The tougher the constraints, and the more hostile the environment, often the more innovation and creativity flourish. This is certainly true of the Incas, whose empire in the Peruvean Andes was ended by the Spanish invasion and conquest in around 1530. The story of Incan innovation is nicely documented in a recent Discovery Channel program.

The Andes Mountains have peaks higher than the highest mountain in the American Rockies. The Incas lived at elevations of around 4,000 m. Their descendants today have larger hearts and lungs than Americans or Europeans as a result. 

How do you feed your people, in a cold mountainous region whose weather is notoriously unstable? By growing food.   But how, on steep mountain slopes? Answer — terraces. The Incas perfected terracing — creating flat stepped areas on steep mountain slopes that resisted erosion and on which crops could be grown. They brought the soil from afar and it remains fertile to this day. They used guano (bird droppings) for fertilizer and protected the birds that supplied the guano. They were the first to plant potatoes, a vegetable brought from Peru to Europe by the Spanish, and developed more than a hundred varieties. Agronomists claim as many as half the vegetables we cultivate and consume today originated with the Incas. The Incas developed many varieties of maize (corn), also imported later to Europe. The Incas used medicinal herbs. They knew, for instance, that quinine was effective against malaria.

How do you ensure an ample water supply? The Incas built irrigation channels, diverting and even straightening whole rivers. How do you know what plants to grow, and how to grow them? By experimenting. The Incas built a remarkable experimental farm, in the shape of a huge terraced bowl. The bowl covered several temperature and climate ranges, from bottom to top. The Incas, who had no written language, were skilled mathematicians nonetheless and had a system for recording data based on knots tied on ropes. They  placed water containers at various elevations in their experimental ‘bowl’ and then measured the rate at which the ice in the containers, frozen during the cold nights, thawed and became water. 

Machu Picchu, discovered by an American explorer, is known as the Lost City of the Incas. Its elevation is 2,430 m.   It was completed in the year 1462, then abandoned a century later, probably because its inhabitants were wiped out by smallpox brought by the Spanish, and to which the Incas had no natural resistance. Today Machu Picchu is a popular tourist site. Some of its buildings reflect the Incas’ amazing skill at building with enormous stones, transported across the mountains for huge distances.