Taphonomists would probably conclude that hominins had scavenged meat from an animal carcass they did not kill if fossil animal bones:

Taphonomists would probably conclude that hominins had scavenged meat from an animal carcass, they did not kill if fossil animal bones; did not contain stone cut marks, which are easily distinguishable from tooth marks. 
Some characteristics that have distinguished hominins from other primates, living and extinct are their erect posture, bipedal locomotion, larger brains, and behavioral characteristics such as specialized tool use, and in some cases communication through language.

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