Chapter II—
Indian Food Production and Consumption in Central Mexico before and after the Conquest (1500–1650)

1

That the Spanish conquest of central Mexico meant sweeping and cataclysmic change for the natives has been self-evident for centuries. That such sweeping change occurred in native production of food and in diet during the first century and a quarter after the Conquest is far from self-evident. In the 1930's and early 1940's the topic of food production and consumption before and after the Conquest attracted a good deal of attention, perhaps the most distinguished study forming part of the long series of inquiries on the Valley of E1 Mezquital by Miguel Othón de Mendizábal, published posthumously in 1947.^[1] Since the Second World War the topic has attracted relatively less attention, as inquiry has tended to focus upon current food production and levels of nutrition. The many community studies usually contain inquiries of this kind. This change in emphasis in part undoubtedly reflected the growing concentration of the government and of anthropologists within and without the country upon contemporary problems and upon improvement in existing standards of living. In part, however, it also may have reflected an opinion that in terms of materials

[1] Miguel Othón de Mendizábal, "Evolución económica y social del valle del Mezquital," in Obras completas , VI, pp. 7–195. See also Nathaniel Whetten, Rural Mexico , pp. 304–316.

and the knowledge available, inquiry into food production and diet immediately before and after the Conquest had approached a limit in yield of further insight.

Yet since the 1930's considerably more historical sources have become available, and new understanding from scientific inquiry has continued to accumulate. Mendizábal had available the greater part of the Relaciones Geográficas known to be extant, as well as a considerable body of other materials. Since his death many of the remaining extant Relaciones Geográficas have been published, and access to those in manuscript has become much easier through use of microfilm.^[2] Perhaps more important, a very substantial body of new material has come to light in the tribute assessments of Indian towns, and continuing inquiry has taught us much more about the nature and meaning of the sources.^[3] We have also learned a great deal more about changes in land use in central Mexico.^[4] At the same time that the body of historical material available to us has increased, our general knowledge of human nutritional needs has also expanded, especially as regards situations of undernourishment and actual famine. The first scientific study of the effects of famine was a product of the First World War and its aftermath. The Second World War stimulated inquiries that have vastly extended that initial study.^[5] In addition, historical inquiries on food production and nutrition in other areas during past epochs have continued to contribute new information that, fragmentary though it remains, nevertheless begins to permit us a basis for comparative judgment.^[6] Accordingly we now may inquire,

[2] For a bibliography of published and manuscript Relaciones Geográficas, see the essays by Howard F. Cline, "A Census of the Relaciones Geográficas of New Spain, 1579–1612" and "The Relaciones Geográficas of Spain, New Spain, and the Spanish Indies: An Annotated Bibliography," in HMAI , XII, pp. 324–369 and 370–395.

[3] Here perhaps the key publications have been Mexico, AGN, El libro de las tasaciones de pueblos de la Nueva España, Siglo XVI , and José Miranda, El tributo indígena en la Nueva España durante el siglo XVI . See also the discussion in Cook and Borah, Essays , I, chap. 1.

[4] Perhaps most notably Lesley Byrd Simpson, Exploitation of Land in Central Mexico in the Sixteenth Century , but also two of the studies of Sherburne F. Cook, The Historical Demography and Ecology of the Teotlalpan and Soil Erosion and Population in Central Mexico . Charles Gibson's The Aztecs Under Spanish Rule has brought to light and systematized a vast amount of information about the Valley of Mexico.

[5] See the discussion later in this chapter.

[6] Among the more notable of such studies are Nicolas Sanchez-Albornoz,Gastos y alimentación de un ejército en el siglo XVI según un presupuesto de la época , and the long series of studies published in Annales: Economies, sociétés, civilisations , frequently under the heading "Vie matérielle et comportements biologiques." See, for example, the articles in the bibliography by Frank Spooner, Frederick C. Lane, Jean-Jacques Hémardinquer, Michel Morineau, J.-P. Filippini, and B. Bennassar and J. Goy, eds. See also José Gentil Da Silva, Desarrollo ecónomico, subsistencia y decadencia en España , pp. 17–63; and Fernand Braudel, Civilisation matérielle et capitalisme (XV XVIII siecles), esp. pp. 97 et seq . Most of these studies are based on the records of formal provision for soldiers, sailors, people in charitable institutions, and wealthy families. The mass of the population, and especially the lower levels, had far less available. Braudel suggests 2,000 kilocalories a day as a fair estimate for the mass of the European population.

with the hope of gaining new insight, into questions deemed largely exhausted.

At the outset we require certain definitions and understandings of limitation. Food production obviously includes agriculture, but also all other activity that brings materials for human ingestion to availability through gathering, hunting, and fishing. Even warfare must be considered if the contending groups either eat each other, whatever the formal justification, or redistribute the results of each other's efforts at amassing foodstuffs. Similarly, one must take into account the distributive mechanisms inherent in political, social, religious, and economic structures that move foodstuffs, without warfare although frequently the result of previous warfare, from one stratum in the population to another or from one region to another. Tribute may loom large here. Consumption we must equate with nutrition, that is, the measurement of adequacy and kinds of intake in per capita terms. The best measure is probably in the kilocalories of physiologists, equal to the Calories of nutritionists, and in the further assessment of adequacy of intake of proteins, fats, carbohydrates, vitamins, amino acids, trace elements, and so on. In short, we must look at total intake in terms of adequacy of caloric intake, and further in terms of adequacy of elements necessary to sustain life and labor.

The century and a half covered by this study was a period of cataclysmic change in the religious, social, political, and economic life of central Mexico. We shall therefore examine patterns of food production and consumption as they existed just before the coming of the Europeans brought far more rapid and fundamental elements of change than were previously in operation. We shall also compare those patterns with what the opera-

tion of those elements of change wrought in the decades down to the middle of the seventeenth century.

Our area, central Mexico, unfortunately must be treated as a whole. It is approximately 514,000 square kilometers (about the size of Spain or of California), comprising regions of widely different topography and climate as well as peoples of considerable differences in technology and culture. The Spanish Conquest destroyed or reorganized many of the native states but did not erase the differences, which have since lessened under the erosion of time and operation of new cultural influences, but in many instances are still perceptible. Ideally, treatment should be by discrete regions, but with the possible exceptions of the Valley of Mexico and that of E1 Mezquital, we still do not have enough information for such treatment. Yet, thanks to the efforts of scholars, we have considerably more than we did three or four decades ago. Our essay, therefore, as all essays on this topic must be at this time, is an assessment of highly tentative nature.

