Dissertation Improvement Grant: A Comparative Study of the Hand and Wrist in Cebus apella and Saimiri sciureus

论文改进补助金：Cebus apella 和 Saimiri sciureus 手部和腕部的比较研究

• 批准号: 0332961
• 负责人: Mary Marzke
• 金额: $ 0.28万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-12-15 至 2005-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0332961&HistoricalAwards=false
• 关键词: Dissertation; Improvement; Grant; Comparative; Study

Identifying skeletal features in the hands and wrists of early fossil hominid species (humans and their closest bipedal relatives) that may predict stone tool-making capabilities is of interest to anthropologists, because stone tools are found in fossil deposits where more than one hominid species has been recovered. Chimpanzees have traditionally been used as a model for early hominid hands because of their close genetic relationship to humans and their use of tools in the wild. Capuchin monkeys, less closely related to humans, rival chimpanzees in their tool-using abilities in captivity. Capuchins are unique among monkeys in that they frequently pound objects against trees in the wild. Pounding may be pre-adaptive for tool-making behaviors; therefore, capuchins may provide an alternative nonhuman primate model for identifying features in the fossil hands of early hominids that reflect stresses on the hand associated with pounding and forceful manipulation of stones.The question addressed by this study is whether there are features of capuchin hand muscles and bones that reflect their distinctive manipulative behaviors. The answer will be approached as follows. First, relative cross-sectional areas of cadaver hand muscles will be compared in Cebus apella (tufted capuchin) and Saimiri sciureus (common squirrel monkey, a close relative of capuchins). Cross-sectional area reflects a muscle's potential to exert force and is estimated by measuring its volume and its fiber length. Second, relative leverage of these same muscles (i.e., their lever arms) will be estimated by passively moving each hand joint while simultaneously measuring (1) the joint's full range of motion and (2) the distance moved by the muscle tendon crossing the joint. These measurements will allow estimation of each muscle's potential to exert torque, i.e. the relative ability of each muscle to rotate a bone at a joint. Finally, skeletal features that reflect relative areas and lever arms of these muscles will be identified, described and measured, where possible. It is predicted that capuchins will have some hand muscles that are capable of generating relatively greater torques than in squirrel monkeys, and that these muscles will be associated with distinct skeletal features. These data are essential to analysis of manipulative capabilities. They have not been previously obtained for either species. Once muscles with large torque potentials have been identified in the capuchins, these muscles can be tested in a future study using electromyography, to determine whether they are indeed strongly recruited during pounding behaviors. Training in the techniques and interdisciplinary approach used in this study will be offered to other researchers at workshops, to undergraduate and graduate students at Arizona State University, and to high school students, including underrepresented groups, at open houses sponsored by the IGERT Neural & Musculoskeletal Adaptations in Form & Function program (NSF#9987619) at Arizona State University, to which both the PI and Co-PI are attached. Broad dissemination of the collected data, techniques, and interdisciplinary approach will allow for research collaborations worldwide to use the capuchin as an alternative nonhuman primate model in clinical research on hand function.

人类学家感兴趣的是，识别早期化石原始人物种(人类及其最近的两足亲属)手和手腕上的骨骼特征，以预测石器制造能力，因为在化石沉积物中发现了石器，在那里发现了不止一个原始人物种。黑猩猩传统上被用作早期人类双手的模型，因为它们与人类有着密切的遗传关系，而且它们在野外使用工具。卷尾猴与人类的亲缘关系不那么密切，在圈养条件下，它们的工具使用能力与黑猩猩不相上下。卷尾猴在猴子中是独一无二的，因为它们经常在野外用物体撞击树木。撞击对于制造工具的行为可能是预适应的；因此，卷尾猴可能提供了一种替代的非人类灵长类动物模型，用于识别早期原始人化石手中反映与敲打和强力操纵石头相关的手部压力的特征。本研究解决的问题是，卷尾猴手部肌肉和骨骼是否有反映其独特操纵行为的特征。答案将如下所示。首先，我们将比较卷尾猴(Cebus Apella)和卷尾猴(Saimiri Scureus)(卷尾猴的近亲，普通松鼠猴)身体手肌肉的相对横截面积。横截面积反映了肌肉施加力量的潜力，并通过测量其体积和纤维长度来估计。其次，这些肌肉(即它们的杠杆臂)的相对杠杆率将通过被动移动每个手关节来估计，同时测量(1)关节的全部运动范围和(2)肌腱穿过关节移动的距离。这些测量将允许估计每块肌肉施加扭矩的潜力，即每块肌肉在关节处旋转骨骼的相对能力。最后，在可能的情况下，将识别、描述和测量反映这些肌肉的相对区域和杠杆臂的骨骼特征。据预测，卷尾猴的一些手部肌肉能够产生比松鼠猴子相对更大的扭矩，这些肌肉将与不同的骨骼特征相关联。这些数据对于分析操纵能力是必不可少的。这两个物种以前都没有获得过它们。一旦在卷尾猴身上发现了具有大扭矩潜力的肌肉，就可以在未来的研究中使用肌电图仪测试这些肌肉，以确定它们是否确实在撞击行为中被强烈招募。这项研究中使用的技术和跨学科方法的培训将在研讨会上提供给其他研究人员，亚利桑那州立大学的本科生和研究生，以及高中生，包括代表不足的群体，在亚利桑那州立大学由IGERT神经和肌肉骨骼适应形式和功能项目(NSF#9987619)赞助的开放日上，PI和Co-PI都附在该项目上。收集的数据、技术和跨学科方法的广泛传播将使世界各地的研究合作能够在手功能的临床研究中使用卷尾猴作为替代的非人类灵长类动物模型。