Mechanical Differences in Skeletons between Primates and Other Common Mammals

采用异速生长和主成分分析的方法，比较了包括人类在内的灵长类动物的颅后长骨与其他常见哺乳动物的长骨。骨测量数据为148种长骨，横断面几何学数据为40种长骨。当通过控制体重进行比较时，非人灵长类动物的四肢骨骼通常比普通哺乳动物的四肢骨骼更长，在骨干和关节表面的直径都更大，在骨干的中段更坚固。在主成分分析中，灵长类动物明显地从常见哺乳动物中分离出来。许多陆栖灵长类和树栖非灵长类哺乳动物位于这两个类群的边界附近。在灵长类动物的后肢中，粗壮的和几个直径特别占优势。人类属于灵长类，不同于普通的哺乳动物。针对这些差异，指出了灵长类的习性位置行为，即灵长类主要生活在树栖三维空间，普通哺乳动物主要生活在陆地二维平面上。异速生长的指数在长度上接近1/3，在截面模数上接近1.0，这表明了弯曲的粗壮。哺乳动物长骨的比例发生了异距变化，不是为了抵抗屈曲，而是为了抵抗弯曲。人类在哺乳动物，特别是灵长类动物的这些特征的基础上发育出了后肢骨骼。

Postcranial long bones of primates including humans were compared with those of other common mammals by means of the allometry and the principal component analysis. Materials were long bones of 148 species in the osteometrical data and those of 40 species in the data of the cross-sectional geometry. The limb bones of nonhuman primates were generally longer, larger in diameters both at the shaft and the articular surface, and more robust at the mid-shaft than those of common mammals when the comparisons were made by controlling body mass. Primates clearly made a group separated from the common mammals in the principal component analysis. Many terrestrial primates and arboreal non-primate mammals were situated near the border of the two groups. The robust and several diameter are particularly dominant in the hindlimbs of primates. Humans belong to the primate group and differ from the common mammal group. The habitual positional behavior was pointed out in relation to these differences, that is, the primates live dominantly in the arboreal three-dimensional space and the common mammals on the terrestrial two-dimensional plane. The exponents in allometry were nearly 1/3 in length and 1.0 in the section modulus which indicates the bending robusticity. The proportions of mammalian long bones were allometrically changed not to resist against the buckling but to resist against the bending. Humans developed the hind limb bones on the bases of these characteristics in mammals, especially in primates.