Identification and examination of inconspicuous carnivore modifications

Bone modifications are associated with a broad range of agents, including carnivores, stone tools, sediments, etc., and can be categorized as one of two types: conspicuous or inconspicuous. Contrary to the larger, more easily identifiable conspicuous modifications, inconspicuous modifications are small, shallow and almost unnoticeable without the aid of a hand lens and strong light, making them harder and more time consuming to identify. This has led to arguments for their omission from tooth mark counts, even though their presence on the bones of archaeological and paleontological faunal assemblages have been recognized and mentioned in literature as having interpretive potential. This study employs visible light microscopy and high resolution scanning electron microscopy to present evidence that positively identifies inconspicuous carnivore modifications as abrasions that also have diagnostic morphology which differentiates them from abrasion created by other taphonomic agents. These inconspicuous carnivore marks may also be associated with the presence of soft tissue and so may help reconstruct the amount of flesh present at specific stages of carcass consumption. This study shows the interpretive potential of ICA may be substantial, requiring their inclusion in tooth mark counts for more accurate reconstructions of past carnivore behavior. Furthermore, understanding the etiology and implications of inconspicuous carnivore marks may provide a new way to interpret faunal assemblages that exhibit such marks, such as those associated with FLK Zinjanthropus, Tanzania. Such interpretations may be able to help develop stronger inferences regarding methods of hominin carcass acquisition.