Based on inspection of gnawing damage done to bones of modern prey animals, sets of typical damage types or patterns are recognized for certain elements. The presence of these damage patterns suggests carnivore activity even when bones exhibit no identifiable tooth marks or other obvious sign of gnawing. Observations are made of these damage types on bones of Pleistocene and Recent North American mammals, including Bison, proboscidean, Alces, Equus, Cervus, and Rangifer. Damage to the following elements is briefly described: antlers, vertebrae, scapulae, humeri, ulnae, radii, femora, tibiae, metapodials, and innominates.