The Anasazi (or "Ancient Ones")" are thought to have derived from the Mogollon culture. They inhabited the four corners of Southern Utah, southwestern Colorado, northwestern New Mexico, and northern Arizona from about 7000 B.C. to 1300 A.D. They left behind house remains, pottery, and tools used for hunting. The Anasazi culture was always changing, so researchers divided the occupation into six different time periods called "Peco's classification ". Each time period has a different characteristic based on settlement and artifact styles. .
The first two periods of Peco's classification marked the beginning of the Anasazi as a separate culture. The Archaic period lasted from c. 7000 to c. 100 B.C. During this period, the Anasazi were gatherers. They begin to collect a variety of plant foods, with the most popular one being maize. There wasn't much archaeological evidence left, except scattered campsites and stone tool artifacts. The time period that followed was Basketmaker II (c.100 B.C. to A.D. 600). The Anasazi were given this name due to their exquisite woven baskets and sandals. These baskets and sandals as well as bags and clothing were well preserved due to them being stored in shallow caves. It was during this time frame that squash had been added as another staple to their diet. Since their crops were so meager, hunting deer and small game had become popular. The Anasazi would store their food in deep storage pits and dwelled in alcoves or caves.
The next two time periods are the most significant to the Anasazi culture because of the changes that occurred. During the Basketmaker III (c. A.D. 600 to 750), the climate was very favorable for the Anasazi. This most likely allowed for the third staple to be added to their diet: Beans. Two more important changes that took place were grey-ware pottery appearing and the bow and arrow replacing the spear. The Anasazi also expanded their territory over canyons and mesa tops, building small homes involving semi-subterranean pit-houses.