A new study of the human skeletal material from Ur, Iraq, has drawn attention to exceptional morphologies of shape, robusticity and muscle development displayed by the bones. It is proposed that these changes result from the intensive performance of restricted activities from an early age, since it is mainly whilst the skeleton is still growing that bones can be so modelled by forces imposed upon them. Some possible activities are suggested. The presence of such tasks in a population implies a role specialisation that amounts to child labour, even slavery. These extreme changes have rarely been observed in other collections.