sub-tropical near-wetland sites. Crocodiles were the largest predators encountered by hominids and are commonly found in the lake and river basins that also preserve fossil hominids in East Africa and elsewhere [2,72,73,74,75,76,77]. They inhabit settings that afforded hominids potable water and rich food sources, in particular rootstock from marsh plants and scavengeable larger mammal carcasses [78]. Given the relatively small body sizes of fossil hominids pre-dating H. erectus (e.g., H. habilis at ,1 m tall and ,40 kg body weight; P. boisei at ,1.4 m tall, 80 kg body weight), crocodile feeding traces would likely have been inflicted by younger small- to medium-sized crocodiles, as estimated from tooth mark size for OH 8 and 35 [37]. Larger crocodiles would be capable of consuming hominids completely, leaving no trace. Crocodiles may have been common hominid predators, and as such should be considered in discussions of the ecological context of human origins. 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