若干时期的样本来评估这种随时间的比例和规模变化，并将这些变化与已知的人口和生存变化联系起来。结果将使用群体关系的知识来解释，并可能反过来帮助解决这些关联中的歧义。印第安人身体形状的变化和身体不同区域（例如，头骨和四肢）之间模式的对应关系从未在地理和时间上不同的样本中进行过评估。将这些模式与气候和营养等潜在影响联系起来，将阐明这些变量如何促进美洲和全球其他地方的生物多样性。此外，了解环境因素如何影响新大陆的体型和变异对于理解人类进化和多样化的这些模式至关重要。现代人类对美洲的殖民为研究这些问题提供了一个理想的模式；与人类进化中其他一些已知的主要迁徙事件相比，新大陆的人类在一个有限的时期内定居了各种各样的环境，并采用了大量的生存和文化习俗。这项研究的结果将导致对美洲原住民形态多样性的更全面的理解，以及这种物理形状多样性在多大程度上随着环境因素而变化。这些发现将更好地解释印第安人的起源、殖民和现存印第安人的多样性，以及现代人类的一般生物适应。将制定重建考古种群的身高和评估形态多样性的新标准，并提供给其他研究人员。此外，本研究进行的研究将有助于完成Auerbach先生的研究生培训。

Using support from the National Science Foundation, Mr. Benjamin Auerbach is investigating body size and shape variation among a geographically and temporally diverse prehistoric sample of New World humans. This project uses metric measures from archaeologically collected bones from an large number of sites throughout the Americas. These measures will help show how patterns of body size and shape have varied among Native Americans through time and in relation to their environments. Specifically, the study will address how physical variation has been affected by adaptations to climatic factors and to subsistence strategy (e.g., diet and food acquisition). It will also address how these relationships aid in interpreting population history (population movements and ancestry). The collected measures will be used to derive morphological characters (stature, body mass, and body proportions), employing conventional and recently-developed and refined techniques. Covariation among these characters will be assessed to investigate morphological heterogeneity among regions of the body. For example, how does variation in the length of the forearm, relative to the length of the arm, compare to variation in total limb length relative to total body length? Similarly, how does morphological variation in the skull compare to variation in the rest of the body? Results will have important implications for interpreting past studies that have only focused on some regions of the body, and for establishing the amount of coordinated response of different body regions to environmental factors. Samples that represent a number of time periods from geographically limited regions will be used to assess such changes in proportion and size over time, and relate these to known demographic and subsistence changes. The results will be interpreted using knowledge of group relationships and may, in turn, help resolve ambiguities in these associations. The variation of Native American body shape and the correspondence in patterns among different regions of the body (e.g., the skull and the limbs) have never been assessed among a geographically and temporally diverse sample. Correlating these patterns with potential influences such as climate and nutrition will elucidate how these variables contribute to biological diversity in the Americas and elsewhere around the globe. Moreover, understanding how environmental factors influence body shape and variation in the New World is critical for comprehending these patterns in human evolution and diversification in general. The colonization of the Americas by modern humans presents an ideal model by which to investigate many of these topics; New World humans settled varied environments and adopted a plethora of subsistence and cultural practices within a circumscribed period relative to some other known major migration events in human evolution. Results of this study will lead to a more holistic understanding of Native American morphological diversity and the extent to which this physical shape diversity has changed in response to environmental factors. Findings will better inform interpretations of Native American origins and colonization and diversity among living Native Americans, as well as general biological adaptation in modern humans. New standards for reconstructing stature and assessing morphological diversity in archaeological populations will be developed and made available to other researchers. Additionally, the research conducted in this study will assist in completing the graduate student training for Mr. Auerbach.