Much recent archaeological work has been aimed at attempts to reconstruct ancient subsistence and ecological patterns. Ethnographic observations by the author in eastern Peru indicate that domesticated dogs may play a significant role in distorting the archaeological record as it is reflected in unmodified mammal bone. These observations indicate that medium-sized dogs may totally devour the bone of small animals and destroy identifiable portions of the bone of medium-sized animals, leaving only the remains of large animals in condition for identification. The possibility of such destruction in the past indicates the need for caution in evaluating subsistence on the basis of bone remains in archaeological sites.