Lad Susan E, Daegling David J, McGraw W Scott
Department of Anthropology, University of Florida, Gainesville, Florida, 32611.
Department of Anthropology, The Ohio State University, Columbus, Ohio, 43210.
Am J Phys Anthropol. 2016 Nov;161(3):426-435. doi: 10.1002/ajpa.23041. Epub 2016 Jun 27.
Independent lines of evidence suggest that osteonal bone remodeling is a function of both mechanical (i.e., changes in stress) and non-mechanical (i.e., metabolic needs related to calcium liberation) factors. The degree to which secondary bone reflects mechanical factors, however, is incompletely understood despite the common assumption that the stress environment mediates remodeling activity. Here, we investigate whether there are remodeling differences between regions of primate mandibular bone known to have distinct stress environments.
Osteon density, osteon fragment density, and relative osteonal area are measured as indicators of remodeling activity from postcanine and symphyseal thin sections of four sympatric monkey species (N = 20 total) from Taï Forest, Côte d'Ivoire: Piliocolobus badius, Colobus polykomos, Cercocebus atys, Cercopithecus diana. Subfamily and regional effects were assessed by two-way ANOVA.
Symphyseal bone has lower osteonal density, fragment density and relative osteonal area than postcanine bone in all species, indicating relatively low remodeling activity in symphyseal bone, despite the likelihood of relatively high stresses in its lingual cortex. Subfamily differences in postcanine remodeling are significant in that colobines exhibit greater remodeling than cercopithecines.
The data suggest that high strains are not requisite for bone remodeling. How the lingual symphysis negotiates a high strain environment without the reparative benefit of remodeling is yet to be elucidated, but the data prompt reevaluation of the relationship of targeted remodeling to stress histories. Differences in osteonal bone density between taxa might reflect feeding or dietary influences on remodeling activity, but sample composition prevents parsing behavioral from other taxon-specific effects.
独立的证据表明，骨单位骨重塑是机械因素（即应力变化）和非机械因素（即与钙释放相关的代谢需求）共同作用的结果。然而，尽管人们普遍认为应力环境介导重塑活动，但次生骨反映机械因素的程度仍未完全明了。在此，我们研究了在已知具有不同应力环境的灵长类下颌骨区域之间是否存在重塑差异。
测量骨单位密度、骨单位碎片密度和相对骨单位面积，作为来自科特迪瓦伊塔伊森林的四种同域猴类（共N = 20只）后犬齿和耻骨联合薄片中重塑活动的指标：红疣猴、多疣黑白疣猴、黑猩猩、戴安娜长尾猴。通过双向方差分析评估亚科和区域效应。
在所有物种中，耻骨联合骨的骨单位密度、碎片密度和相对骨单位面积均低于后犬齿骨，这表明耻骨联合骨的重塑活动相对较低，尽管其舌侧皮质可能承受相对较高的应力。后犬齿重塑的亚科差异显著，叶猴类的重塑比猕猴类更明显。
数据表明，高应变并非骨重塑的必要条件。舌侧耻骨联合如何在没有重塑修复益处的情况下应对高应变环境尚待阐明，但这些数据促使人们重新评估靶向重塑与应力历史之间的关系。不同分类群之间骨单位骨密度的差异可能反映了摄食或饮食对重塑活动的影响，但样本组成阻碍了将行为影响与其他分类群特异性影响区分开来。
