Answer:
There is instability in the production of food due to changes in the climatic condition (sun, slow, too mich heat, drought, water) which the Cahokia have no control over.
Step-by-step explanation:
It is important to state that, If I were to be in this situation I would definitely leave if my source of food was ruined. Food is found by what is planted. There are four seasonal changes "snow, too much heat, drought, and no sun" that I have no control over, and can ruin my food intake and when there is no enough water from our Mother Nature played a role in the prevention of Cahokian food. This is why they all moved back to where they originated from.