Herrera Brianne, Peart Daniel, Hernandez Nicole, Spradley Kate, Hubbe Mark
Department of Anthropology, The Ohio State University, Columbus, Ohio.
Department of Anthropology, Texas State University, San Marcos, Texas.
Am J Phys Anthropol. 2017 May;163(1):75-84. doi: 10.1002/ajpa.23186. Epub 2017 Feb 20.
Cranial morphology has previously been used to estimate phylogenetic relationships among populations, and has been an important tool in the reconstruction of ancient human dispersals across the planet. In the Americas, previous morphological studies support a scenario of people entering the Americas and dispersing from North America into South America through Meso America, making the Mexican territory the natural funnel through which biological diversity entered South America.
We explore the cranial morphological affinities of three late Holocene Mexican series, in relation to ancient and modern crania from North and South America, Australo-Melanesia, and East Asia. Morphological affinities were assessed through Mahalanobis Distances, and represented via Multidimensional Scaling and Ward's Linkage Cluster analysis. Minimum F values were also calculated for each series.
Our results show Mexican groups share morphological affinities with the Native American series, but do not cluster together as would be expected. The minimum F estimates show between-group variation in the Americas is higher than the Asian or Australo-Melanesian populations, and that Mexican series have high between-group variance (F = 0.124), compared to the geographically larger South America (F = 0.116) and North America (F = 0.076).
These results show that the Mexican series share morphological affinities with the East Asian series, but maintains high levels of between-group variation, similar to South America. This supports the suggestion that the high phenotypic variation seen the Americas is not a result of its size, as it can be found in more constricted areas, such as the Mexican territory.
颅骨形态学此前已被用于估计不同人群之间的系统发育关系，并且一直是重建古代人类在全球范围内迁徙的重要工具。在美洲，以往的形态学研究支持这样一种情况：人们进入美洲并从中美洲从北美洲扩散到南美洲，使得墨西哥领土成为生物多样性进入南美洲的天然通道。
我们探究了三个晚全新世墨西哥样本系列的颅骨形态学亲缘关系，这些样本与来自北美洲和南美洲、澳大利亚 - 美拉尼西亚以及东亚的古代和现代颅骨有关。通过马氏距离评估形态学亲缘关系，并通过多维尺度分析和沃德连锁聚类分析进行呈现。还计算了每个样本系列的最小F值。
我们的结果表明，墨西哥群体与美洲原住民样本系列具有形态学亲缘关系，但并未如预期那样聚类在一起。最小F估计值表明，美洲群体间的变异高于亚洲或澳大利亚 - 美拉尼西亚人群，并且与地理范围更大的南美洲（F = 0.116）和北美洲（F = 0.076）相比，墨西哥样本系列具有较高的群体间方差（F = 0.124）。
这些结果表明，墨西哥样本系列与东亚样本系列具有形态学亲缘关系，但群体间变异水平较高，与南美洲相似。这支持了以下观点：在美洲观察到的高表型变异并非其面积大小所致，因为在更狭窄的区域，如墨西哥领土，也能发现这种情况。
