RESUMO
OBJECTIVES: The role of migration in the cultural development of central Mexico has long been debated. Archaeological models suggest that central Mexico likely experienced increased migration during the Epiclassic period (600-900 CE) and that migrants may have originated in northwestern Mexico. While previous biodistance analyses of Classic and Postclassic populations have come to similar conclusions, none have incorporated Epiclassic skeletal populations. This study uses multi-scalar biodistance analyses to directly evaluate archaeological Epiclassic migration models within central Mexico. MATERIALS AND METHODS: This study uses finite mixture and relationship (R) matrix analyses of cervicometric tooth dimensions to reconstruct patterns of biological affinity among Classic and Epiclassic Mesoamerican populations (n = 333), including at the central Mexican Epiclassic shrine site of Non-Grid 4 where the remains of at least 180 individuals were interred. RESULTS: Estimated inter-site phenotypic distances demonstrate support for some degree of both biological continuity and extra-local gene flow within central Mexican populations during the Classic-Epiclassic transition. Furthermore, estimated phenotypic distances and finite mixture posterior probabilities indicate central Mexican Epiclassic populations were biologically diverse, originating from various source populations throughout Mesoamerica, including the Bajío region, the Malpaso Valley, and the Oaxaca Valley. DISCUSSION: Results suggest that emphasizing both local and extra-local gene flow rather than population replacement may be more appropriate to understand central Mexican population structure during the Classic-Epiclassic transition. Moreover, analyses support previous archaeological migration models positing that Epiclassic migrants into central Mexico originated in northwestern Mexico, but also find evidence of Epiclassic migrants originating from previously unanticipated locales like southern Mexico.
Assuntos
Dente , Migrantes , Humanos , México/epidemiologia , Dinâmica Populacional , Meio AmbienteRESUMO
OBJECTIVES: We study the genetic diversity between Classic Teotihuacan and its neighboring towns trying to understand how far or close they are at the genetic level. MATERIALS AND METHODS: We use cranial nonmetric traits to study a sample of 280 adult skulls from archaeological sites running from the late Preclassic to the early Postclassic. Samples of Classic Teotihuacan were studied for La Ventilla and San Sebastián Xolalpan neighbors. For the Epiclassic period, samples from Xaltocan, Toluca valley, Mogotes and Xico were used. For the Preclassic and Postclassic samples from Xico were also used. We used a parametric bootstrap for the mean measure of divergence for the statistical analysis. RESULTS: Samples from Xico have small biodistance from Preclassic to Postclassic. Samples from Los Mogotes differ depending on the functional context of deposition, with individuals from household burials (funerary) differing from non-funerary, ceremonial interments and exhibiting affinities to Epiclassic samples from Toluca valley. Epiclassic populations from Xaltocan vary significantly from any samples analyzed. Samples from Classic period Teotihuacan vary considerably among them but form a separate genetic group from all the other populations under study. CONCLUSIONS: The great biodistance separation among Classic Teotihuacan and its neighbor villages of central Mexico let us conclude that, contrary from the classical idea that those villages were confirmed by the inhabitants of Teotihuacan's collapse: They indeed remain as separate populations by themselves.