Stoning at Dmanisi

H. georgicus

Lots of cobbles have been found in a gully near Dmanisi, Georgia, the oldest known site of Homo erectus (or habilis or georgicus) in Eurasia. The cobbles could not have arrived there naturally and are not found in other areas of the site (Olduwayan style tools have been found instead). 

The researchers suspect that the abundance of cobbles in the gully was caused because it was a pass our ancient relatives used to attack carnivores, by stoning them, and rob them their prey. The unusually high frequencies of carnivore bones in the site would seem to support this kind of strategy and ratify our earliest relatives as active scavengers who could rob their prey to other predators by using the skills nature gave them: sociality, intelligence and two free hands. 

Full story at The Great Beyond (found at Archaeology in Europe).