Locomotion in non-avian dinosaurs: integrating data from hindlimb kinematics, in vivo strains, and bone morphology
Locomotion in non-avian dinosaurs: integrating data from hindlimb kinematics, in vivo strains, and bone morphology
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DOI：
10.1017/s0094837300020108
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发表时间：
1998-09-01
期刊：
影响因子：
2.7
通讯作者：
Carrano, MT
中科院分区：
文献类型：
--
作者：
Carrano, MT
非鸟类恐龙运动的分析一直受到阻碍，缺乏一个适当的运动模拟现存的类群。鸟类，虽然是恐龙分支的成员，但在后肢的骨骼和肌肉组织上经历了重大的变化。这些变化导致了一个独特的肢体运动学系统（包括更水平的股骨姿势和膝盖主导的肢体运动），这排除了直接使用现存鸟类作为非鸟类恐龙运动的模型。从现存的鸟类和哺乳动物的运动数据的分析表明，一般后肢运动学，骨应变和肢体骨形态之间的因果关系，这些类群。提出了一个模型，该模型将股骨中的扭转载荷量与骨方向联系起来，使得扭转在水平股骨中最大，在垂直股骨中最小。由于扭转剪切应变的骨安全系数低于纵向轴向应变，因此扭转的增加可能会随着进化时间的推移显著影响骨形态。根据这种关系解释非鸟类恐龙和哺乳动物几乎相同的肢骨尺寸和肢元素比例，支持这两个群体相似的垂直股骨姿势和髋驱动肢运动学的预测。这些信息可以用来解释恐龙的运动进化模式。进化的四足动物与大的身体尺寸和收购的curorial或graviportal肢体形态反复发生，但没有影响恐龙运动形态的基本一致性。只有衍生的腔上龙类兽脚亚目（paravians）发展出了显著的修改，基本模式的肢体使用。兽脚亚目恐龙后肢运动学和姿态的变化显然在飞行起源前不久就开始了，但直到后来获得了衍生的飞行特征后才获得了典型的现代鸟类特征。
Analyses of non-avian dinosaur locomotion have been hampered by the lack of an appropriate locomotor analog among extant taxa. Birds, though members of the clade Dinosauria, have undergone significant modifications in hindlimb osteology and musculature. These changes have resulted in a uniquely developed system of limb kinematics (involving a more horizontal femoral posture and knee-dominated limb motion), which precludes the direct use of extant birds as models for non-avian dinosaur locomotion. Analyses of locomotor data from extant birds and mammals suggest a causal link between general hindlimb kinematics, bone strains, and limb bone morphology among these taxa. A model is proposed that relates the amount of torsional loading in femora to bone orientation, such that torsion is maximal in horizontal femora and minimal in vertical femora. Since bone safety factors are lower for torsional shear strains than for longitudinal axial strains, an increase in torsion can potentially affect bone morphology dramatically over evolutionary time. Interpreting the nearly identical limb bone dimensions and limb element proportions of non-avian dinosaurs and mammals in the light of this relationship supports the prediction of similar Vertical femoral postures and hip-driven limb kinematics in these two groups.This information can be used to interpret patterns of locomotor evolution within Dinosauria. The evolution of quadrupedalism with large body size and the acquisition of cursorial or graviportal limb morphologies occurred repeatedly but did not affect the underlying uniformity of dinosaur locomotor morphology. Only derived coelurosaurian theropods (paravians) developed significant modifications of the basic dinosaurian patterns of Limb use. Changes in theropod hindlimb kinematics and posture apparently began shortly prior to the origin of flight, but did not acquire a characteristically modern avian aspect until after the later acquisition of derived flight characteristics.