The Aztecs

by Michael E Smith

  Table 3.2 Aztec archaeological sites and population levels in the Valley of Mexico.

  Category Early Aztec Late Aztec

  Type of Site

  Hamlet 258 986

  Small village 15 265

  Large village 4 89

  Regional center 14 41

  Supraregional center 0 2

  Ceremonial precinct 1 59

  Special-use site 1 57

  Indeterminate type 105 137

  Total sites 398 1,636

  Total population 175,000 920,000

  Data from: Sanders et al. 1979:184–5, 215

  The high Late Aztec population estimate produced by archaeological survey, 920,000, is consistent with the results of the historical demographic research summarized above. The survey results show that the large Late Aztec population was achieved through a rapid growth during a few centuries rather than a gradual sustained increase over many centuries. The Late Aztec period witnessed a great dispersion of population to all corners of the central Mexican highlands. The large size of the population raises several questions, including: what foods did the Aztecs eat, and how did they grow enough to feed three to four million people in highland central Mexico?

  The Aztec Diet

  Staple Foods

  Like all Mesoamerican peoples before and since, the Aztecs depended heavily on maize, or corn (Zea mays), for their sustenance.7 Maize is a remarkable plant whose domestication made possible the evolution of Mesoamerican civilizations. Maize exists in many different varieties, adapted to specific local conditions of soil and climate, and can grow nearly everywhere in Mesoamerica except for the cold high mountains. Indeed, the northern boundary of Mesoamerica as a culture area is usually defined as the northern limits of rainfall-based maize cultivation. A highly productive plant, with caloric yields among the highest of any major world food crop, maize is also high in protein. Animal sources of protein were in short supply in ancient Mesoamerica, so maize was an essential component of the diet.

  Maize was eaten in a variety of forms. Most common was the tortilla, a round, flat, toasted bread that has been a staple of Mesoamerican cuisine from the Classic period through the present. Tortillas were prepared by first soaking the shelled corn in an alkali solution (water with limestone, ashes, or another source of calcium hydroxide); next grinding the wet corn into dough on a metate or grinding-stone; then, shaping the tortillas by hand; and finally, cooking them on a clay griddle called a comalli. Instruction in tortilla-making was one of the fundamental lessons mothers taught their daughters (figure 3.2). Tortillas could be eaten fresh from the griddle, or they could be stored for later use, including meals eaten away from home by farmers, merchants, soldiers, or other travelers. Also popular were tamales, a more ancient, steamed food. Coarse maize dough was shaped into balls, often with some beans, chilis, or sometimes meat in the center, and then wrapped in maize leaves and steamed in a large clay pot. Other forms in which the Aztecs ate maize were atole, a thin gruel of fine maize flour in water flavored with chilis or fruits; pozole, a soup or stew containing large maize kernels (hominy); and elote or corn on the cob.

  Figure 3.2 Mother teaching her 13-year-old daughter to make tortillas (Codex Mendoza 1992:v.4:125:f.60r)

  Maize figured prominently in Aztec religion and thought. A number of deities were devoted specifically to maize and its growth (for example, Centeotl, whose name means “corn god,” and Chicomecoatl, the goddess “seven serpent”), and many rituals were carried out to propitiate these deities. Farmers requested a successful harvest by addressing the maize seeds formally before planting. Women thanked the maize before preparing it to eat, a practice that survives today in the folk ritual of Mesoamerican peasants. The symbolism of maize permeated Aztec thought, and people were often compared to the maize plant. For example, a person who had achieved honor was said to have “reached the season of the green maize ear.”8

  Beans were second only to maize in the Aztec diet. Like tortillas, they were served at every meal. Tomatoes, avocados, and several varieties of squash were also common, and squash seeds were eaten in several forms. A large variety of chili peppers gave spice and flavor to food. The seeds of the domesticated chia and amaranth plants were ground on a grinding-stone and eaten in several ways. The Aztecs shaped amaranth dough into small figures of the gods and ate them on ritual occasions. Amaranth leaves were also eaten as greens, and chia seeds were pressed to extract the oil.

