The Incan society was responsible for a number of discoveries that are still relevant to us today, despite being extremely isolated from other cultures who may have influenced them.
Inca Discoveries in Medicine:
According to the testimony of Human Poma, an Incan medicine man interviewed in the 1550s, the Incas believed that diseases were caused by supernatural forces, but their treatments of herbs and minerals were based on strikingly scientific observations of their reactions. They understood the human immune system and how to strengthen it. Their doctors all trained in one central medical school in the Incan Capital, Cusco, for several years each, and regularly performed surgery. Records suggest their skull surgery survival rate was around 90 percent, impressive even by today's standards.
Inca Discoveries in Architecture:
Mention the Incas to most people, and the first images that may come to mind are the imposing geometric pyramids with which they came to be associated. These vast ziggurat-like structures are created without mortar of any kind, and the stones are cut so accurately as to fit together snugly enough to support the building. Mortar is usually the first material to decay over time, often resulting in the collapse of an ancient structure. Architects and archaeologists attribute the high standard of preservation seen on Inca monuments to this innovative building method.
Incan Inventions in Farming:
The steep hillsides and dry soil that surround the Andes are not ideal for farming, so as the Inca society grew larger, methods were developed to expand their food supply. The Incas developed an innovative irrigation system to guide water uphill, feeding their farms on the upper hillsides, where direct sunlight was strongest. The aqueducts they used to guide the water relied once again on their building skills. The angles used in these structures need to be perfect in order for the flow of water to work, something that many engineers struggle with even today.
They also were one of the first societies to use freeze-drying as a method of food preservation. Their home in the Andes experiences extremely hot temperatures during the day and sub-zero temperatures at night. Food would be left out overnight for the moisture to freeze, and then ice crystals were squeezed out in the morning. By the time the food warmed in the sun, all of the moisture was evaporated and the food preserved.
Inca Invention of Archiving:
When Hiram Bingham, the American Explorer, discovered the ruins of Machu Picchu in 1911, the local tribal leaders explained the Quipu archiving system to him. These bundles of knotted yarn were used to record information. Initially, archaeologists thought they were used to record numerical data, with different string lengths and knot positions representing different values. Though they have never been deciphered, some scientists believe the Quipu may also hold historical or anecdotal information about tribes, families and experiences.