Department of Anthropology, 4064 Smith Laboratory, The Ohio State University, 174 West 18th Avenue, Columbus, OH, 43210-1106, USA.
Department of Anthropology, 4064 Smith Laboratory, The Ohio State University, 174 West 18th Avenue, Columbus, OH, 43210-1106, USA.
J Hum Evol. 2020 Apr;141:102742. doi: 10.1016/j.jhevol.2020.102742. Epub 2020 Mar 13.
Antemortem enamel chipping in living and fossil primates is often interpreted as evidence of hard-object feeding (i.e., 'durophagy'). Laboratory analyses of tooth fracture have modeled the theoretical diets and loading conditions that may produce such chips. Previous chipping studies of nonhuman primates tend to combine populations into species samples, despite the fact that species can vary significantly in diet across their ranges. Chipping is yet to be analyzed across population-specific species samples for which long-term dietary data are available. Here, we test the association between enamel chipping and diet in a community of cercopithecid primates inhabiting the Taï Forest, Ivory Coast. We examined fourth premolars and first molars (n = 867) from naturally deceased specimens of Cercocebus atys, Colobus polykomos, Piliocolobus badius,Procolobus verus, and three species of Cercopithecus. We found little support for a predictive relationship between enamel chipping and diet across the entire Taï monkey community. Cercocebus atys, a dedicated hard-object feeder, exhibited the highest frequencies of (1) chipped teeth and (2) chips of large size; however, the other monkey with a significant degree of granivory, Co. polykomos, exhibited the lowest chip frequency. In addition, primates with little evidence of mechanically challenging or hard-food diets-such as Cercopithecus spp., Pi. badius, and Pr. verus-evinced higher chipping frequencies than expected. The equivocal and stochastic nature of enamel chipping in the Taï monkeys suggests nondietary factors contribute significantly to chipping. A negative association between canopy preference and chipping suggests a role of exogenous particles in chip formation, whereby taxa foraging closer to the forest floor encounter more errant particulates during feeding than species foraging in higher strata. We conclude that current enamel chipping models may provide insight into the diets of fossil primates, but only in cases of extreme durophagy. Given the role of nondietary factors in chip formation, our ability to reliably reconstruct a range of diets from a gradient of chipping in fossil taxa is likely weak.
生前和化石灵长类动物的釉质碎片常被解释为硬食物摄入（即“嗜食硬物”）的证据。对牙齿断裂的实验室分析已经模拟了可能产生此类碎片的理论饮食和加载条件。以前对非人类灵长类动物的碎片研究倾向于将种群合并为物种样本，尽管实际上物种的饮食在其分布范围内可能有很大差异。对于具有长期饮食数据的特定种群物种样本，尚未对其进行碎片分析。在这里，我们在一个生活在象牙海岸泰森林的长尾猴科灵长类动物群落中测试了釉质碎片与饮食之间的关联。我们检查了自然死亡的长尾猴、白眉猴、白臀长尾猴、绿长尾猴和三种长尾猴的第四前磨牙和第一臼齿（n=867）。我们发现，在整个泰猴群落中，釉质碎片与饮食之间的预测关系几乎没有得到支持。专门食用硬物的长尾猴表现出（1）碎片牙齿和（2）大尺寸碎片的最高频率；然而，其他具有显著程度的食谷习性的猴子，如白眉猴，表现出最低的碎片频率。此外，那些饮食中几乎没有机械性挑战或硬食的灵长类动物，如长尾猴、白臀长尾猴和绿长尾猴，表现出比预期更高的碎片频率。在泰猴中，釉质碎片的不确定和随机性质表明非饮食因素对碎片形成有很大贡献。树冠偏好与碎片之间的负相关关系表明，外源性颗粒在碎片形成中起作用，即靠近地面觅食的类群在进食时比在较高层次觅食的物种遇到更多的异常颗粒。我们的结论是，目前的釉质碎片模型可能为化石灵长类动物的饮食提供了一些见解，但仅在极度嗜食硬物的情况下。鉴于非饮食因素在碎片形成中的作用，我们从化石类群的碎片梯度中可靠地重建一系列饮食的能力可能很弱。
