They were born after an evolution of centuries. They reached their peak and declined. Some of them declined abruptly. Its rulers proclaimed themselves intermediaries with the Gods or directly as sons of God. These Gods were represented as mythological beings, a mixture of man and animal or of different animals. They usually made human sacrifices to these Gods. Society was divided into very marked social classes. The subjugated people were enslaved and provided large contingents of labor for the cultivation and construction of cities, buildings, and pyramids. The conquered peoples were forced to give tributes in minerals or agricultural products. They based their subsistence on agriculture. In the coastal empires, fishing was an essential part of their diet. They built large and complex irrigation systems. Common images in art: fish, toads, snakes, felines, eagles, condors and trophy heads of their defeated enemies. Similar techniques in ceramics, metallurgy, weaving and feather art. Permanent exchange between regions, for the variety of ecological floors.