Bayle Priscilla, Braga José, Mazurier Arnaud, Macchiarelli Roberto
Centre d'Anthropobiologie et Imagerie Anatomique, FRE 2960 CNRS, Université Paul Sabatier, Toulouse, France.
Am J Phys Anthropol. 2009 Apr;138(4):493-8. doi: 10.1002/ajpa.21000.
Affinities and differences in dental maturational patterns between modern humans and Neanderthals remain a matter of discussion. In particular, deciduous teeth are rare for Late Pleistocene humans, and few entire sequences have been detailed for their developmental status. Here, we report the results from the 3D virtual reconstruction and structural analysis of the deciduous lower dentition (nine teeth in situ) of the child from La Madeleine (LM4), France, the first Upper Paleolithic specimen detailed so far by means of high-resolution microtomography (microCT). With respect to the modern dental developmental standards, age at death of this individual is now more likely estimated within the interval 3-4 years. LM4 lacks the slight discrepancy between a proportionally advanced stage of mineralization of the deciduous first molar and a relatively delayed maturational level of the incisors, which is found in Neanderthals (Bayle et al.: J Hum Evol 56 [2009] 66-75). By using a Bayesian approach, we calculated the probability that its maturational sequence is found within the extant human variation as represented by a tomographic (CT) reference sample of 45 children scored according to the same protocol (Liversidge and Molleson: Am J Phys Anthropol 123 [2004] 172-180). Results show that the specific sequence of this Magdalenian individual is found three times in the comparative sample included in this study. LM4 absolute tooth size and relative dental tissue proportions are close to the modern human figures (characterized by proportionally reduced dentine volumes) and lie systematically below the values shown by the Neanderthal child from Roc de Marsal, France (OIS 5a).
现代人类与尼安德特人牙齿成熟模式的异同仍存在争议。特别是,晚更新世人类的乳牙很罕见,很少有完整序列详细说明其发育状况。在这里,我们报告了对法国拉马德莱娜(LM4)儿童乳牙列(9颗原位牙齿)进行三维虚拟重建和结构分析的结果,这是迄今为止通过高分辨率显微断层扫描(显微CT)详细研究的首个旧石器时代晚期标本。根据现代牙齿发育标准,该个体死亡时的年龄现在更有可能估计在3至4岁之间。LM4不存在乳牙第一磨牙矿化阶段相对超前与门齿成熟水平相对滞后之间的细微差异,而这种差异在尼安德特人中存在(贝勒等人:《人类进化杂志》56 [2009] 66 - 75)。通过使用贝叶斯方法,我们计算了其成熟序列出现在现存人类变异范围内(以45名儿童按照相同方案评分的断层扫描(CT)参考样本为代表)的概率。结果表明,在本研究纳入的比较样本中,这位马格德林时期个体的特定序列出现了三次。LM4的绝对牙齿大小和相对牙组织比例接近现代人类数据(其特征是牙本质体积成比例减小),且系统地低于法国罗克德马尔萨尔的尼安德特儿童(海洋同位素阶段5a)所显示的值。