An interesting, if very controversial view on the origin of agriculture:
"Climatic change at the end of the last glacial period led to an increase in the size and concentration of patches of wild cereals in certain areas (Wright 1977). The large quantities of cereals newly available provided an incentive to try to make a meal of them. People who succeeded in eating sizeable amounts of cereal seeds discovered the rewarding properties of the exorphins contained in them. Processing methods such as grinding and cooking were developed to make cereals more edible. The more palatable they could be made, the more they were consumed, and the more important the exorphin reward became for more people.
At first, patches of wild cereals were protected and harvested. Later, land was cleared and seeds were planted and tended, to increase quantity and reliability of supply. Exorphins attracted people to settle around cereal patches, abandoning their nomadic lifestyle, and allowed them to display tolerance instead of aggression as population densities rose in these new conditions.
Though it was, we suggest, the presence of exorphins that caused cereals (and not an alternative already prevalent in the diet) to be the major early cultigens, this does not mean that cereals are 'just drugs'. They have been staples for thousands of years, and clearly have nutritional value. However, treating cereals as 'just food' leads to difficulties in explaining why anyone bothered to cultivate them. The fact that overall health declined when they were incorporated into the diet suggests that their rapid, almost total replacement of other foods was due more to chemical reward than to nutritional reasons."
A while ago I touched on exorphins as well.
But what if the fix from exophins helped us develop abstract thinking and mathematics? Did the !Kung know mathematics?