The eight basic features of a civilization are large population centers, a central administrative body, complex religion, job specialization, social class structures, forms of art and architecture, organized public works, and a system of writing. All of these features are made possible by efficient agricultural systems that allow a group of people within the fledgling civilization to begin specializing their skills toward one of the basic features of a civilization.
The first civilization is widely accepted to have appeared between the Tigris and Euphrates rivers in modern Iraq around 3200 B.C. The region was called Mesopotamia. Before the rise of Mesopotamia, humans were generally hunter gatherers. However, with the onset of the Stone Age and the discovery of tools, Neolithic humans began to organize themselves into communities. These communities were supported through animal domestication and farming practices. These small farming villages that settled in fertile regions were the seeds for the civilizations to take root. For example, the ancient city of Teotihuacan was able to support its population of 100,000 people because the area around the city was so fertile. This meant that a fewer number of farmers could produce the same amount, if not more, of food, which liberated a portion of society from food production and allowed them to focus on more specialized tasks, which led to the creation of writing, art, administrative government and public works.