The argument about tools indicating a change in diet: perhaps the baskets and pounders used for vegetable diets didn't survive as long as the flint spearheads.

The argument about tools indicating a change in diet: perhaps the baskets and pounders used for vegetable diets didn't survive as long as the flint spearheads. They could seem to 'disappear' in the historical record, simply because they leave no recognizable long-term evidence.