2

On the eve of the Conquest, central Mexico had a very large population. We have estimated it at 25,000,000, the midpoint of a range of from 18,000,000 to 30,000,000. The rural population was probably denser at that time than in any period since. Even today, when the total of population stands higher and is rising, a far greater proportion of it is concentrated in large cities. We have further estimated the average density of aboriginal population at 49 persons to the square kilometer, or 125 to the square mile.^[7]

The agriculture upon which this population depended for its existence rested technologically upon the digging stick in its various forms as the basic instrument for cultivation. This implement made possible exploitation of land and slopes that could not be cultivated with the European plow introduced in the sixteenth century, and even less with present-day machinery. The basic systems of cultivation were various. On the coasts and intermediate slopes, the Indians cleared land by

[7] See Borah and Cook, The Aboriginal Population of Central Mexico on the Eve of the Spanish Conquest , pp. 88–90; Mexico, Dirección General de Estadística, Anuario estadístico de los Estados Unidos Mexicanos, 1970–1971 , p. 30, table 2.3.

felling or girdling and then burning off bush or forest, planted crops (usually two a year) for a period of two to five years, and let the land revert to wild growth in order to recover its fertility and eliminate weeds. Angel Palerm calls this the system of roza , but it is as frequently known as the slash-burn or swidden technique. It corresponds to Ester Boserup's forest fallow, with its practice of relatively long periods between cultivation. At higher altitudes or in dryer areas, where woody growth develops more slowly and the natural growth could not recover rapidly on land left fallow, a similar system of milpa is called barbecho by Palerm. The intervals of fallow are markedly shorter; the land tends to be cropped only once a year, except in unusually favorable conditions. This type of land use corresponds clearly to Ester Boserup's bush fallow. Although the systems of roza and barbecho appear to be almost alike, the difference in climate dictates very different conditions and the intervals of fallow are markedly different. The barbecho system permits a denser occupation of land.^[8]

What in Boserup's conceptions would be called permanent cultivation—that is, without long periods of reversion to natural growth—was also practiced by the Indians of central Mexico in a variety of forms. Where soil and climate favored the practice, the land was cropped annually or more often on the basis of rain and retained moisture. Land of considerable slope might be terraced to improve conservation of soil and moisture and yield. Perhaps the most notable instance of extensive terracing was in the area around Chalco, famous as a pre-Conquest producer of maize. An even more favorable development appeared where there was a supply of water available by conduction through canal or channel, or by raising it from wells or lakes. The Indians used the water for irrigation to insure steady yield, and in the lower-lying areas especially, two crops or even more a year. A special variant was and is the chinampa , often described

[8] A good description may be found in Gordon R. Willey, Gordon F. Ekholm, and René F. Millon, "The Patterns of Farming Life and Civilization," in HMAI , I, pp. 446–498; and in Angel Palerm, "Agricultural Systems and Food Patterns," in HMAI , VI, pp. 26–52–which, although a description of present-day practice, is easily adjusted to pre-Conquest times. See also Palerm's essay, "La base agrícola de la civilisación urbana prehispánica en Mesoamérica," in Angel Palerm and Eric Wolf, Agricultura y civilización en Mesoamerica , pp. 65–108; and Ester Boserup, The Conditions of Agricultural Growth: The Economics of Agrarian Change Under Population Pressure, passim .

as a floating garden but actually a manmade plot of brush and mud in a marshy area or shallow part of a lake, that can be watered from the lake or marsh and is capable of steady, prolific yield. The chinampa is really a further development of a widespread Indian practice of raising mounds or ridged fields for cultivation in marshy soil or on lands subject to flooding. Wherever found, their presence indicates pressure of population upon the supply of cultivable land.^[9] As yet there has been little inquiry to detect the possible presence of the more widespread form of raised mounds or ridged fields in central Mexico.

In general, land on the plateau yielded one crop a year, the yield varying with fertility of soil and rainfall or irrigation, whereas land at the lower altitudes more normally yielded two crops. Irrigation and the chinampas made possible multiple crops, the chinampas coming close to the garden cultivation of the Mediterranean or the Far East. In the Valley of Mexico the chinampas benefited from a remarkable system of control of water that is only now being studied with any care. Its functions were to control water levels and to prevent the saline waters of Lake Texcoco from contaminating other lakes and the chinampas in them.^[10]

The crops that were raised under these varying systems^[11] were maize, regarded as the staple, an unusually productive crop, more so than wheat; beans, perhaps best described as frijoles to avoid the ambiguities in the English term; squash; chiles of many kinds; chía; and huautli. These last two were often gathered from plants growing wild rather than cultivated. Huautli is thought by Eusebio Dávalos Hurtado and Jonathan Sauer to have been utilized especially for ritual purposes. In addition, the more arid areas supported stands of cactus (no -

[9] See references in note 8; additionally, Kent V. Flannery et al., "Farming Systems and Political Growth in Ancient Oaxaca"; Robert C. West and Pedro Armillas, "Las chinampas de México: Poesía y realidad de los 'Jardines Flotantes'"; and Armillas, "Gardens on Swamps."

[10] Palerm, references given in note 8 plus Obras hidráulicas prehispánicas en el sistema lacustre del valle de México, passim .

[11] The following paragraphs are based upon: Eusebio Dávalos Hurtado, "La alimentación entre los mexicas"; Enrique Beltrán, "Plantas usadas en la alimentación por los antiguos mexicanos"; the answers in the Relaciones Geográficas 1577–1585, published and manuscript; Bernardino de Sahagún, Historia general de las cosas de Nueva España, passim , but esp. II, pp. 65–70, 134–159, and 317–492; Francisco Hernández, Historia natural de Nueva España, passim; and Jonathan D. Sauer, "The "The Grain Amaranths," pp. 564–582.

pal ), which yielded cactus apples (tunas ), and stands of agave (maguey ), again a versatile plant from which the Indians extracted juice for pulque and used the blades and heart for food. Use of wild stands shaded into cultivation for both nopal and maguey, the latter perhaps being more often cultivated. It was also an important source of fiber, used widely in the uplands for clothing as well as other purposes, but always inferior to the lowland cotton. There were root crops, but they were of lesser significance. The sweet potatoe (camote ), raised in the lowlands, was perhaps the most important. For central Mexico as a whole, Spanish reporting emphasized that the staple was maize, which was ground to dough for tortillas, to mush for tamales or atole, or was eaten in a wide variety of ways.

These products of field cultivation were supplemented by a wide variety of fruits and vegetables, some deliberately planted, some growing wild. The lists and references in the Relaciones Geográficas, in Sahagún, in Francisco Hernández, and in the accounts of many other writers, are long and embrace almost every edible fruit and plant, with the exception in most regions of the acorn.

The pre-Conquest Indians of central Mexico secured food of animal origin more from wild than domesticated animals. Honey they obtained from the stingless American bee; meat from Muscovy ducks, dogs raised and fattened for food, and turkeys.^[12] The list of domesticated animals is short, but the large expanses of water, forest, bush, and fallow land supported game and fish, as well as offering wild fruits and plants. Thus the products of agriculture could be supplemented by extensive hunting, fishing, and gathering. This pursuit, which was carried on at a very sophisticated level, yielded mammals, birds, fish, reptiles, amphibians, crustaceans, insects, worms—in fact anything that could be eaten, to the disgust of Spaniards. As Francisco López de Gómara commented, "they eat any living thing, even their own lice. . . . "^[13]

[12] There has been much doubt that the Mesoamerican Indians really had domesticated the turkey, but the declaration of the city council of Veracruz in its letter to Charles V, 10 July 1519, should be conclusive: " . . . y crían muchas gallinas como las de Tierra Firme, que son tan grandes como pavos." (Hernán Cortes, Cartas y documentos , p. 23.) See also M. de Cárcer Disdier, "Los pavos."

[13] Francisco López de Gómara, Historia general de las Indias , II, p. 400. See also the description of the foods offered in the marketplace of Tenochtitlán-Tlatelolco, ibid. , pp. 147–148.

