When the Spanish first entered Arizona in the 1500s, the Patayan people had evolved into what are known today as the Yuman-speaking Indians: the Yuman Indians, the Cocopah Indians, the Maricopa Indians, the Mojave Indians; and the three pais: the Hualapai—People of the Pine Trees, the Yavapai—People of the Sun and the Havasupai—People of the Blue Water. The prehistoric people left their homes by 1450 a.d. Prehistoric people refers to those Indian people who lived in Arizona before the time of recorded history. No one knows why they left their Arizona homes. Perhaps it was because very little rain fell for many years and they could not grow crops. Scientists who study the early people are called archaeologists. Archaeologists study the remains left behind by ancient people. Archaeologists believe that perhaps the soil was worn out from hundreds of years of farming. Sickness also may have caused problems. Some scientists think that the people built cliff dwellings and hilltop villages for protection. Newly arriving Indian groups may have caused fighting between the tribes. Most present-day Indians live very differently from the early native Indians. Some have adopted ways of life from the Spanish and people who came later. Others live like their modern non-Indian neighbors. A few, like the traditional Hopi people, struggle to maintain Hopi lands and customs. This ruins is called White House.  It is located in Canyon de Chelly  National Monument near  Chinle, Arizona. 34  Chapter 3 • The First People: Native Arizonans