As a result of their own technological developments and their intense interaction with groups from around the territory, around 500 A.D. the horticultural-pastoralist groups that inhabited the Arid North of what is now Chile became increasingly complex economically and socially, a process that would change their way of life from horticultural-pastoralist to agricultural-pastoralist. This development would reach its height around 1000 A.D., by which time most of these groups were living in clustered villages such as Likan, on the Salado River, or the Codpa ravine settlement, and would eventually come to be known as the Arica, San Pedro or Pica‐Tarapacá cultures.
Their way of life relied heavily on water works that enabled them to irrigate their extensive farm fields, which they often constructed as terraces covering the slopes of the valley walls. Livestock raisingalso occupied much of their time, as they managed large herds of llamas and alpacas. Both farming and herding required a great deal of collective labor, which in turn led to the emergence of a more complex social structurein which the existence of local authorities became the norm.