I spent many vacations between 1975 and 1992 visiting archaeological sites in Mexico. These included not only Mayan and Aztec, but also Totonac, Toltec, Zapotec, Mixtec, Olmec, and whatever peoples built the ruins at Teotihuacán. As a result, I developed a feeling for the strengths and weaknesses of these Meso-American peoples. This year I plan to visit Peru and acquaint myself with the Incas and the various peoples who preceded them in the Andes.
So far my researches have turned up some interesting results. First of all, the Incas had no writing—as such. Instead, they used colored threads of llama, alpaca, or cotton with knots tied into the various strands called quipus. We know which knots stood for the various digits in their base-10 numbering system, but have no idea how they managed to convey any kind of qualitative content, such as “Look out for that Lord Manco: He’s trying to pull a fast one on you.”
In contrast, the Mayans had a hieroglyphic language which is just now being understood, as well as a vigesimal (base-20) numbering system which is relatively easy to understand.
Whereas the peoples of Mexico had no animals they could use to either ride or carry or pull weights—remember: they did not have the wheel!—the Incas developed their own draft animals by breeding guanacos into llamas, alpacas, and vicuñas. Llamas could not bear human riders, but they could bear up to one hundred pounds of weight on their backs; and, unlike horses, they were comfortable about climbing stairs at high altitude. When fighting the conquistadores, the Inca learned to set up ambushes at places where one of their mountain roads turned into stairs. As the horses bunched up afraid to take the stairs, the Incas atop the ridge line would tumble huge rocks down upon their enemy.
Who were more advanced, the Incas or the Pre-Columbian peoples of Mexico? My feeling is that they were both remarkable. Where the Mayans excelled in writing, the Incas were great architects and built thousands of miles of roads—many of which exist to this day despite all the earthquakes that have occurred since they were built.
A good example of Inca ingenuity are the Intihuatanas, or “Hitching Posts of the Sun,” that are found at various sites, such as at Pisac and Machu Picchu. An Intihuatana was a stone that was carefully cut so that the Inca savants could note when the sun was approaching a solstice. An excellent discussion of the stone at Machu Picchu, together with angles and measurements, appears in a scholarly article by Dieter B. Hermann, which was translated into English and appears on the net as an Acrobat PDF file. The stone at Pisac was heavily damaged when a camera crane fell on it during the filming of a beer commercial in 2000. The Inca ruins can survive earthquakes, frosts, and thaws for whole centuries … but apparently not wayward humans.