Tardieu C, Aurengo A, Tardieu B
C.N.R.S. U.A. 1137 Laboration d'Anatomie comparée, Muséeum National d'Histoire Naturelle 55 rue de Buffon, Paris, France.
Am J Phys Anthropol. 1993 Apr;90(4):455-76. doi: 10.1002/ajpa.1330900406.
The current biomechanical interpretation of the chimpanzee's bipedal walking argues that larger lateral and vertical displacements of the body center of mass occur in the chimpanzee's "side-to-side" gait than in the human striding gait. The evolutionary hypothesis underlying this study is the following: during the evolution of human bipedalism one of the necessary changes could have been the progressive reduction of these displacements of the body center of mass. In order to quantitatively test this hypothesis, it is necessary to obtain simultaneously the trajectories of the centers of mass of the whole body and of the different body parts. To solve this problem, a new method of three-dimensional analysis of walking, associated with a volumetric modelling of the body, has been developed based on finite-element modeling. An orthogonal synchrophotographic device yielding four synchronous pictures of the walking subject allows a qualitative analysis of the photographic sequences together with the results of their quantitative analysis. This method was applied to an adult man, a 3-year-old girl and a 9-year-old male chimpanzee. Our results suggest that the trajectory of the body center of mass of the human is distinguished from that of the chimpanzee not by a lower movement amplitude but by the synchronization of the transverse and vertical displacements into two periodic curves in phase with one another. The non-human primate uses its repertoire of arboreal movements in its bipedal terrestrial gait, provisionally referred to as a "rope-walker" gait. We show that the interpretation of a "side-to-side" gait is not applicable to the chimpanzee. We argue that similarly this interpretation and the initial hypothesis presuppose a basic symmetric structure of the gait, in relation to the sagittal plane of progression, similar to the human one. This lateral symmetry of the right and left displacements of the center of gravity, in phase with the right and left single supports of walking, is probably a very derived feature of the human gait. We suggest that low lateral and vertical displacements of the body center of mass are not indicative of a progressive bipedal gait and we discuss the new evolutionary implications of our results.
目前对黑猩猩双足行走的生物力学解释认为，与人类的大步幅步态相比，黑猩猩“左右摇摆”步态中身体重心的横向和垂直位移更大。该研究背后的进化假说是：在人类双足行走的进化过程中，必要的变化之一可能是身体重心这些位移的逐渐减少。为了定量检验这一假说，有必要同时获取全身和不同身体部位的重心轨迹。为了解决这个问题，基于有限元建模开发了一种与身体体积建模相关的行走三维分析新方法。一种能产生行走对象四张同步照片的正交同步摄影装置，可对摄影序列进行定性分析以及定量分析。该方法应用于一名成年男性、一名3岁女孩和一只9岁雄性黑猩猩。我们的结果表明，人类身体重心的轨迹与黑猩猩的不同，并非在于运动幅度较小，而是在于横向和垂直位移同步为两条相互同相的周期性曲线。非人类灵长类动物在其双足陆地步态中运用其树栖运动技能，暂称为“走钢丝者”步态。我们表明，“左右摇摆”步态的解释不适用于黑猩猩。我们认为，同样地，这种解释和最初的假说预先假定了步态相对于行进矢状面的基本对称结构，类似于人类的结构。重心左右位移的这种横向对称性，与行走时左右单支撑同相，可能是人类步态非常特有的一个特征。我们认为，身体重心的低横向和垂直位移并不表明是一种渐进的双足步态，并且我们讨论了我们结果的新进化意义。
