大猩猩第一跖骨骨干截面形态的性别和侧别差异

Sex-and side-related differences of diaphyseal cross-sectional morphology in the first metatarsals of gorilla

目的关注大猩猩第一跖骨结构的性别差异和侧别差异.方法选取22例大猩猩作为研究对象,重建第一跖骨三维模型,选取骨干中部截面并计算截面几何形态参数(截面面积、骨密质面积、截面惯性矩、截面形状指数、极截面惯性矩、截面抵抗矩和极截面抵抗矩),进而对比上述参数在两性和侧别间的差异.结果大猩猩第一跖骨骨干截面形态在性别间差异显著,可能与雌、雄的个体尺寸和行走方式密切相关;跖骨干截面形态在侧别间无明显差异,提示右侧脚偏好行为产生的低负荷环境对跖骨干形态影响甚微.结论骨干截面几何形态分析可为灵长类动物乃至现代人群的性别和侧别差异程度拓展新的思路.

Objective To focus the sex-and side-related differences of mid-diaphyesal cross-sectional geometric properties in first metatarsals of gorilla.Methods Twenty-two gorilla specimens were selected for this research,and three-dimensional models of the first metatarsal were reconstructed.A cross-section at the midshaft of the bone was chosen for analysis,and various geometric morphometric parameters(TA,CA,Ix,Iy,Imin,Imax,Ix/Iy,J,Zx,Zy and Zp)were calculated to assess differences between genders and sides.Results It shows that there are statistically significant differences between sexes,but no significant differences showing between right and left metatarsals.The pattern of sex-differentiated in gorilla is associated with the body size and locomotor behavior.The values of directional asymmetries indicates a lower load-environment caused by the right-foot preference,which is likely to shoe little effect on the diaphyseal cross-sectional morphology.Conclusion The geometric morphometric analysis of the bone shaft’s cross-section offers a novel approach to understanding sexual and lateral differences in primates and potentially in modern human populations.