Masticatory Biomechanics and the Primate Face

这里提出的研究需要对灵长类咀嚼生物力学进行全面分析的初始阶段。主要目标是(1)确定面部骨骼应变模式如何受到主要生物力学变量(骨骼几何形状、材料特性和外力)的影响，以及(2)测试旨在解释在现存灵长类动物中观察到的面部应变模式的相似性和差异性的假设。将收集几种类型的基本数据，这些数据是全面了解灵长类摄食机制的基础。这些数据包括(1)体内和体外的骨应变，(2)咀嚼肌的肌电图、生理横截面积和肌纤维方向，(3)颅面几何的三维信息，(4)颅面骨和缝合线的材料特性。功能假说将通过使用有限元分析整合这些数据来测试，有限元分析是一种广泛使用的工程技术，旨在研究复杂几何形状的物体在载荷下如何变形。这项研究的初始阶段包括两个部分。第一个组成部分将需要修改猕猴头面部骨骼的有限元模型，以纳入新的数据(肌肉和骨骼特性、肌电以及体外和体内骨应变)，以开发一种研究灵长类颅面结构和功能的模型方法。这一阶段将使研究人员能够证明所提出的方法的可行性，它们整合大量不同类型数据的能力，以及各种类型数据对于理解与头面部器官功能形态相关的适应的重要性。第二部分将通过对Eulemur fulvus和Cebus capucinus的初步研究，初步分析类人猿和链鼻鱼在结构和功能上的差异的意义。在分析了这一初步项目的结果后，研究人员将申请资金，以扩大研究的样本规模和/或分类范围。这项研究将产生广泛的社会影响。它将：(A)提供迄今最广泛的面部生物力学检查；此类基础科学研究将在与颅面发育、生长、病理和创伤相关的临床科学中得到应用，(B)使用有限元模型，限制对未来需要使用活体动物的实验研究的需求，或至少增加其分析能力，(C)展示体质人类学固有的跨学科性质，(D)提供一个例子，说明如何结合经验数据和计算建模来分析复杂的系统，(E)加强五所大学人类学家之间的合作，以及(F)向三所大学的研究生提供资金。

The research proposed here entails the initial phase of a comprehensive analysis of primate masticatory biomechanics. The primary goals are (1) to determine how patterns of facial bone strain are influenced by major biomechanical variables (skeletal geometry, material properties, and external forces), and (2) to test hypotheses purporting to explain the pattern of similarities and differences in facial strain observed among living primates. Several types of primary data will be collected that are fundamental to a complete understanding of primate feeding mechanics. These data include (1) in vivo and in vitro bone strain, (2) electromyography, physiological cross-sectional area and muscle fiber orientation of the muscles of mastication, (3) three-dimensional information about craniofacial geometry, and (4) material properties of craniofacial bones and sutures. Functional hypotheses will be tested by integrating these data using finite element analysis, a widely used engineering technique designed to examine how objects of complex geometry deform under load. The initial phase of this research has two components. The first component will entail the modification of a finite element model of the craniofacial skeleton of Macaca to incorporate new data (muscle and bone properties, EMG, and in vitro and in vivo bone strain) to develop a model approach to the study of primate craniofacial structure and function. This phase will enable the researchers to demonstrate the viability of the proposed methods, their ability to integrate vast amounts of diverse types of data, and the significance of the various types of data for understanding adaptions related to the functional morphology of the craniofacial apparatus. The second component will include preliminary analysis of the significance of structural and functional differences between anthropoids and strepsirrhines through initial studies of Eulemur fulvus and Cebus capucinus. Following analysis of the results of this initial project, the investigators will apply for funds to expand the sample sizes and/or the taxonomic scope of the study, as indicated by our findings.This research will have a broad social impact. It will: (a) provide the broadest examination yet of facial biomechanics; such basic science research will find applications in clinical sciences related to the craniofacial development, growth, pathology, and trauma, (b) using FE models, limit the need for, or at least increase the analytical power of, future experimental studies requiring the use of live animals, (c) demonstrate the inherent interdisciplinarity of physical anthropology, (d) provide an example of how complex systems can be analyzed using a combination of empirical data and computational modeling, (e) strengthen collaborations between anthropologists in five universities, and (f) provide funding to graduate students at three universities.