Two sources of food have always been the cause of considerable comment. One was derived from the lakes in the Valley of Mexico, in which there was a strong development of algae. The Indians gathered these plants by scraping the scum off the rocks or collecting it from the water in nets, dried it and compressed it into cakes, which became an article of trade and food. However unappetizing and even revolting to Europeans, the blue-green cells furnished an excellent source of vitamins and carbohydrates. A similar use of algae is now being suggested as one solution to the increasing need for food, as the human population of the earth presses more severely upon known sources of nutrition. We should note that algae or "bloom" appear in lakes which are polluted by fertilizer and sewage, that is, by unusually large supplies of nitrates and phosphates. If the lakes, and especially Lake Texcoco, received heavy amounts of raw sewage from Tenochtitlán and other urban aggregations, one would expect the very heavy growth of algae, that in fact occurred. The Indians, with their skill in using any possible source of food, then ate the algae. The incidence of intestinal diseases from the polluted lakes must have been enormous.^[14]

The other source of food was cannibalism, an activity ritual or otherwise which has been much debated. From a strictly dietary point of view, it is undoubtedly true that for most of the population the ceremonial portions consumed of the sacrificial victims were so small that their addition to the annual food intake was completely negligible. On the other hand, for the upper classes, who benefited most from this type of nutrition, the addition of human flesh to an otherwise low-meat diet may have been of consequence. Indignant denials by some apologists are meaningless, because a nutritional craving is not necessarily apparent to the consciousness and could easily be masked by a highly developed ceremonial motivation.

The one potential source of food which seems to have been underutilized is the acorn, a surprising item in the long list of

[14] Hernández, Historia natural , II, pp. 408–409; Gibson, The Aztecs Under Spanish Rule , p. 141; Sahagún, II, p. 372; Toribio de B. Motolinía, Memoriales , pp. 327–328; Bernal Díaz del Castillo, Historia Verdadera de la Conquista de la Nueva España , I, p. 279; Gómara, II, p. 147; W. V. Farrar, "Tecuitlatl: A Glimpse of Aztec Food Technology"; and Edward S. Deevey, Jr., "Limnologic Studies in Middle America," pp. 226–228. Farrar identifies tecuitlatl as a member of Cyanophyta, or blue-green algae, probably now extinct. On algae, see further F. E. Round, The Biology of the Algae , pp. 72–73, 147–156, 211, 217, 219–225.

efficient use of available resources. Mexico is a major center of development of oaks, with more species than any other similar area. Oaks, black and white, deciduous and evergreen, grow throughout the country except in the regions of tropical rain forest or high aridity; all bear acorns varying from very small to quite large. In suitable areas, of which there are many, the production of acorns is certainly as prolific as in California.^[15] Yet in California the Indians before the appearance of Europeans made use of the acorns as a major source of food. The acorns were gathered, shelled, most often pounded to meal, the tannin then leached from the meal by pouring hot water through it, and the purified, sweetened meal made into mush or thin cakes, just like the Mexican atole, tamales, or tortillas. In other uses, the acorns shelled or unshelled were placed in river sand or mud so that the action of cold water could remove the tannin more slowly. The acorns were then shelled if necessary and roasted.^[16] This use of acorns extended into the Southwest, large parts of the rest of the United States,^[17] and into Mexico in times before the immediate pre-Conquest.^[18] It is therefore surprising to find that the Spaniards, who themselves were familiar with the use of acorns as human food,^[19] mention the presence of oaks and that the large supply of acorns would make excellent fodder for pigs, but do not mention their use by the Indians.^[20] The Relaciones Geográficas similarly mention the

[15] See the section on quercus in Paul C. Standley, Trees and Shrubs of Mexico , pp. 171–198. This section is actually by William Trelease and, although out-of-date as to classification of varieties, is nevertheless valid for our purposes. Trelease, citing V. Havard, "Food Plants of the North American Indians," asserts that acorns were widely used by the Mexican Indians. Havard (p. 118) actually refers to the Indians of the United States and adjacent parts of northern Mexico.

[16] Alfred L. Kroeber, Handbook of the Indians of California , pp. 87–88 et passim .

[17] Havard, "Food Plants," pp. 118–119.

[18] See Richard H. Brooks et al., "Plant Material from a Cave on the Rio Zape, Durango, Mexico," pp. 360–362 and 367. The studies in the Valley of Tehuacán have turned up very little sign of use of acorns, but the region is too arid for much development of oaks. Douglas Byers and Richard S. MacNeish, eds., The Prehistory of the Tehuacan Valley , I, table between pp. 232–233, shows the scanty finds of acorns.

[19] See Gonzalo F. de Oviedo y Valdés, Historia general y natural de las Indias , I, p. 298, and his Sumario de la natural historia de las Indias , p. 213, both of which mention finding oaks bearing acorns in Panamá and Nicaragua, and the Spaniards' eating them.

[20] Sahagún, II, pp. 397–398 and all of 396–407. See also below.

presence of oaks and the supply of acorns, but almost never their use by the Indians.^[21]

It is true that the mention often is that the acorns, being small and bitter, were suitable only for pigs.^[22] On the other hand, the California Indians and others preferred the bitter acorns as having more character,^[23] and removal of a noxious or lethal element by leaching or other ways is a widespread American Indian cultural trait that extends from the cleansing of acorn meal to the preparation of farinha from the highly poisonous bitter manioc. The argument that cultivation of maize yielded a grain deemed far more satisfactory will not hold, since anything else that could be hunted, fished, or gathered was put to use in human nutrition. It is possible that the central Mexican Indians did indeed make use of acorns in the decades immediately preceding the Conquest, but that the rising and easier availability of other foods as population shrank led to abandonment of a more time-consuming alternate supply. Even that possibility seems unlikely, since the Relaciones Geográficas were prepared approximately sixty years after the landing of the Spaniards on the coast of central Veracruz, a rather short interval for the loss of all memory. In the end, we are forced to leave this matter with a question mark: we do not know.

Even with the omission of the acorn, the list of foods adds up to an easy basis for a rich and varied diet, fully supplied with human requirements in protein, fat, vitamins, and minerals, provided that the total caloric intake available to all the population was adequate and provided further that all parts of the population had access to the scarcer items, particularly those secured through hunting and fishing. Here regional differences

[21] The Relación de las minas de Temazcaltepec, 1 December 1579–1 January 1580, has a clear statement of the use of acorns, in the description of Texcaltitlán: "22. Los arboles que tiene Tescaltitlan en sus montes son enzinas, que algunas dan bellotas que las comen los naturales, y moliendolas hazen dellas tamales ques çierto genero de pan entre ellos. . . . " (Francisco del Paso y Troncoso, PNE , VII, p. 23.) On the other hand, see the report for towns around Jalapa in the Relación de Jalapa de la Veracruz, 10 October 1580, where the statement is: "Ay en este pueblo ençinas con bellotas y no se aprouechan de ellas . . . " (ibid. , V, p. 107) and variations on it (pp. 110 and 111–123). The reports on the occurrence of oaks and acorns may be traced through the answers to question 22.

[22] See, for example, the Relación de Tepeaca y su partido, 4–20 February 1580, ibid. , V, p. 35.

