East-West cranial differentiation in pre-Columbian populations from Central and North America

División Antropología del Museo de La Plata (FCNyM, UNLP), Paseo del Bosque s/n, 1900 La Plata, Argentina.
Journal of Human Evolution (Impact Factor: 3.73). 04/2008; 54(3):296-308. DOI: 10.1016/j.jhevol.2007.08.011
Source: PubMed


In a recent study we found that crania from South Amerindian populations on each side of the Andes differ significantly in terms of craniofacial shape. Western populations formed one morphological group, distributed continuously over 14,000km from the Fuegian archipelago (southern Chile) to the Zulia region (northwestern Venezuela). Easterners formed another group, distributed from the Atlantic Coast up to the eastern foothills of the Andes. This differentiation is further supported by several genetic studies, and indirectly by ecological and archaeological studies. Some authors suggest that this dual biological pattern is consistent with differential rates of gene flow and genetic drift operating on both sides of the Cordillera due to historical reasons. Here we show that such East-West patterning is also observable in North America. We suggest that the "ecological zones model" proposed by Dixon, explaining the spread of the early Americans along a Pacific dispersal corridor, combined with the evolution of different population dynamics in both regions, is the most parsimonious mechanism to explain the observed patterns of within- and between-group craniofacial variability.

Download full-text


Available from: Rolando Gonzalez-Jose
  • Source
    • "Not only was a difference noted across environments, but also as one moved east to west. A similar east-west gradient was noted by both Pucciarelli et al. (2006, 2008), who examined variation across both North and South America, and Rothhammer & Silva (1989), who noted change moving from northwest South America towards the southeastern region. In order to assess inter-cemetery variation at Pacatnamu on the North Coast of Peru, Verano (1987) examined comparative samples from coastal and highland populations in relation to a sample from Pacatnamu and found that highland and coastal groups were distinct from one another and that geographic distance between samples correlated with biological distance. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Numerous studies have utilized craniometric data to explore the roles of genetic diversity and environment in human cranial shape variation. Peru is a particularly interesting region to examine cranial variation due to the wide variety of high and low altitude ecological zones, which in combination with rugged terrain have created isolated populations with vastly different physiological adaptations. This study examines seven samples from throughout Peru in an effort to understand the contributions of environmental adaptation and genetic relatedness to craniofacial variation at a regional scale. Morphological variation was investigated using a canonical discriminant analysis and Mahalanobis D2 analysis. Results indicate that all groups are significantly different from one another with the closest relationship between Yauyos and Jahuay, two sites that are located geographically close in central Peru but in very different ecozones. The relationship between latitude/longitude and face shape was also examined with a spatial autocorrelation analysis (Moran's I) using ArcMap and show that there is significant spatial patterning for facial measures and geographic location suggesting that there is an association between biological variation and geographic location.
    Full-text · Article · Feb 2015 · Anthropologischer Anzeiger
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The study of evolutionary relationships among human populations is fundamental to inferring processes that determine their structure and history. Among the different data types used to infer such relationships, molecular data, particularly nuclear and mitochondrial DNA, are preferred because of their high heritability and the low probability of changes during development. However, although the reliability of relatedness patterns based on other traits is discussed, except in unusual circumstances most prehistoric populations remain within the domain of morphological study. Therefore the primary goal of this study is to test the reliability of relatedness patterns constructed on the basis of craniometric data on a regional scale. In particular, we analyze samples from populations belonging to the Chaco, Pampa, and Patagonia regions of South America for which craniometric and molecular data are available. We compare a strongly supported relatedness pattern based on molecular data with the results obtained through landmark-based and semilandmark-based facial data. The matrices based on Euclidean distance for morphometric data and DA distances for molecular data were used to perform principal coordinates analyses and to obtain reticulograms. Finally, a principal components analysis of all individuals was performed with morphometric data. The results indicate that ordination analyses yield slightly different results depending on the morphometric data used. However, the reticulograms obtained with both landmark-based and semilandmark-based data allow the separation of the Chubut samples from the Chaco samples, with the Pampa sample in between the others; this pattern is congruent with molecular-based analyses. As a consequence, our results indicate that facial morphometric data allow the inference of the structure and history of the prehistoric populations for the studied region.
    Full-text · Article · Mar 2007 · Human Biology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The upper bicuspid tooth has two well defined ridges which demonstrate various morphological characteristics offering a differentiation in philogenetic typing. These ridges are known as disto-sagital crests and are also termed Uto-Aztec premolars due to the fact that such formations have been observed only in the Uto-Aztec lingual groups in the Southwestern U.S. and part of Mesoamerica. In this particular report the dental trace is specific to a right upper bicuspid pertaining to a pre-Hispanic skull exhumed from the Las Locas Cemetery located in Quibor, Lara State, Venezuela
    Full-text · Article · Jan 2008
Show more