Recent investigations of genetic variation in living populations have suggested that the
numbers of Stone Age people rose sharply sometime between 100,000 and 50,000 years ago.
Better clues to the timing and extent of ancient population shifts may reside among the fossil
bones of tortoises, hares, and other small game that supplemented Stone Age diets.
"Many archaeologists may not have appreciated the unique potential of small-game data for
examining when and where [ancient population] increases took place," say anthropologist Mary
C. Stiner of the University of Arizona in Tucson and her coworkers.
The proportion of small game in the human diet and the number of species of these animals
captured varied little from 200,000 to 9,000 years ago, Stiner's team reports. In contrast, a dramatic
change in the type of small game eaten toward the end of that period reflected sharp
growth of the human population, the researchers find