Age-correlated Differential Destruction of Bones and its Effect on Archaeological Mortality Profiles of Domestic Sheep and Goats

Abstract

Economic models based on growth curves predict that the optimum age to slaughter sheep and goats for meat is about 9 months, and if milk production is emphasized about 2–6 months. Mortality profiles from modern and historic flocks fit the prediction, for deaths of 2–12-month-old lambs and kids always exceed 50% of the total and commonly exceed 75%. For mortality profiles of mandibles from archaeological sites, on the contrary, ovicaprids 2–12 months old rarely exceed 50% of the total and in the majority of cases are less than 25%. Ethnoarchaeological and experimental studies show that when subjected to ravaging by domestic dogs the mandibles of adult sheep and goats survive at rates much higher than the less dense and smaller mandibles of young animals. If the actualistic age-correlated survival rates are applied to ovicaprid mandibles from archaeological sites, nearly all convert to mortality profiles that are closely similar to modern and historically documented situations.