Dissertation Research: The Functional Anatomy of Late Pleistocene and Resent Human Carpometacarpal and Metacarpophalangeal Articulations

这个项目考察了手关节的形状和方向与通常通过古代人和现代人的手传递的力的水平和方向之间的关系。要研究的骨骼样本包括尼安德特人、近东方早期现代人、旧石器时代晚期人类(距今9万至20000年)。以及最近的全新世人类。尼安德特人和早期现代人都使用类似的旧石器时代中期的石器，而晚期旧石器时代的人类与石器行业有关，这些石器行业使用较小、标准化的工具类型，这需要更大范围的功率和精密夹具来制造和使用。手腕和手指关节的三维形状和方向是用立体摄影测量法测量的。相关分析被用来确定习惯性力量水平和手部肌肉机械优势对样本间关节形状差异的相对贡献。手关节解剖学中样本间差异的存在表明了不能用力传递水平解释的操纵行为的改变频率，这将证实在晚更新世人类群体之间存在着显著的工具操纵行为差异。归根结底，群体间工具使用的差异可能有助于早期解剖学上的现代人最终获得适应性的成功。

This project examines the relationships between the shapes and orientations of hand joints and the levels and directions of forces normally transmitted through the hands of archaic and recent humans. The skeletal samples to be studied consist of Neandertals, Near Eastern early modern humans, Upper Paleolithic humans (90,000 to 20,000 years B.P.) and recent Holocene humans. Both Neandertals and early modern humans used similar Middle Paleolithic stone tools, whereas later Upper Paleolithic humans are associated with stone tool industries having higher frequencies of smaller, standardized tool types which required an increased range of both power and precision grips to manufacture and employ. The three-dimensional shape and orientation of the wrist and finger articulations are measured using stereo-photogrammetry. Correlation analysis is used to determine the relative contribution of habitual force levels and hand muscle mechanical advantages, to between-sample differences in joint shapes. The existence of between-sample differences in hand joint anatomy indicative of altered frequencies of manipulative behaviors that cannot be explained by force transmission levels would confirm that significant behavioral differences in tool manipulation existed between Late Pleistocene human groups. Ultimately, between-group differences in tool usage could have contributed to the eventual adaptive success of early anatomically modern humans.