An investigation of tetrapod skull architecture using advanced computer modelling techniques.

动物的头骨必须在力量和稳定性与灵活性的矛盾要求之间取得平衡，这样它们才能尽可能大地张开嘴巴，施加最大的咬合力，而不会损害封闭的大脑和感官。爬行动物、鸟类和哺乳动物的祖先有一个坚固的头骨，除了眼睛和耳朵的开口，但他们很快就开始在眼睛后面的头骨侧面形成开口(Fenestrae)；现在不同的头骨有不同的fenestrae图案，但原因仍然不清楚。此外，头骨的整体几何形状也不同。头骨深度、大脑和/或感觉器官的大小、颌部肌肉的复杂性和颈部的长度都有差异。所有这些特征，单独或结合在一起，对头骨功能(生物力学)有重大影响，并可能导致现存动物头骨结构的根本差异。本研究的目的是了解生物力学与活体动物头骨形状之间的关系，特别是确定开窗术的生物力学意义。要做这项工作，我们需要结合机械工程师、数字成像师、骨生物学家和形态学家的专业知识，并使用先进的计算机建模技术来执行复杂的生物力学分析。在这个项目中，来自博物馆活体动物群体标本的信息(通过先进的计算机成像-高分辨率计算机X射线断层扫描获得)将被结合起来，以开发一系列头骨的准确模型。可以对这些参数进行修改以改变基本参数(例如眼睛大小、脑大小、开窗模式)，然后以模拟颌部和颈部肌肉复杂性变化、大脑和感觉器官大小变化和/或增加咬合力的方式加载。因此，我们可以第一次测试一系列解释头骨形状的理论。这项研究不仅将增进我们对一组关键生物体的发育的了解，还将加深我们对生物力学、软组织结构和骨骼形状之间复杂关系的理解。了解这种复杂的关系不仅对普通生物学，而且对医学(例如，骨骼修复和重塑、过度使用损伤、骨质疏松症)都很重要。

The skulls of animals must balance the conflicting demands of strength and stability with flexibility, so that they can open their mouths as wide as possible and apply a maximum bite force without damaging the enclosed brain and sense organs. Ancestors of reptiles, birds and mammals had a solid skull except for eye and ear openings, but they soon began to develop openings (fenestrae) in the side of the skull behind the eyes; now different skulls have different patterns of fenestrae, but it is still not understood why. Furthermore the overall geometries of skulls are different. There is variation in skull depth, in the size of the brain and/or sense organs, in the complexity of the jaw muscles, and in the length of the neck. All of these features, individually or in combination, have a major effect on skull function (biomechanics) and may underlie the radical differences in skull architecture of living animals. The aim of this research is to understand the relationship between biomechanical forces and skull shape in living animals, and in particular to determine the biomechanical significance of skull fenestrations. To do this work, we need to combine the expertise of mechanical engineers, digital imagers, bone biologists, and morphologists, and use advanced computer modelling techniques to perform sophisticated biomechanical analyses. In this project, information from museum specimens of living animal groups (obtained by advanced computer imaging - High Resolution Computed X-ray Tomography) will be combined to develop accurate models of a range of skulls. These can be modified to change basic parameters (e.g. eye size, brain size, patterns of fenestration), and then loaded in ways that simulate changing complexities of the jaw and neck muscles, changes in size of the brain and sense organs, and/or increasing bite force. As a result, we can, for the first time, test a series of theories to explain skull shape. Not only will the study advance our knowledge of the development of a key group of organisms but it will also deepen our understanding of the complex relationship between biomechanical forces, soft tissue structures and skeletal shape. Understanding this complex relationship is important, not only to general biology but also to medicine (e.g. bone repair and remodelling, over-use injuries, osteoporosis).