Percher Alice M, Romero Alejandro, Galbany Jordi, Nsi Akoue Gontran, Pérez-Pérez Alejandro, Charpentier Marie J E
Institut des Sciences de l'Évolution de Montpellier (ISE-M) UMR5554, Univ. Montpellier, CNRS, IRD, EPHE, Montpellier, France.
Departamento de Biotecnología, Universidad de Alicante, Alicante, Spain.
PLoS One. 2017 Oct 26;12(10):e0186870. doi: 10.1371/journal.pone.0186870. eCollection 2017.
Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. The buccal surface of the teeth does not undergo attrition, indicating that dental microwear may directly inform about food properties. Only a few studies have, however, investigated the environmental and individual factors involved in the formation of such microwear in wild animals. Here, we examine variation of buccal microwear patterns of mandibular molars in a large free-ranging population of mandrills (Mandrillus sphinx). We first explore the influence of seasonality and individual's sex, age and tooth macrowear-expressed as the percent of dentine exposure (PDE)-on six microwear variables. Second, we analyze the interplay between individual's diet and PDE. In a last analysis, we revisit our results on mandrills in the light of other primate's microwear studies. We show that the average buccal scratch length and the frequency of vertical buccal scratches are both higher during the long dry season compared to the long rainy season, while we observe the inverse relationship for disto-mesial scratches. In addition, females present more disto-mesial scratches than males and older individuals present higher scratch density, a greater proportion of horizontal scratches but a lower proportion of vertical scratches than young animals. PDE yields similar results than individual's age confirming earlier results in this population on the relationship between age and tooth macrowear. Because seasonality and individual characteristics are both known to impact mandrills' diet in the study population, our results suggest that buccal microwear patterns may inform about individual feeding strategies. Furthermore, PDE increases with the consumption of potentially abrasive monocotyledonous plants, independently of the individuals' age, although it is not affected by food mechanical properties. Finally, buccal scratch densities by orientation appear as relevant proxies for discriminating between different primate taxa.
牙齿微观和宏观磨损分析为饮食适应性提供了有价值的信息。牙齿的颊面不会发生磨损，这表明牙齿微观磨损可能直接反映食物特性。然而，只有少数研究调查了野生动物中这种微观磨损形成所涉及的环境和个体因素。在这里，我们研究了一大群自由放养的山魈（Mandrillus sphinx）下颌磨牙颊面微观磨损模式的变化。我们首先探讨季节性以及个体的性别、年龄和牙齿宏观磨损（以牙本质暴露百分比，即PDE表示）对六个微观磨损变量的影响。其次，我们分析个体饮食与PDE之间的相互作用。在最后一项分析中，我们根据其他灵长类动物的微观磨损研究重新审视我们对山魈的研究结果。我们发现，与长雨季相比，在长旱季期间，平均颊面划痕长度和垂直颊面划痕频率都更高，而我们观察到远中 - 近中划痕呈现相反的关系。此外，雌性的远中 - 近中划痕比雄性更多，年龄较大的个体划痕密度更高，水平划痕比例更大，但垂直划痕比例比年轻个体更低。PDE得出的结果与个体年龄相似，证实了该种群中关于年龄与牙齿宏观磨损关系的早期研究结果。由于已知季节性和个体特征都会影响研究种群中山魈的饮食，我们的结果表明颊面微观磨损模式可能反映个体的进食策略。此外，PDE随着潜在磨蚀性单子叶植物的摄入量增加而增加，与个体年龄无关，尽管它不受食物机械性能的影响。最后，按方向划分的颊面划痕密度似乎是区分不同灵长类分类群的相关指标。
