Final answer:
Cylindrical mills were not used in ancient central America due to existing practices with simple tools like mortars and pestles, material and environmental limitations, and a focus on small-scale production suited to local conditions.
Step-by-step explanation:
The question about why cylindrical mills were not used in ancient central America? can be tied to several factors relating to the technological, material, and economic contexts of Pre-Columbian Mesoamerican societies. First, the traditional indigenous methods of processing grains involved tools like mortars and pestles or other simple stone tools. These approaches were adapted to the small-scale agricultural systems in place and the social structure of the communities, which tended to focus on household-level production. The physical environment, availability of materials, and the labor provided by the community members impacted the evolution of tools and buildings. For instance, round homes in the region were made of mud and stone and featured thatched roofs. These materials were locally sourced and well-suited to the climate, providing coolness on hot days and warmth during cool nights.
Moreover, the absence of domesticated animals that could handle heavy weight in the Andean regions meant that the wheel was known but not utilized for transport, highlighting how environmental factors influenced the development of technology. Ancient Mesoamericans had sophisticated cultures, with the Olmec civilization influencing later Mesoamerican societies in architecture, agriculture, and ritual practices, but milling techniques remained relatively simple due to these various constraints.