Norte Chico is unusual in that it completely lacked ceramics and apparently had almost no visual art. Nevertheless, the civilization exhibited impressive architectural feats, including large earthwork platform mounds and sunken circular plazas, and an advanced textile industry. The platform mounds, as well as large stone warehouses, provide evidence for a stratified society and a centralized authority necessary to distribute resources such as cotton. However, there is no evidence of warfare or defensive structures during this period. Originally, it was theorized that, unlike other early civilizations, Norte Chico developed by relying on maritime food sources in place of a staple cereal. This hypothesis, the Maritime Foundation of Andean Civilization, is still hotly debated; however, most researches now agree that agriculture played a central role in the civilization's development while still acknowledging a strong supplemental reliance on maritime proteins.