  Nopal, the prickly pear cactus, was cultivated in the Valley of Mexico for its sweet succulent fruit and paddle-shaped leaf, which is a tasty green vegetable once the spines are removed. The maguey plant, a member of the Agave family, was cultivated for a number of uses. The fresh maguey sap was a nutritious beverage and, when allowed to ferment, became pulque or octli, the only alcoholic drink known to the Axtecs. Maguey and pulque were sacred to the Aztecs and had their own deities. A number of other products were derived from parts of the maguey plant: rope, textiles, nets, bags, and sandals were made from its coarse fibers, sewing needles from its spines, and medicines from the sap (see chapter 4).

  Animal Foods

  Dogs, turkeys, and the Muscovy duck were the only domesticated animals in ancient Mesoamerica. All were used for food, but they made only a minor contribution to the Aztec diet. This contrasts sharply with the ancient civilizations of the Old World, which exploited a variety of domesticated animals for food, fiber, and work as draft animals. The Aztecs also fished and hunted wild game, but again these sources of food were limited. After more than a millennium of urban civilizations with high populations, central Mexico no longer had significant reserves of game that could be used by the Aztecs. Archaeologists do find the bones of fish, deer, rabbit, iguana, dog, turkey, and other animals in Aztec domestic trash deposits, but rarely in dense concentrations. Meat from large animals was a minor part of the Aztec diet.

  Early Spanish observers noted the widespread use of insects among the Aztecs, including ants, grasshoppers, maguey worms, and jumil bugs. Insects are high in protein, tasty, and often could be harvested in large numbers. The Aztecs also gathered great amounts of blue-green spirulina algae (Spirulina geitlerii) from the surface of the lakes. This algae, known as tecuitlatl, is extremely high in protein, grows rapidly and abundantly, and is easy to gather with fine nets. Bernal Díaz del Castillo said of it, “the fisherwomen and the men . . . sell small cakes made from a sort of weed [algae] which they get out of the great lake, which curdles and forms a kind of bread which tastes rather like cheese.”9 The Spanish soldiers and priests had a low opinion of the palatability of this algae, but it was much prized by the Aztecs. The Aztecs also gathered a wide variety of wild plants for food and medicinal purposes.

  Nutritional Status

  The nutritional status of the Aztecs has been debated for a number of years. Some authors, pointing out the low level of animal protein in the Aztec diet and the large size of the population, argue that the Aztecs (or at least the commoners) must have been severely malnourished. In an extreme version of this argument, the unlikely suggestion has been made that the Aztecs resorted to cannibalism on a large scale to make up protein and calorie deficiencies.10 The notion that the Aztec diet was poor has been countered by analyses of the composition of Aztec foods, which show that for the most part the diet was nutritionally adequate. Whether or not sufficient quantities of food were produced in central Mexico to meet the needs of the burgeoning Aztec population, however, is a more difficult question to answer.

  Maize was the key to the nutritional success of the Aztec diet. Most traditional diets around the world depend on low-protein staple grains (such as wheat or rice) to provide the bulk of the calories, but the grain must be supplemented by animal foods that are high in protein. As mentioned above, maize is relatively high in protein for a grain, but by itself is not a complete protein since it does not supply all of the essential amino acids that the human body needs. The ancient Mesoamericans worked out two cultural practices that, when combined, provided
them with a complete protein source and greatly reduced their need for meat.

  For a food to be a complete protein (i.e., an adequate source of protein for human metabolism), it must supply all 11 of the essential amino acids. Animal flesh is a complete protein, which is why most cultures rely on meat for their protein needs. Maize is high in most of the essential amino acids, but several, including lysine and tryptophan, are chemically bound and not available if the maize is eaten unprocessed. Soaking the shelled kernels in an alkali solution both frees the tryptophan and adds calcium to the mixture.11 Beans are high in lysine. When beans are eaten together with lime-soaked maize, one has a complete, plant-derived protein source. The Mesoamerican preference for maize and beans at every meal has a solid nutritional basis.

