Indigenous people of the Southwest developed regional pottery traditions by 500 CE using different raw materials, forming techniques, shapes, and painted design styles. Archaeologists, who study pottery to understand the past, refer to the ancient people of the Colorado Plateau as Ancestral Pueblo, and those of the central Arizona mountains, southwestern New Mexico, and northwestern Mexico as Mogollon. The pre-Hispanic inhabitants of the Sonoran Desert are referred to as Hohokam, and those of the Colorado River Valley and adjacent uplands are called Patayan.