Formativo de arica

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FORMATIVE ADAPTATIONS, DIET, AND ORAL HEALTH IN THE AZAPA VALLEY OF NORTHWEST CHILE
James T. Watson, Iván Muñoz Ovalle, and Bernardo T. Arriaza

Indicators of oral health were recorded in a sample of 200 Formative period (1500 B.C.–A.D. 500) skeletons from archaeological sites located in the Lower Azapa Valley of northwest Chile.This period represents a major shift in subsistence strategies in the Atacama Desert, as coastal groups adopted agriculture and moved deeper into the valley. Frequencies of caries and antemortem tooth loss were compared between site locations (coast vs. valley) and by archaeological phase (early vs. late) to interpret the degree to which these incipient agriculturalists were reliant on domesticatedresources. Overall, frequencies of caries (11.9 percent) and tooth loss (11.6 percent) are somewhat higher than for other prehistoric groups practicing a mixed subsistence strategy. However, residents of the interior valley exhibited significantly more dental decay and tooth loss than those along the coast. Our results identify that although the Formative period residents of the Lower AzapaValley practiced a mixed subsistence strategy, the degree of reliance on agricultural production differed between the coast and the valley. We propose that these differential patterns in oral health are tied to local investment, adaptive cycles, and niche construction. Indicadores de la salud oral fueron registrados en una muestra de 200 esqueletos del periodo Formativo (1500 a.C.–500 d.C.) excavada envarios sitios arqueológicos del Valle de Azapa en el noroeste de Chile. Este periodo representa un cambio significativo en la estrategia de subsistencia dentro del Desierto de Atacama, conforme los grupos costeros adoptaron la agricultura y varios de ellos se mudaron al valle. Se compararon las frecuencias de caries y pérdida de dientes entre las localidades (costa y valle) y entre las fasesarqueológicas (temprana y tardía) para interpretar en qué grado estos grupos de agricultores incipientes dependían de recursos domesticados. En general, las frecuencias de caries (11,9 percent) y de pérdida de dientes (11,6 percent) son ligeramente más elevadas en comparación a otros grupos que practican una estrategia de subsistencia mixta. Sin embargo, los residentes del valle exhibieron máspatología oral que los que vivían en la costa. Estos resultados identifican que durante el periodo Formativo los residentes del Valle de Azapa practicaban una estrategia de subsistencia mixta pero el porcentaje de dieta agrícola era diferente entre la costa y el valle. Es muy probable que la diferencia entre los patrones de salud oral esté ligada a una inversión local, ciclos de adaptación y laconstrucción de nichos.

T

he Atacama Desert of northern Chile and southern Peru is a 966-km (600-mi) strip of land along the Pacific coast and bounded to the east by the Andes Mountains. It is the driest desert in the world (Rech et al. 2003) yet supported some of the earliest permanently settled foraging groups centuries prior to the introduction of agriculture in the region (Arriaza 1995). Theextremes of the Atacama are balanced by the immense biotic richness of the Pacific Ocean along the coast, narrow but fertile river valleys that provide direct access to diverse resources in higher elevations,

and the rich marshy deltas that connect these two biological corridors. Ancient populations living in the region had to adapt both culturally and biologically to an environment of extremes, andnowhere is this more evident than in the transition to agriculture in the Lower Azapa Valley of northwest Chile. Here we explore the cultural and biological processes involved in, and the consequences of, dietary change during the Formative transition in skeletal remains from a series of archaeological sites near Arica, Chile. The foraging-to-farming transition represents

James T. Watson...