Teotihuacan Research Laboratory

Natural and Social Environments of the Central Mexican Highlands

by Research Professor Saburo Sugiyama

The central Mexican highlands, at an average elevation of roughly 2,000 meters above sea level, have a particularly rich natural environment characterized by alluvial plains and lakes surrounded by volcanic mountain ranges.

The temperate climate and an average annual rainfall of 450–900 millimeters mean that the area is well suited for agriculture.

The region’s wide variety of plants and animals living in the highly contrasting rainy and dry seasons environment were intensively exploited by ancient people.

Locally available materials like rocks and minerals, particularly obsidian, water from lakes, reeds, salt, wood and cacti were used for construction, tools, ornamentation, food preparation and rituals, enhancing the quality of everyday life.

The abundant plants and animals domesticated simultaneously at least since 5000 BC – such as corn, beans, squash, tomato, amaranth, chili peppers, cactus and chia, or dogs and turkeys – had been integrated into everyday life and helped maintained populous communities in the highlands.

The long interaction process between particularly diversified natural resources and people in this lagoon region was fundamental to the development of early social organizations.

The archaeological records suggest that the population and social complexity in the basin increased with the exploitation of resources and the development of other technological and organizational advances for ceramic production and stone craft industries, as well as market economies. Several populous villages were consequently established by the Middle Formative period, when intra- and interregional relations also became critical to the development of complex societies.

Large communities in the central highlands, such as Tlatilco, Las Bocas, Zohapilco and Chalcatzingo, already exhibit features from distant Olmec centers on the Gulf Coast. By the Late Formative, Cuicuilco, Tlapacoya and Cholula had become large nucleated villages or regional centers with monumental architecture. Cuicuilco, on the southwestern lagoon plain in the Basin of Mexico, became the first urban center during the Late Formative period, with 20,000 inhabitants.

Teotihuacán emerged as one of the most populous and stratified cities in the New World during the first two centuries AD. People living in the densely populated city for more than four centuries created an innovative religious ideology and political structure, invented new technologies and developed social organizations that were larger and more complex than previous ones.