[23] Oral communication of field observation by Professor Martin Baumhoff, Department of Anthropology, University of California, Davis.

must have loomed large, since climate, fertility of soil, and the availability of resources for hunting and fishing varied greatly. The range would have been from the rich central Veracruz coast and Valley of Mexico to the arid Valley of the Mezquital. In this last, too, the role of maize as staple diminished greatly, to be replaced by the remarkably versatile maguey.^[24]

With respect to equable distribution of those food resources at the disposal of the total population, there is abundant evidence in reports of the sixteenth century that there were very substantial differences between the diet available to the nobility and in lesser degree to the merchants, artisans, and other favored groups at one extreme, and to the peasantry at the other. The nobility ate abundantly and well of all foods. In their diet, the products of hunting, fishing, and gathering made up for the scarcity of domesticated animals, and there was available an unusually varied choice of plants, grains, and fruits. The Relaciones Geográficas in reports from a number of towns stress the fact that the choicer products of cultivation and the more desirable results of hunting, fishing, and gathering were reserved to the upper classes.^[25] Within the upper classes there were obviously significant differences in supplies of food, based not merely upon status within the local society but also upon regional power relationships. The redistributive mechanism of the local political and class structure was modified further by the operation of tribute within the larger structures established by conquest, which moved substantial quantities of foodstuffs as well as nonedible commodities to the centers of imperial power. The most striking instance was the huge tribute levied by the Triple Alliance upon subject towns, to the enrichment especially of Tenochtitlán, but also of Texcoco and Tlacopan. In effect, the Valley of Mexico enlarged its supply of foodstuffs, particularly for its upper classes, by levy upon perhaps half of central Mexico. The Tarascan state in Michoacán must

[24] Mendizábal, "Evolución económica y social," Obras completas , VI, pp. 54–59 et passim , emphasizes the importance of the maguey and the impossibility of supporting the population in the Mezquital by raising maize.

[25] Sahagún, II, pp. 65–70 and 134–159; Oviedo y Valdés, Historia general , IV, pp. 248–250. Some examples of such declarations are: Relación de Mitlantongo, 12 November 1579; Relación de Mitla, 12 November 1581; Relación de Atlatlauca y Malinaltepec, 8 September 1580; Relación de Cuicatlán, 15 September 1580; Relacion de Teutitlán del Camino—in PNE , IV, pp. 79, 149–150, 171, 186, and 211 respectively; and Relación de Texcoco, 5 March 1582, in Joaquin García Icazbalceta, Nueva colección , III, pp. 40 and 49.

have had a similar distribution in favor of its upper class centered in Pátzcuaro. So long as imperial tribute did not strip towns too far, the local nobility were able to shift to their peasantry the loss through regional redistribution.^[26]

The peasants, who constituted the overwhelming bulk of the population, ate a much leaner diet of maize, beans, chile, and agave, but these staples too were supplemented by a wide variety of other foods. Fruits were abundant, and there were available such products of hunting, fishing, and gathering as were not reserved for the upper classes. There was a great variety of wild fruits, vegetables, nuts, berries, greens, roots, and the like, which could be gathered over the countryside. The peasants could obtain animal protein from smaller mammals and birds, together with the lower forms of the animal kingdom such as iguanas, snakes, lizards, amphibians, worms, and grubs. As we have already mentioned, even the algae in the lakes were utilized. A number of the Relaciones Geográficas state emphatically that just about everything edible was eaten.^[27]

This diversity is one key to the survival of a huge population. If we forget the esthetic aspects of the matter, we see that the Indians as a whole were exploiting in an amazingly efficient manner the total biomass of the environment, and that in terms of essential elements, vitamins, and protein they probably had enough, except in years of complete crop failure. Even then the deficiency was quantitative, not qualitative. Our own tendency to emphasize agricultural technology and to neglect natural productivity has led too often to an underestimate of the carrying capacity of a region. All that is needed is a population with the experience and the resourcefulness to utilize the reservoir which is there. A very simple technology is all that is required.

3

The matter of per capita caloric intake of the peasantry is more difficult, even in terms of countrywide generalizations. We have

[26] See the discussion in Borah and Cook, The Aboriginal Population of Central Mexico on the Eve of the Spanish Conquest , pp. 6–21, 60–71, et passim .

[27] For example, Relación de Nexapa, 12 September 1579; Relación de Piaztla, 2 January 1581; Relación de Atitalaquia y su partido, 22 February 1580–in PNE , IV, p. 42; V, p. 79; VI, p. 207. See the very explicit statement in Gómara, II, pp. 400 and 147.

no firm basis for estimating overall production and dividing it by the probable number of people. However, certain aspects of the problem can yield insight under discussion. One of these relates to the energy requirement of the Aztecs and kindred tribes in the conditions of their existence. A present-day European or American man of average size, doing moderate work, is thought to require 3,000 kilocalories a day. Women and children need correspondingly less, such that the mean may be near 2,500 kilocalories. It is very doubtful whether the aboriginal peoples of central Mexico got anywhere near this amount. There is, indeed, an increasing body of evidence suggesting that, except in unusually favorable circumstances, few people even in Europe enjoyed average daily caloric intakes that would correspond to present-day standards of nutrition.^[28]

In order to pursue further our examination of the dietary and metabolic status of the central Mexican Indians prior to the coming of the Europeans, we must first determine certain anatomical and physiological constants. These may be obtained with relative ease for a living population, but can be secured only by indirection and difficulty for a long-extinct people. The first of these magnitudes is simple body size, in its most elementary terms defined as height and weight. From these factors we may derive the probable basal metabolic rate and the caloric ration necessary to support it. Additional data are available concerning physical effort and expendable labor.

Estimates of body size for the pre-Conquest inhabitants of central Mexico must be drawn from three sources. The first is contemporary statements, which are surprisingly scanty. The earliest mention, the report of the city council of Veracruz to Charles V, describes the natives as of medium stature with well proportioned bodies.^[29] Gómara, presumably summarizing the testimony he gathered from Hernán Cortés and other conquerors in Spain after central Mexico was under Spanish control, makes almost the same statement: "of medium stature, but robust."^[30] The Anonymous Conqueror's statement is also close: "well-shaped, rather tall than short."^[31] The implications are

[28] Braudel, Civilisation matérielle et capitalisme , pp. 97–99; Ashtor, "Essai sur l'alimentation des diverses classes sociales dans l'Orient médiéval," pp. 1043–1053.

[29] Veracruz, 10 July 1519, in Cortés, Cartas y documentos , p. 23.

[30] Gómara, II, 398.

[31] [Anonymous Conqueror], Relación de algunas cosas de la Nueva España  . . . , p. 41.

that relative to the Spaniards of the time, the Indians were of average size and weight. Since by our standards the Spaniards of that time were small men, with an average height of perhaps 160 centimeters (5 feet 3 inches) and an average weight of perhaps 60 kilos (132 lbs.), the Indians can have been no taller and no heavier.

