The Eastern Foothills

The third major environment encompassed by Tahuantinsuyu is the region where the high Andes decrease in altitude toward the east. In modern Peru and Ecuador, the Andes drop into the Amazonian lowlands to become a vast tropical rainforest. Here the foothills are called the ceja de la montana, or ceja for short. In Bolivia and Argentina, the Andes descend into flat, low-lying areas called the Llanos de Mojos and Gran Chaco, which are dry in the winter and flooded in the summer. Finally, in Argentina, the Andes drop into large grasslands called pampas which are similar to the Great Plains of the United States.

The Incas were a highland people, fully adapted to the climate and products of the highland zones. When they attempted to extend their

Empire into the eastern lowland regions, they had much less success, particularly when they invaded the tropical rainforests of Amazonia. The heat, humidity, dense vegetation, and guerrilla tactics of the groups living there made Inca warfare ineffective. Therefore, Tahuantinsuyu extended very little into this zone.

Nevertheless the ceja region of eastern Peru had economic importance to the Incas. In this environment of high rainfall and temperatures, certain tropical plants and animals are found—such as the coca plant—that were prized by the Incas. Coca was widely used by Andean people for chewing (much like tobacco), and it had great ceremonial significance to the Incas. Chewing coca reduces feelings of cold, fatigue, and thirst; thus it was helpful to farmers toiling in their fields in the highlands. Coca is still widely used for these purposes today (Hanna 1976).

Other products from the eastern foothills that were of value to highland people included colorful feathers from the birds that lived there, which were used in clothing. Some plants, such as manioc (a starchy root) and sweet potato, were first used in this region and then were introduced to the highlands and western coast. In fact, several important food crops of the Andean people may have had their origins in this region. The importance of the eastern foothills and tropical rainforest to Andean prehistory lies more in their contributions to earlier societies than in their economic importance to the Incas.