Harper Christine M, Ruff Christopher B, Sylvester Adam D
The Johns Hopkins University School of Medicine, Center for Functional Anatomy and Evolution, Baltimore, Maryland, USA.
Cooper Medical School of Rowan University, Department of Biomedical Sciences, Camden, New Jersey, USA.
Anat Rec (Hoboken). 2022 Jan;305(1):100-122. doi: 10.1002/ar.24642. Epub 2021 Apr 27.
Among human and nonhuman apes, calcaneal morphology exhibits significant variation that has been related to locomotor behavior. Due to its role in weight-bearing, however, both body size and locomotion may impact calcaneal morphology. Determining how calcaneal morphologies vary as a function of body size is thus vital to understanding calcaneal functional adaptation. Here, we study calcaneus allometry and relative size in humans (n = 120) and nonhuman primates (n = 278), analyzing these relationships in light of known locomotor behaviors. Twelve linear measures and three articular facet surface areas were collected on calcaneus surface models. Body mass was estimated using femoral head superoinferior breadth. Relationships between calcaneal dimensions and estimated body mass were analyzed across the sample using phylogenetic least squares regression analyses (PGLS). Differences between humans and pooled nonhuman primates were tested using RMA ANCOVAs. Among (and within) genera residual differences from both PGLS regressions and isometry were analyzed using ANOVAs with post hoc multiple comparison tests. The relationships between all but two calcaneus dimensions and estimated body mass exhibit phylogenetic signal at the smallest taxonomic scale. This signal disappears when reanalyzed at the genus level. Calcaneal morphology varies relative to both body size and locomotor behavior. Humans have larger calcanei for estimated body mass relative to nonhuman primates as a potential adaptation for bipedalism. More terrestrial taxa exhibit longer calcaneal tubers for body mass, increasing the triceps surae lever arm. Among nonhuman great apes, more arboreal taxa have larger cuboid facet surface areas for body mass, increasing calcaneocuboid mobility.
在人类和非人类猿类中，跟骨形态存在显著差异，这与运动行为有关。然而，由于其在负重中的作用，体型和运动方式都可能影响跟骨形态。因此，确定跟骨形态如何随体型变化对于理解跟骨的功能适应性至关重要。在这里，我们研究了人类（n = 120）和非人类灵长类动物（n = 278）的跟骨异速生长和相对大小，并根据已知的运动行为分析了这些关系。在跟骨表面模型上收集了12项线性测量数据和3个关节面面积。使用股骨头上下径估计体重。使用系统发育广义最小二乘回归分析（PGLS）对整个样本分析跟骨尺寸与估计体重之间的关系。使用RMA协方差分析检验人类与合并的非人类灵长类动物之间的差异。使用方差分析和事后多重比较检验分析PGLS回归和等比关系中属内（以及属间）的残差差异。除了两个跟骨尺寸外，所有跟骨尺寸与估计体重之间的关系在最小分类尺度上都表现出系统发育信号。当在属水平重新分析时，这个信号消失。跟骨形态相对于体型和运动行为都有所变化。相对于非人类灵长类动物，人类的跟骨对于估计体重来说更大，这可能是对两足行走的一种适应。更多陆栖类群的跟骨结节相对于体重更长，增加了小腿三头肌的力臂。在非人类大猿中，更多树栖类群的骰骨关节面面积相对于体重更大，增加了跟骰关节的活动度。