The second source of information on body size is the measurement of skeletons of the fifteenth and sixteenth centuries found in excavations in central Mexico. Here too our information is surprisingly scanty, but what there is of it yields reconstructed statures for males ranging from 1.59 to 1.64 meters.^[32]

A third method of estimate is by comparison with present-day conditions. It is possible that some change has occurred in the more than four centuries since the Conquest, particularly through nutritional betterment. However, in rural areas, among the Indians, dietary conditions are much the same as they were in the sixteenth century. Moreover, except in the North of Mexico (which lies outside our area of study) and among the mestizos, no increase in size has been noted, and certainly no decrease. We are therefore justified in thinking that body size among the rural indigenous population has not altered significantly since the time of Cortés.

There have been literally scores of investigations which have included measurements of the height and weight of groups of people all over the earth. It is manifestly impossible and also unnecessary to cite most of these. However, it is worthwhile to mention some of the data which concern the aboriginal inhabitants of both North and South America, with the emphasis upon Mexico. These figures have been compiled and are presented in condensed form in Table 2.1.

For height, the eighteen averages of adult males in Indian groups living north of central Mexico have a range of 161.1 to 174.9 and a mean of 166.5 centimeters. These values are as good as can be obtained with present-day anthropometric methods. The samples are adequate and the techniques satisfactory. For the set of twenty averages obtained for Indians in central Mexico, the analogous mean is 158.5 and the range from 154.2 to 163.4 centimeters. If the individual averages for each area, central Mexico and north of central Mexico, are compared

[32] Genovés T., "Anthropometry of Late Prehistoric Remains," in HMAI , IX, table 3 between pp. 40–41.

numerically, the value of t is 6.39. A very significant difference in height between the Indians of the two areas is therefore indicated.

There are in Table 2.1 sixteen averages for Maya groups in Yucatán and Guatemala. For them the mean is 156.0 centimeters. If t is calculated for the Maya against the central Mexican samples, it is found to be 2.83, a figure just at the 1% level of probability and hence definitely significant statistically. However, the Mesoamerican and South American samples may be compared by making an analysis of variance for the three aggregates, representing central Mexico, Yucatán, and South America. The value of F equals 1.30, a totally nonsignificant figure. Therefore, these reports as a whole show heights within a very narrow range, probably within the margin of error of sampling and measurement.

For the central Mexican group, in which we are particularly interested, the mean is 158.5 centimeters, but the variation is considerable. The Tarascans and some of the Nahuas are taller than the Otomí and the Oaxaca Indians. Nevertheless, the mean of the entire twenty samples must represent substantially the true condition. This mean may be taken as 159 centimeters, especially in view of the fact that the Nahua average is 159.8 for seven samples. In English units, 159 centimeters equals 5 feet 2 1/2 inches. The Nahuas would average one-half inch taller than the general mean.

With one exception, the averages for body weight of Mexican Indians shown in Table 2.1 are taken from the compilation by Marshall Newman.^[33] Those for central Mexico give a mean of 53.6 kilos, and those for the Maya 53.8 kilos. In order to check the consistency of this mean, Newman's formula may be employed: the ratio of the stature to the cube root of the weight equals a value which lies between 38.0 and 43.0. There are other formulas, but none are perfect, and Newman's is close enough for ordinary purposes. For central Mexico plus Yucatán, we get 42.1, a value which lies well within the prescribed range. Our final values for central Mexico are: height 159 centimeters, weight 53.6 kilograms.

These values relate to adult males. The other half of the adult population, the female, is universally smaller. The male/female

[33] Marshall T. Newman, "Adaptations in the Physique of American Aborigines to Nutritional Factors."

ratio of size can be approximated from some of the data given by various investigators, such as are presented in Table 2.2 for height alone. Clearly there is variation because of both sampling error and differences in body build. However, the average female/male ratio is very close to 92.5 (the female/male ratio is more convenient for use than its reciprocal). A very large sample of white Americans shows 92.7;^[34] Goldstein's series of Mexicans in several age groups over nineteen years averages 92.5.^[35] In view of the uniformity found in the published accounts, the pre-Conquest Mexicans can be regarded as differing little in this respect from those of the present day. Then, if the ratio is 92.5, the height of pre-Conquest females was 159 × .925, or 147 centimeters. The approximate average weight may be obtained by taking 92.5 percent of the average male weight: 53.6 × .925, or 49.6 kilograms.

In order to estimate the basal metabolism and hence the caloric requirements of a person having the dimensions just specified, we should know the surface area and the number of calories required per square meter of surface. It is true that much present-day research stresses the importance of body composition and utilizes fat-free body weight as readily as it does surface area. However, when we are dealing with an extinct population, and since we know absolutely nothing about the body composition of the pre-Conquest Indians, surface area provides a better criterion. We shall try both methods.

Without considering surface area, it is possible to calculate the probable basal metabolism directly from weight if one follows the prescription of Max Kleiber. Kleiber asserts that the interspecific mean intrinsic metabolic rate is 70 kilocalories per day per weight in kilograms to the three-quarters power.^[36] If this formula is applied to the average Aztec or Mixtec, as may be, the result is 70 × (53.6)^3/4 , or 1,387 kilocalories per day, or 57.8 kilocalories per hour.

The original formulation of the relation between surface area and height and weight was worked out many years ago by Dubois and is shown graphically in numerous standard texts of physiology and biochemistry. It represents a broad average for

[34] Howard W. Stoudt et al., "Heights and Weights of White Americans."

[35] Reproduced in Gabriel Ward Lasker, "The Age Factor in Bodily Measurements of Adult Male and Female Mexicans," p. 57, table 2.

[36] Max Kleiber, "Body Size and Metabolic Rate," p. 512.

most of humanity, and its validity for man has never been seriously attacked. Therefore we may use the relationship thus set forth with reasonable confidence that it applied to prehistoric as well as to living populations. A chart after Dubois is shown by Ruch and Patton^[37] and by Philip Bard.^[38] The closest it can be read for 159 centimeters and 53.6 kilos is 1.54 square meters, plus or minus 0.02 square meter. Since this error is less than 1% it may be ignored.

A tabulation by Bard, based on data from Benedict and from Rubner, indicates that 41 men with an average weight of 53.4 kilos produce 914 kilocalories per square meter of body surface in 24 hours; the total heat would be 1,408 kilocalories per day.^[39] Another formulation shows, according to the Aub and Dubois standards, that a man between 18 and 30 years of age produces about 40 kilocalories per square meter of body surface per hour.^[40] Hence 40 × 24 × 1.54 = 1,478 kilocalories per day. Since these data have never been controverted in principle, we may conclude that if the pre-Conquest Mexican Indian adult men of 14 to 40 years averaged 159 centimeters and 53.6 kilos, then their mean basal metabolic rate was approximately 1,425 kilocalories per day (1,425 is the mean of 1,387, 1,408, and 1,478).

It should be emphasized that the values just given relate only to the average adult man under basal conditions. If we are concerned with populations, we must know the comparable figures for other components, specifically women and children. For adult women our estimate of body size indicates a height of 147 centimeters and a weight of 49.6 kilos. The closest reading of the Dubois graph gives a surface area of 1.41 square meters. Thus the metabolic rate of women is close to 36.5 kilocalories per square meter per hour, and the daily rate is 1,235 kilocalories.

The basal metabolism of children collectively is much more difficult to assess, for several reasons. First, the number of children varies in different populations; second, the intrinsic metabolic rate varies with age, i.e., the heat production per unit

[37] Theodore C. Ruch and Harry D. Patton, Physiology and Biophysics , p. 1045, fig. 12.