  How did these practices originate and become fixed cultural patterns? We can only speculate. Mesoamerican farmers, in the past and today, let the maize dry out and harden in the field before harvesting it in order to store it for the coming year. The hard kernels must be soaked in water to soften them before grinding. Somehow, it was discovered that adding chemical lime to the soaking water, most likely in the form of powdered limestone, improved the maize. I have asked modern Mesoamerican peasant women why they soak the maize before cooking it, and their answer is that the tortillas don't taste right if the maize is not lime soaked. The Aztec ancestors of these women five centuries ago probably would have said the same thing.

  Other components of the Aztec diet provided important nutrients as well. For example, chili peppers are high in iron, riboflavin, niacin, and vitamins A and C; chia has high amounts of calcium, phosphorus, and iron; beans are high in niacin; and many of the wild herbs and spices used by the Aztecs are high in calcium and vitamin A. Without the benefit of modern nutritional knowledge, early Mesoamerican peoples managed to work out an adequate diet that suited their environment, and by the time the Aztecs arrived, these patterns were deeply ingrained cultural practices.

  The Aztec diet provided adequate amounts of protein and other key nutrients, but were their farmers able to produce enough to feed a population of several million? An important concept here is “carrying capacity,” or the total population that a particular environment can support, given the types of crops and farming methods in use. Because the measurement of ancient carrying capacity combines many difficult estimates (e.g., human nutritional requirements, the nature of past environments, ancient crop yields, the technology and organization of labor used in farming and hunting), the whole endeavor is somewhat controversial. Nevertheless, the available evidence suggests that the Aztec population had reached or exceeded the carrying capacity of central Mexico. The Aztecs could easily feed themselves in good years, but when yields were poor, owing to low rainfall, early frosts, or other periodic environmental fluctuations, the Aztec agricultural system did not produce sufficient food to feed adequately the entire population.12 During the final century of Aztec society, a number of famines and years of poor harvests were reported, and the famine of 1450–1454 was disastrous. How did the growing Aztec population attempt to meet its subsistence needs?

  Farming Systems

  Agricultural Intensification

  The intensification of agricultural practices was one of the most direct responses to the Late Aztec population explosion. It is also one of the most archaeologically visible responses. Agricultural intensification refers to changes in farming in which additional energy is invested in agriculture in order to secure higher yields from a given unit of land. Nonintensive or extensive agricultural methods, such as slash-and-burn farming or simple rainfall cultivation, are not highly productive in terms of yield per area, but are energy efficient because they do not require large investments of human labor. Extensive agriculture is adaptive where the population density is low and high yields are not necessary to meet subsistence needs. More intensive agricultural methods, such as heavy weeding, fertilization, or irrigation, provide greater amounts of food per area under cultivation, but require that a lot more work be expended in farming.

  The intensification of agriculture is a process that goes hand in hand with social change. As societies evolve and their populations grow, they require more food from the land, which forces farmers to intensify their methods. The development of social stratification and the state also stimulates intensive agriculture. Farmers must produce enough to meet the tax demands of the government and rent payments to nobles, as well as their own subsistence needs. All ancient civilizations relied upon one or more forms of intensive agriculture.13 In the Aztec case, simple rainfall agriculture was supplemented by terracing, irrigation, raised fields, and houselot garden cultivation. None of these intensive methods was new; they all dated back to earlier Mesoamerican civilizations. What was unique about Aztec agriculture was the degree of intensification, which transformed the countryside from its natural condition into a cultivated cultural landscape with little empty or wild land left.

