Problem 1: Food shortages in the foothills.

hen problems arose. Some historians believe that by 5000 B.C.E., farmers in the Zagros foothills did not have enough land to grow food for the increasing population. As a result, villages began to suffer from food shortages. Below the foothills and to the south, the Euphrates and Tigris rivers ran through flat plains.

Explanation:

answer; the population in brazil is very diverse there are many races and ethnic groups