Hominoid Torso Anatomy and Evolution

弄清骨骼变化的时间和模式对于准确理解类人猿和人类进化至关重要。人们隐含地假设，猿类和人类有着共同的躯干形状模式，这种模式在他们共同的祖先中曾出现过一次，作为一种适应在挂在树枝下的树木中移动的适应，这与四足猴子的典型不同，长臂猿和蜘蛛猴是中间的。然而，从照片和插图上看，物种之间似乎存在着更复杂的变异模式。尽管我们对化石类人猿和人类进化的解释很关键，但灵长类物种之间躯干结构的差异从未得到系统的表征，躯干元素之间或个别骨骼与整体躯干形状之间的假设联系也从未得到统计检验。这项拟议的研究将描述猴子、猿类和人类的躯干形状，量化躯干形状与现代物种肩部、胸腔、腰部和骨盆形态之间的联系，并利用这些新数据对化石类人猿和人类祖先的功能解剖和进化做出明智的推断。该项目有四个具体目标：(1)首次利用完整身体的CT扫描数据的三维重建来表征猴子和猿的躯干形状模式；(2)量化孤立躯干骨骼(肱骨、胸带、肋骨、胸骨、椎骨和骨盆)的大小和形状，并将这些数据与完整躯干的分析结果相关联，以识别反映整体躯干结构的骨形态方面；(3)评估骨骼之间的结构协变水平；以及(4)将这些结果应用于解释新的化石猿和早期人类祖先，包括新发现的脊椎骨骨盆。一只来自匈牙利的900万年前的猿类，被认为是现代猿类人类祖先最接近的化石亲戚。拟议中的研究将在网上提供40具灵长类躯干骨骼的3D CT扫描数据，以及这些身体和更大规模的骨骼样本的标志性坐标和度量数据。它将建立一个新的三维图像分析实验室，供密苏里大学哥伦比亚分校的其他学生和教师使用。这项研究还将为研究生和本科生提供进化解剖学和3D图像分析方面的实践研究经验，这些学生的目标是参与并由一名女科学家指导的代表不足的人群。

Eludicating the timing and pattern of changes in the skeleton is critical to an accurate understanding of ape and human evolution. It is implicitly assumed that apes and humans share a pattern of torso shape that appeared once in their shared ancestry as an adaptation to moving through the trees hanging below branches that differs from what is typical for quadrupedal monkeys, and that gibbons and spider monkeys are intermediate. However, a more complex pattern of variation among species appears to exist from photographs and illustrations. Despite being critical our interpretations about fossil ape and human evolution, variation in torso structure among primate species has never been characterized systematically, nor have hypothesized associations among torso elements or between individual bones and overall torso shape ever been tested statistically. The proposed research will characterize torso form in monkeys, apes and humans, quantify associations between torso shape, and shoulder, rib cage, lumbar and pelvic morphology in modern species, and use these new data to make informed inferences about the functional anatomy and evolution of fossil apes and human ancestors. This project has four specific aims: to (1) characterize pattern of torso shape in monkeys and apes for the first time using three dimensional reconstructions of CT scan data from intact cadavers, (2) quantify size and shape of isolated torso bones (humerus, pectoral girdle, ribs, sternum, vertebrae and pelvis) and correlate these data with the results of the analysis of intact torsos to identify aspects of bone form that reflect global torso structure, (3) assess the level of structural covariation among bones, and (4) apply these results to the interpretation of new fossil apes and early human ancestors, including a newly discovered pelvis of Dryopithecus brancoi, a 9 million year old ape from Hungary that is thought to be the closest fossil relative of the modern ape-human ancestor.The proposed research will provide 3D CT scan data for 40 primate torso skeletons on the web for public access, along with landmark coordinate and metric data for these cadavers and for a larger sample of skeletons. It will establish a new laboratory for three dimensional image analysis available to other students and faculty at University of Missouri, Columbia. This research will also provide hands-on research experience in evolutionary anatomy and 3D image analysis for graduate and undergraduate students, with underrepresented populations targeted for participation and mentored by a woman scientist.