[38] Philip Bard, ed., Medical Physiology , p. 482, fig. 171.

[39] Ibid. , p. 480, table 37.

[40] Ibid. , p. 478, table 31.

weight decreases after late infancy; third, the total metabolism increases with increase in size.

With respect to the proportion of children in the population, we do not, of course, have any direct information concerning the situation prior to the Conquest. However, there is a considerable body of evidence for the colonial period, particularly the late eighteenth century. Furthermore, we know that the demographic status of the central Mexican population was much the same in both the fifteenth and the eighteenth centuries. Both must have been characterized by high birth and death rates. Both were under strong pressure toward increase. Hence the proportion of children in both must have been more or less similar. In a previous essay, our examination of data for the late eighteenth century made it clear that, in spite of numerous ethnic and geographical differences, the number of children in Mexico under the age of sixteen years approached 45% of the total population.^[41] In the absence of any contrary evidence, the same proportion reasonably may be assumed for the population in, let us say, 1518.

Since body size and metabolism both vary enormously with age, and since we have little refined data pertaining to the distribution of these magnitudes in the youthful population, some type of short-cut is mandatory. The simplest procedure is to take the features characteristic of the median age in the range 0–16 years, and let them stand as an average, although a very crude one, of all children. In a primitive population of this sort, if children, metabolically speaking, are all those under 16 years of age, the median can be estimated from the late-eighteenth-century data.^[42] The value lies somewhere near the age of 6 years.

The size and the intrinsic metabolic rate of 6-year-old children can be calculated only by the use of data derived from present-day American or European sources. When applied to pre-Conquest Mexican Indian children, the result is likely to contain a relatively large error. Hence we can arrive at only a crude approximation, although even an approximation is preferable to nothing. According to Wohl and Goodhart, 6-year-olds of the smallest size, both boys and girls, are 42.8 inches tall and have an average weight of 38.75 pounds. We select the smallest

[41] Cook and Borah, Essays , I, pp. 201–299, esp. p. 255 et seq .

[42] Ibid. , pp. 257–259.

size (5th centile) in order to approach as closely as possible the probable size of Mexican children.^[43] Then, converting units to the metric system, we have 108 centimeters in height and 17.6 kilos in weight.

We employ next the Dubois graph, with extrapolation where necessary, to estimate the body surface at 0.7 square meter. Closer estimate is not feasible. Finally, the metabolic rate is found by reference to the table in Ruch and Patton, according to which for 6-year-old boys and girls a mean of 51.7 kilocalories is produced per square meter per hour.^[44] Then the metabolic rate per child becomes 869 kilocalories per day, say 870 kilocalories. An error of plus or minus 10–20% will have to be allowed, but a working mean of 870 kilocalories per day is reasonable.

We are now in a position to make an approximate estimate of the metabolism of the population. An adult male produces per day 1,425, an adult female 1,235, and a child 870 kilocalories. According to our data already cited, there are 55% adults (27.5% adult males and the same percentage of females) and 45% children. Therefore, 1,000 people produce 275 × 1,425 plus 275 × 1,235 plus 450 × 870 kilocalories. The total is 1,123,000 kilocalories per day, or 1,123 per person. This would be the basal value, the minimal amount needed to maintain organic integrity, with no excess even for the easiest kind of physical activity or for the digestion of normal food.

In order to evaluate the caloric requirement in daily life of the pre-Conquest central Mexican Indians, we have to know something about the level of their physical effort. In turn, it is necessary to equate this activity with the increase caused thereby in the metabolic rate over the basal value. We shall examine the second phase of the problem first, and do so by considering data derived from study of present-day populations.

There have been a great many investigations of the effect of various types of physical exertion upon the energy flow through the human organism. These studies have one aspect in common: they all pertain to present-day subjects who are of European-American physique and who subsist according to what are considered nutritionally adequate standards. For the central

[43] Michael G. Wohl and Robert S. Goodhart, eds., Modern Nutrition in Health and Disease: Dietotherapy , p. 10, tables 1.6 and 1.7.

[44] Ruch and Patton, p. 1045, table 3.

Mexican Indians we can make some adjustments for body size, but the nutritional aspect remains a separate problem.

We select a few of the most accessible and at the same time representative figures. The activity data refer to moderately large, well-conditioned North Americans or Europeans. The basis of at least some estimates is a 70-kilo man who is approximately 170 centimeters tall (154 pounds and 5 feet 7 inches). Such an individual has a surface area of 1.8 square meters. His basal metabolism would be 40 × 1.8 × 24 = 1,728 kilocalories a day, or in a round figure 1,730. If we use the hourly rate, we have a basal value of 72 kilocalories.

We now present two simple lists. Each shows the extra energy expended, presumably by a 70-kilo man, in performing certain tasks. The values per square meter have been converted to those for the whole person by using the multiplication factor 1.8. The units shown are kilocalories per hour. The lists are modified from the sources indicated, the figures in parentheses representing a further modification to arrive at values for an average central Mexican Indian adult male.

Sherman also shows a balance sheet in which is set forth a hypothetical 24-hour day, divided into portions according to activity.^[47] The basal metabolism is included in these figures:

[45] Henry C. Sherman, Chemistry of Food and Nutrition , p. 189, table 23.

[46] Ruch and Patton, p. 1045, table 2.

[47] Sherman, p. 190.

The activity load of the pre-Conquest central Mexican Indians is difficult to estimate. Initially, however, there must be established a reduction factor. A group which averages small size is sure to expend less energy than one of large dimensions. While we may know the comparative sizes, we are not sure of the exact relationship between the two groups in energy expenditure. On the other hand, some sensible assumption is required, and the simplest is that of direct proportionality. Therefore, if the mean basal rates in the two populations are in the proportion of 1,780 to 1,425, the values for the activity levels given above should be reduced to 82.4 percent. In the lists, the values thus adjusted for the central Mexican Indians are placed in parentheses. For example, the kilocalories used per day are reduced from 3,380 to 2,785.

The labor schedule of the overwhelming majority of pre-Conquest Mexican Indians was based upon farming, an activity conducted without aid from domesticated animals, by means of the digging stick as the principal implement. The work must be regarded as moderate, although numerous individual tasks were performed which might be classed as heavy. Relatively little work was done as strenuous as our really intensive manual labor displayed in both agriculture and industry. The women, of course, assumed all domestic duties, and their level of labor would have resembled what Ruch and Patton had in mind when they mentioned housework. Labor at home and in public service for the men, associated with occupations such as farming or building, would have been more onerous, but hardly could have surpassed the demands of steady bicycling for an equal amount of time. If so, the extra energy cost above the basal level would not have exceeded 155–160 kilocalories per hour. The same approximate value can be put on the energy cost of carrying loads, both domestically and over long distances, for the human cargador performed the function of the beast of burden used in the Old World. These cargadores carried a load of 50 pounds

each and traveled approximately one league an hour, or 2.5 to 3.0 miles depending upon the terrain. This activity, disregarding the loads, corresponds quite closely to Sherman's slow walk, which consumes an extra 106 kilocalories an hour. With the load, the value would certainly rise to 155–160 kilocalories.

