[4] Paleoindian groups were efficient hunters and created and carried a variety of tools, some highly specialized, for hunting, butchering and hide processing.
These paleolithic people used habitat near water sources, including rivers, swamps and marshes, which had abundant fish, and drew birds and game animals.
At the latest by 9500 BCE, bands of hunters wandered as far south as Arizona, where they found a desert grassland and hunted mule deer, antelope and other small mammals.
Small bands of people traveled throughout the area, gathering plants such as cactus fruits, mesquite beans, acorns, and pine nuts and annually establishing camps at collection points.
Late in the Archaic Period, corn, probably introduced into the region from central Mexico, was planted near camps with permanent water access.
Distinct types of corn have been identified in the more well-watered highlands and the desert areas, which may imply local mutation or successive introduction of differing species.
From 1200 CE into the historic era a people collectively known as the La Junta Indians lived at the junction of the Conchos River and Rio Grande.
When making use of modern archaeological definitions of cultural divisions, in the Southwest or other areas, it is important to understand three specific limitations in the current conventions.
In the Southwest, mountain ranges, rivers and, most obviously, the Grand Canyon, can be significant barriers for human communities, likely reducing the frequency of contact with other groups.
Current opinion holds that the closer cultural similarity between the Mogollon and Ancestral Pueblo peoples and their greater differences from the Hohokam and Patayan is due to both the geography and the variety of climate zones in the American Southwest.