No. 35: Sep-Oct 1984
Some 2 million years ago, man's supposed ancestors were meat-eaters. But were they noble hunters with dominion over other life forms? Probably not! The analysis of tool marks on ancient animal bones tells us that human tool marks predominate in regions of the bones where there was little meat, as if ancient humans were dismembering the animals for skins and other products. On the meat-bearing portions of the bones, the tooth marks of non-human carnivores predominate. Where the tool marks overlap the tooth marks of other carnivores, the tool marks are mostly on top of the tooth marks. The gist of the tool-mark analysis is that humans got to the animals second -- after the non-human carnivores. In other words, ancient humans were probably meat scavengers -- opportunists rather than the noble hunters often portrayed. As a matter of fact, one characteristic of a scavenger species is its ability to cover wide areas with little expenditure of energy, like the vultures. Now, human bipedalism is pitifully poor for running down game but great for searching far and wide with minimum physical effort. Tooth-wear studies of ancient human skulls indicate that humans were vegetarians first and meat-eaters second. This situation was suddenly reversed when Homo erectus came along. Then, according to toothwear patterns, there was a shift to a mainly meat diet. This was also the time when human territory expanded greatly geographically. The reason for these changes is unknown.
(Lewin, Roger; "Man the Scavenger," Science, 224:861, 1984.)