Thus we formulate a workload estimate of 155–160 kilocalories per hour per man (for the sake of convenience, we shall use the value 156.7), and 70 kilocalories per day per woman. For children the value would be much smaller, but even the youngest children did a little work beyond their normal activity in helping their parents support the domestic establishment. On the other hand, it is extremely difficult to segregate work from play, so that it is preferable to reconsider children after a discussion of some other matters.

Another factor of importance is the allocation and distribution of time. In the instance of cargadores, we have the explicit testimony of Bernal Diaz, reporting on the situation in 1519 before the Europeans had had a chance to alter it, that a day's march was five leagues, or five hours' travel under load.^[48] The workday for the bearers must have included the time needed to make and break camp and to mount and dismantle the loads, perhaps an additional hour in all. The working day, then, was six hours. This is just about what the present-day Mexican farmer puts in, if one counts sustained work. Indeed, the six-hour day is prevalent throughout Latin America. It is a response to dietary limitations and also an adaptation to the climate. The serious working day extends from 6:00 or 7:00 a.m. to 12:00 or 1:00 p.m., at which time the heat in the tropical areas becomes unbearable. In many instances, although not always, a little more work may be done in the late afternoon, but approaching darkness precludes any extended effort. The rest of the time is spent eating, sleeping, and relaxing. This regimen is of very ancient origin and conforms to the exigencies of the region.^[49]

Let us now reconstruct a hypothetical day for an Aztec

[48] See the explicit statements of Bernal Díaz del Castillo (I, pp. 146 and 177): " . . . indios de carga, que en aquellas partes llaman tamemes , que llevan dos arrobas de peso a cuestas y caminan con ellas cinco leguas." The league was one hour's walk, the distance traveled varying with the difficulty of the terrain.

[49] If one allows for coffee breaks, visits to the toilet, and other interruptions in sustained work, the regime may not be much different from that in industrialized societies.

macehual , farmer, or cargador. He gets about eight hours sleep at night and one hour at noon. He works reasonably hard for six hours. He divides the remaining nine hours such that he indulges in light exercise for three hours and sits quietly the other six hours. Alternately, we may say that during these nine hours he engages in light activity. In either case, we may allow him an average extra expenditure of 37 kilocalories per hour. Then his formula is as follows:

Further adjustments are in order, the chief one of which relates to the number of days annually during which a full workload was carried. Throughout the year a proportion of days would be devoted to rest from all types of labor possible; that they came in our frequency of one in seven (now two in seven) seems unlikely; rather, they undoubtedly came in a relation to the Mesoamerican calendar with its 20-day units. Further, the accounts of Sahagún and those of other writers, native and Spanish, make it clear that the pre-Conquest Mexican Indians enjoyed a great many religious celebrations and festivals throughout the year.^[50] Some of these were confined to the ruling classes, priests, and nobility, but the common people participated in many of them. Merely as an estimate, let us say that days of rest and days of celebration and festival for the peasants gave them about 75 work-free days. If the work is deleted from the schedule shown above for 75 days in the year, and light activity is substituted, the value 940 is changed to 222 for the 75 days. Hence on these days the energy output was 2,067 kilocalories instead of 2,785. The annual output was reduced from 2,785 × 365 = 1,016,525 kilocalories to 75 × 2,067 + 290 × 2,785 = 962,675 kilocalories per year. This is equivalent to 2,637 kilocalories per day, say 2,635.

Let us turn now to the women. We know that they assisted

[50] See Sahagún, I, pp. 93–281; Motolinía, Historia , pp. 35–71.

to a significant extent in the farm work in addition to their work in the home. The extent of this extra labor cannot be precisely ascertained. However, we know that it could not have equaled that of the men, because so much time had to be spent in housekeeping, child care, and other necessary duties. On the other hand, the amount of farm labor must have been appreciable. It will be a moderate supposition to allocate to the adult female two hours of the six hours of labor on 290 days of the year. In kilocalories, the female balance sheet for a working day therefore looks as follows, where the cost of all types of work and activity is taken as having the same values as for men:

If we allow the same 75 days of rest and fiesta as for the men, we get per year for a female adult 2,155 × 290 + 1,915 × 75 = 768,575 kilocalories. This means 2,106 kilocalories per day, say 2,105.

We may now revert to the problem of the children. These young individuals cannot be said to have undergone labor in the strict sense. They performed many tasks, some of them onerous, but on the whole their activity must be classed as light. On the other hand, particularly with very young children, the hours of sleep must have been extended. In order to take these variables into account to some degree, although strict accuracy is impossible, we shall consider that the children slept ten hours (including a siesta) and spent their waking hours in light activity.

The basal metabolism of a child at the median age of 6 years was estimated to be 870 kilocalories per day, or 36.3 per hour. The sleeping metabolism is roughly 10% below the basal, or close to 33 kilocalories per hour and 330 per day. The basal value for 14 hours of waking is 508 kilocalories, rounded off to 510. The cost of digestion, because of the smaller size, may be

reduced to 80 kilocalories. The extra energy cost for 14 hours light activity in a child may be considered as lying between one-half and three-quarters of the value for an adult, or approximately 25 kilocalories per hour. This is admittedly a very crude estimate, but in view of the great range in age and size must represent an approach to the actual value. Thus we add to the other items 14 × 25 kilocalories per day, or 350, making a total energy output of 1,270 kilocalories per day. Since childhood activities will continue on nearly the same level, regardless of social events, no deduction need be made for days of rest or fiesta.

We now have a general average of 2,635 kilocalories for men, 2,105 for women, and 1,270 for children. If we apply the same proportions of these three components in the population as previously (27.5, 27.5, and 45.0% respectively) the average energy production per person per day becomes 1,875 kilocalories, a value we round off to 1,900 kilocalories. This value takes into account body size, age, and physical activity. It also assumes a diet adequate to supply the necessary calories. It does not take into account protein, accessory substances, or other factors which may affect the energy yield of the food eaten. Perhaps the most important point for our discussion is that it does not take into account circumstances that might reduce the caloric allowance available to the population, which might live not at a level of adequate nutrition but rather at one of semistarvation. This matter of possible semistarvation requires further exploration in our discussion.

The data concerning metabolism we have discussed up to now are based upon contemporary European and American dietary standards. They assume, unless otherwise indicated, that what is today considered an adequate diet was available to all persons, including Mexican and South American inhabitants, and that both the basal and the activity rates were determined only by such factors as age and body size. There is room, and indeed evidence, for doubting that this assumption is valid and warranted.

The level of nutrition today among the various groups in the Mexican population, both urban and rural, is the subject of acrimonious comment by many medical authorities and sociologists. They contend that a large segment of the population

suffers from chronic undernutrition.^[51] If this is true at present, and there is considerable evidence for the view, then it has been true throughout the history of the region. Consequently, the estimates offered here for mean energy production are too high and do not correspond to a human aggregate which was underfed. At this point we are interested primarily in the effect of inadequate caloric intake upon the mean output. By inadequate, we have in mind any level between that which is agreed upon as appropriate to maintain a population at full working efficiency and that which produces severe, manifest clinical symptoms such as are associated with outright chronic starvation.

