Oaxaca and its neighbors in Prehispanic times: Population movements from the perspective of dental morphological traits

The dynamic interaction among human groups in Prehispanic Mesoamerica led to population exchange and migrations that have just recently begun to be understood from a bioarchaeological perspective. Still, little is known about the demic biological affinities between Southern Sierra Madre populations and their coeval neighbors in Mesoamerica. The present paper focuses on biological affinities as assessed though dental morphology among three Prehispanic human collections from the present state of Oaxaca, Mexico, dated to the Classic (Monte Albán) and the Postclassic periods (Zaachila and Cerro Guacamaya). Here, we assess the extent of biological relationships within the region and with select contemporaneous groups from the altiplano (the Valley of Mexico), the Gulf of Mexico and Maya area. Population dynamics within the Oaxaca Valley show continuity between Monte Albán and Cerro Guacamaya. Zaachila, though contemporary to Cerro Guacamaya, diverges from the other Oaxaca groups. At the regional level, affinity is seen between Monte Albán and its coeval sample from the Maya and Mixe-Zoque fringe region. Sites in the altiplano and the Gulf of Mexico show relationships less stable over time. However, Cholula and Teotihuacán are more consistently separate from Oaxaca samples, perhaps indicating population interactions were fairly uncommon between these two regions, at least in the time frame analyzed in this study.