  Friar Sahagún described the activities of the Aztec farmer as follows:

  The farmer . . . is bound to the soil; he works – works the soil, stirs the soil anew, prepares the soil; he weeds, breaks up the clods, hoes, levels the soil, makes furrows . . . He sets the boundaries; . . . he works [the soil] during the summer; he takes up the stones; he digs furrows; he makes holes; he plants, hills [up the soil], waters, sprinkles; he broadcasts seed; he sows beans, provides holes for them . . . fills in the holes; he hills [the maize plants], removes the undeveloped maize ears, discards the withered ears . . . gathers the maize, shucks the ears, removes the ears . . . 14

  Rainfall cultivation that involved some fallowing of the land was called tlacolol. The basic agricultural tool was a flat, wooden digging stick called a coa, which was used to turn over and perforate the soil. After the harvest, the maize was dried and and stored in shelled form in granaries that resembled those used by modern peasant farmers (figure 3.3). At the start of the Early Aztec period, most farmers practiced extensive rainfall cultivation. As populations grew and city-states expanded their control, more intensive methods were applied. Not every field could be transformed by intensification, however, and rainfall cultivation continued to be used in many parts of central Mexico.

  Figure 3.3 Traditional maize granary (cuexcomatl) used by modern rural farmers in the state of Morelos (Florescano and Moreno Toscano 1966:cover; drawing by Alberto Beltrán)

  Farming the Hills

  Central Mexico is mountainous, but the Aztecs put the gently sloping hillsides to good use. They constructed many miles of stone terrace walls to create level planting surfaces and turned otherwise unusable hillslopes into productive farm fields. Remnants of ancient stone terrace walls are found throughout the Aztec territory, and in some areas, Aztec terraces have been maintained or rebuilt and are still in use today. The Aztecs built three types of terraces, each adapted to different environmental conditions: hillslope contour terraces, semi-terraces, and cross-channel terraces.15

  The most common type of terrace – hillslope contour terraces – had stone walls that ran parallel to the contour of the slope (figure 3.4). The stones were piled up by hand, and the terrace behind the wall was filled in by digging into the hillside or by relying on natural soil erosion from uphill. Today the archaeological remnants of Aztec terrace walls are rough stone alignments rarely having more than a single course or layer of stones. In comparison with the better-known Inca agricultural terraces of the Andes Mountains, Aztec stone terraces were smaller and built of rougher stones with simpler masonry techniques. Whereas the carefully constructed Inca terraces often extended in parallel rows for hundreds of meters, Aztec terraces typically had an irregular layout, sometimes with a somewhat haphazard look. They do not show the hand of central planning.

  Figure 3.4 Aztec agricultural terraces at Cerro Texcotzinco in the Valley of Mexico. These terraces, used in the 1400s, were irrigated with water from a spring. The saddle between the hills at top right is an aqueduct that carried the water (photograph by William E. Dool
ittle; reproduced with permission)

  On more gentle slopes the Aztecs used low terrace walls made from long lines of maguey plants grown close together. Archaeologists call these semi-terraces. The maguey plants held soil erosion in check, creating level planting surfaces on which maize and other crops could be cultivated. The maguey themselves could be exploited for fiber and pulque. Cross-channel terraces or check-dams were built across streambeds in the bottoms of ravines, perpendicular to the stream. As the water flowed over the walls, silt and other sediments carried by the stream were trapped behind the stones to create a level surface. As deposition continued season after season, farmers gradually built the walls higher and the new field surfaces expanded greatly in area. Although check-dams were built in small increments over a period of years, the result could be an impressive stone terrace wall holding back a large level field. I excavated check-dams at the site of Cuexcomate (in Morelos) and found walls over 2 m high. They had been constructed over a long period of time and used for many decades (see discussion below).

  Farming the Valleys

  Irrigation was another method of intensive agriculture used by the Aztecs.16 In contrast to terracing, which opened up previously unusable land to cultivation, irrigation was applied to already-farmed valley soils to make them more productive. This was done by extending the rainy season (i.e., watering fields before the onset of the summer rains) and by providing additional water to crops during the growing season to supplement the natural rainfall. Although irrigation technology had a long history in central Mexico (it was very important at Teotihuacan), the Aztecs built canal systems that were both larger and more sophisticated than earlier endeavors.