Bioarchaeological Evidence of Violence between the Middle and Late Formative (500-400 BC) in the Peruvian North-Central Coast

In this study, we address interpersonal violence during the transition between the Middle and the Late Formative periods in the Central Andes, a critical period of political disintegration, hypothesized population pressure, and reorganization of the belief systems that is poorly known from a bioarchaeological viewpoint. Our objective is to understand the nature of the violence and associated factors in this context based on a detailed description of skeletal trauma in 67 well-preserved individuals (20 adolescents and adults and 47 subadults) recovered from Quebrada Chupacigarro cemetery (500-400 BC); this site is located in the middle valley of Supe on the Peruvian north-central coast. To detect patterns and potential causes, we registered the prevalence of traumatic injury according to age, sex, anatomic location, mechanisms (blunt, sharp, mixed, etc.), timing (antemortem or perimortem), and manner (inflicted or accidental). The results show a high prevalence of fractures in the whole population, but especially in adolescents and adults. Eighty percent of the adolescents and adults perished due to the intentional trauma and show patterns that suggest repetitive episodes of interpersonal violence. Perimortem injuries in the skull, face, and thorax are compatible with lethal interpersonal violence. The findings support a probable scenario of intercommunity violence in the middle valley of Supe around 500-400 BC. Este estudio aborda la violencia durante la transicion entre el Formativo Medio y el Formativo Tardio en los Andes Centrales, periodo critico de desintegracion politica a nivel regional, de hipotetica presion poblacional y reorganizacion de los sistemas de creencias, pobremente conocidos desde el punto de vista bioarqueologico. Nuestro objetivo es entender la naturaleza de la violencia y sus factores asociados, con base en un detallado analisis de traumatismos esqueleticos en 67 individuos bien preservados (20 adolescentes y adultos y 47 subadultos) recuperados del cementerio Quebrada Chupacigarro (500-400 aC, valle medio de Supe, Costa Norcentral del Peru). La prevalencia de traumatismos fue registrada segun sexo, edad, localizacion anatomica, mecanismo (contuso, cortante, mixto, etc.), temporalidad (antemortem y perimortem) y manera (infligido o accidental), para detectar patrones y causas potenciales. Los resultados muestran una alta prevalencia de traumatismos, aproximadamente el 80% de los adolescentes y adultos (16/20) perecio como resultado de traumatismo infligido, con patrones de lesion que sugieren eventos repetitivos de violencia interpersonal. Las lesiones perimortem en los huesos del craneo, la cara y el torax son compatibles con violencia interpersonal de caracter letal y sugieren un escenario probable de violencia intercomunitaria en el valle medio de Supe alrededor del 500-400 aC.