Cancellous bone and theropod dinosaur locomotion. Part I-an examination of cancellous bone architecture in the hindlimb bones of theropods
Cancellous bone and theropod dinosaur locomotion. Part I-an examination of cancellous bone architecture in the hindlimb bones of theropods
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DOI：
10.7717/peerj.5778
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发表时间：
2018-10-31
期刊：
影响因子：
2.7
通讯作者：
Lloyd, David G.
中科院分区：
文献类型：
--
作者：
Bishop, Peter J.;Hocknull, Scott A.;Lloyd, David G.
本文是三部分系列的第一部分，研究了兽脚亚目恐龙主要后肢骨中松质骨（“海绵”）的结构，并使用松质骨结构模式来推断已灭绝的非鸟类物种的运动生物力学。众所周知，松质骨对其力学环境高度敏感，并且先前已被用于推断已灭绝的四足脊椎动物，特别是灵长类动物的运动生物力学。尽管有很大的希望，松质骨结构仍然很少用于研究许多其他灭绝的脊椎动物群体，如恐龙的运动。记录和量化整个骨骼和多个骨骼的结构模式，可以提供有关松质骨结构模式和物种间差异的大量信息。在此前提下，首次采用计算机断层扫描和图像分析技术对兽脚类恐龙后肢主要骨骼松质骨的三维结构进行了描述和分析。对许多现存和灭绝的物种进行了全面的调查，确定了几种群体之间的相似性和对比模式。例如，更向茎的非鸟类兽脚亚目（如角鼻龙和龙类）表现出的松质骨结构与人类更相似，而与鸟类更密切相关的物种（如Paravians）表现出的结构模式与现存鸟类更相似。许多观察到的模式可能与运动生物力学的特定方面有关，例如站立和步态期间髋关节或膝关节屈曲的程度。另一个重要的观察结果是鸟类股骨和胫骨骨干中大量明显倾斜的骨小梁，在大型鸟类中，骨小梁沿着骨内膜表面沿着形成螺旋形图案。这些观察结果不仅为兽脚类恐龙的解剖和行为提供了新的见解，还为通过肌肉骨骼生物力学建模对运动假说进行机械测试提供了基础。
This paper is the first of a three-part series that investigates the architecture of cancellous ('spongy') bone in the main hindlimb bones of theropod dinosaurs, and uses cancellous bone architectural patterns to infer locomotor biomechanics in extinct non-avian species. Cancellous bone is widely known to be highly sensitive to its mechanical environment, and has previously been used to infer locomotor biomechanics in extinct tetrapod vertebrates, especially primates. Despite great promise, cancellous bone architecture has remained little utilized for investigating locomotion in many other extinct vertebrate groups, such as dinosaurs. Documentation and quantification of architectural patterns across a whole bone, and across multiple bones, can provide much information on cancellous bone architectural patterns and variation across species. Additionally, this also lends itself to analysis of the musculoskeletal biomechanical factors involved in a direct, mechanistic fashion.On this premise, computed tomographic and image analysis techniques were used to describe and analyse the three-dimensional architecture of cancellous bone in the main hindlimb bones of theropod dinosaurs for the first time. A comprehensive survey across many extant and extinct species is produced, identifying several patterns of similarity and contrast between groups. For instance, more stemward non-avian theropods (e.g. ceratosaurs and tyrannosaurids) exhibit cancellous bone architectures more comparable to that present in humans, whereas species more closely related to birds (e.g. paravians) exhibit architectural patterns bearing greater similarity to those of extant birds. Many of the observed patterns may be linked to particular aspects of locomotor biomechanics, such as the degree of hip or knee flexion during stance and gait. A further important observation is the abundance of markedly oblique trabeculae in the diaphyses of the femur and tibia of birds, which in large species produces spiralling patterns along the endosteal surface. Not only do these observations provide new insight into theropod anatomy and behaviour, they also provide the foundation for mechanistic testing of locomotor hypotheses via musculoskeletal biomechanical modelling.