Sexual dimorphism is an important component of the total variation seen in populations and plays a key role in taxonomic debates. In this study, microtomographic (microcomputed tomography) techniques were applied to a sample of hominin teeth from the Sima de los Huesos site (Spain). Dental tissue proportions of the permanent canines were assessed to characterize the pattern and degree of sexual dimorphism within this population. In addition, the possible similarities and differences with the Homo neanderthalensis remains from Krapina (Croatia) and with a recent modern human sample were evaluated. A combination of classical statistical approaches with more novel techniques allowed us not only to ratify the sex allocation of the individuals previously assigned in the literature but also to estimate the sex of the youngest individuals, which were not assessed in previous studies. Likewise, the sexes of certain extensively worn canines and isolated pieces were estimated. As a result, the sex ratio observed in our dental sample from the Sima de los Huesos population is 5:9 (Nm:Nf). In general terms, both Sima de los Huesos and Krapina dental samples have a degree of sexual dimorphism in their permanent canine tissue proportions that does not surpass that of modern humans. The marked dimorphic root volume of Sima de los Huesos mandibular canines is the exception, which surpasses the modern human mean, although it falls within the 95% confidence interval. Therefore, our results do not support that dental tissue proportions of the European Middle Pleistocene populations were more dimorphic than in modern humans. However, the differences in canine tissue proportions are great enough to allow sex estimation with a high degree of confidence.

中文翻译：

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来自西马德洛斯韦索斯（西班牙布尔戈斯）的中更新世人类恒牙的牙釉质和牙本质尺寸的性别差异。

性二态性是人群中总变异的重要组成部分，在分类学辩论中起着关键作用。在这项研究中，显微断层扫描（微计算机断层扫描）技术被应用于来自Sima de los Huesos站点（西班牙）的人牙样本。评估了永久犬的牙齿组织比例，以表征该人群中性二态性的模式和程度。此外，还评估了与克拉皮纳（克罗地亚）的尼安德特人（Homo neanderthalensis）遗骸以及最近的现代人类样本之间可能的异同。经典统计方法与更新颖的技术相结合，不仅使我们能够批准先前在文献中分配的个人的性别分配，而且能够估算最年轻的人的性别，在以前的研究中没有进行评估。同样，估计了某些磨损严重的犬和孤立的犬的性别。结果，在我们的Sima de los Huesos人群的牙齿样本中观察到的性别比为5：9（Nm：Nf）。一般而言，Sima de los Huesos和Krapina牙齿样品的永久犬牙组织比例都具有一定程度的性二态性，这一水平不超过现代人类。Sima de los Huesos下颌犬的明显双态根体积是个例外，尽管它在95％的置信区间内，却超过了现代人类的平均值。因此，我们的结果不支持欧洲中更新世种群的牙齿组织比例比现代人类更为双态。然而，