The Andes are a good place to do naked-eye astronomy and that is part of why the systems there are so developed. The altitude thins the atmosphere, the dry season sky is cloudless for months, and the Milky Way passes close to the zenith, presenting its dust lanes at a convenient angle rather than low down through thick air.
Inca astronomy used all of it. The ceque system radiated forty-odd sightlines from the Coricancha at Cusco, marking shrines across the landscape, and several of them align on astronomical events. Pillars were built on the hills above the city to mark sunrise positions at the solstices, and the accounts describe officials whose job was to watch them.
None of this was theoretical in the Greek sense. There is no evidence of an Andean geometry of the heavens or of an attempt to model the motions, and the system is not less sophisticated for that; it is aimed at a different question. What it produced was an accurate working calendar in a region where getting the planting date wrong at altitude is a serious matter.
The serpent, the toad, the tinamou, the llama and the fox are the mnemonic layer of that calendar, and they survived the conquest, the extirpation campaigns and four centuries of Catholicism by being tied to work that still had to be done.