The classical study involving undernutrition in great masses of people was carried out by Alexis Ivanovsky in Russia and made available to the western world in 1923.^[52] Ivanovsky followed the condition of over 2,000 adults for three years during a rigorous famine, and found an average reduction in height of 4.7 centimeters in males and 3.5 centimeters in females. The weight diminished to a varying degree, but the range was approximately from 20 to 60% of the initial value. He also found that among those who were exposed to inanition for long periods, the loss in size took place in the first year. Thereafter there was relatively little change.

A more rigidly controlled experiment was that of Ancel Keys and his colleagues at the University of Minnesota in the late 1940's, after the experiences of the Second World War had stimulated interest in the matter.^[53] In the Minnesota studies, a rapid initial loss of weight was observed; it was followed by a slower reduction until equilibrium was reached. The basal metabolism of the subjects also fell to a new low level. The changes are described by Keys and Francisco Grande:

Equally important is the fact that, given time, the body weight tends to

[51] See, for example, Richmond K. Anderson et al., "A Study of the Nutritional Status and Food Habits of Otomí Indians in the Mezquital Valley of Mexico"; Mendizábal, "Evolución económica y social," Obras Completas , VI, tables on food consumption between pp. 192–193; Salvador Zubirán and Adolfo Chávez V., "Algunos datos sobre la situación nutricional en México"; Carlos Pérez Hidalgo et al., "Recopilación sobre el consumo de nutritivos en diferentes zonas de México"; Ana María Flores, La magnitud del hambre en México, passim , esp. pp. 9–25; and Whetten, Rural Mexico , pp. 304–316.

[52] Alexis Ivanovsky, "Physical Modifications of the Population of Russia Under Famine."

[53] Ancel Keys and his colleagues have given a full report in the two volumes of The Biology of Human Starvation .

reach a steady state and calorie expenditure tends to balance calorie intake, no matter what the level of the latter may be. When we changed the diet of young men from 3,500 to 1,500 Calories daily, the weight loss was rapid at first and decreased exponentially with time until calorie equilibrium was achieved with the body weight being 25% less than it had been.^[54]

A similar result had been obtained in the well-known experiment of Benedict, Miles, Roth, and Smith (1919). These investigators kept a squad of young men on a low-calorie diet, an average of 1,930 kilocalories per day per man, after they had become accustomed to a diet consisting of 3,000 kilocalories per day. During the last three days of the restricted ration, the average net kilocalories produced per day was 2,245 and there was marked reduction in both the basal rate and the rate during moderate exercise. The subjects, however, felt no ill effects and were able to perform their tasks with facility. Sherman described the state of all these subjects as follows:

When conditions are otherwise favorable, healthy young men can adjust themselves to lowered energy intakes through reduced body weight and lowered BMR so that they can get along with 1/3 less food calories and still feel and act normal.^[55]

It is thus generally conceded that the food intake can be diminished from the high level associated with what are considered adequate diets with no permanent ill effects. There will be reduced weight, even reduced height, and at the same time lowered energy costs for all phases of life. If the reduction of intake is not too severe, the individual goes into and remains in what has been called the compensated phase of undernutrition. No clinical changes are observed except those mentioned; the person can continue a quite normal daily life.^[56]

We suggest that such a condition was present in the population of central Mexico on the eve of the Conquest, the cause being a low caloric intake. Such testimony as has come down to us all points in this one direction. The Relaciones Geográficas in many instances emphasize the frugality of diet for commoners

[54] Ancel Keys and Francisco Grande, "Body Weight, Body Composition, and Calorie Status," in Wohl and Goodhart, p. 24.

[55] Sherman, Chemistry of Food and Nutrition , p. 195.

[56] In addition to works already cited, see Francisco Gomez Mont, "Under-nutrition," in Wohl and Goodhart, pp. 984–995, esp. p. 988.

before the coming of the Spaniards. In the report for Cuilapan, written by Fray Agustín de Salazar, the comment is especially striking:

El comer de ellos es grima y espanto porque con unas tortillas de maiz y poco de agi y otras cosillas se contentan . . .

(Their food is a matter of disgust and horror, for with a few maize tortillas, a little chile, and other trifles, they are satisfied . . . )^[57]

Fray Agustín de Salazar was writing about his own time in 1581, but the Indian diet he described was that of the pre-Conquest as well. In Cuilapan it had not changed, much less improved.

In the history of Gonzalo Fernández de Oviedo y Valdés, who was never himself in central Mexico but questioned Spaniards who had been, including men of Cortés' army, is a summary of early testimony. According to Oviedo, the Indians of New Spain were the poorest of the many peoples who up to his time had been encountered in the New World. Their diet for the most part was maize and vegetables flavored with chile. The quantity was little, as he explains carefully, "not because they would not eat more if they had the food," but because the upper classes carefully assessed harvests and left them the bare minimum to sustain life and work until the next harvest.^[58] Oviedo's description of poverty is corroborated by Motolinía, who spent many years in New Spain:

Estos Indios cuasi no tienen estorbo que les impida para ganar el cielo . . . porque su vida se contenta con muy poco, y tan poco, que apenas tienen con qué se vestir y alimentar. Su comida es muy paupérrima, y lo mismo es el vestido . . .

(These Indians have almost no hindrance that might keep them from earning entrance to Heaven . . . for in life they are satisfied with very little, so little that they scarcely have the wherewithal to clothe and feed themselves. They eat most poorly indeed and clothe themselves in equal poverty . . . )^[59]

The Anonymous Conqueror summed up the matter tersely and elegantly:

 . . . es gente que se mantiene con poco alimento. (They live on little food.)^[60]

[57] In Tlalocan , II, p. 25.

[58] Oviedo y Valdés, Historia general , IV, pp. 248–250. See also [Anonymous Conqueror], Relación , p. 50.

[59] Motolinía, Historia , p. 85.

[60] [Anonymous Conqueror], pp. 41 and 50.

There is no certainty, however, that the level of food intake fell much below the compensated phase of undernutrition, for, irrespective of areas of seriously deficient diet today, no one has adduced evidence to show widespread clinical manifestations of starvation among the natives before Cortés. If the farmers and laborers, who constituted the overwhelming bulk of the population, were just below or even definitely below the present-day standard of adequate nutrition, then the mean daily rate of energy production fell below the 1,900 kilocalories we have calculated above. How far cannot be determined with any exactness. Sherman's level of a one-third reduction, which would mean here a reduction to 1,265 kilocalories, seems extreme. We shall be safer if we estimate the level as lying between 1,400 and 1,800 kilocalories. Clearly the marginal diet of the commoners would support a considerable amount of physical effort, but distinctly less than that possible to the better-fed and larger European or American laborer of today. The subliminal energy intake could be compensated by reducing physical effort. That there was malnutrition as against undernutrition seems unlikely, because the wide diversity of foodstuffs that were eaten would supply needed elements. The requirement for protein and amino acids would be met largely from maize, beans, and other plant components in the diet. Any requirement for protein of animal origin would be small, on the order of perhaps 15 to 30 grams daily for an adult male, and was easily met by eating insects, grubs, snakes, amphibians, birds, small mammals, and indeed "any living thing."^[61]

Our discussion has now arrived at the point at which we may make some examination of the probable amount of maize

[61] Anthony A. Albanese and Louise A. Orto, "The Proteins and Amino Acids," in Wohl and Goodhart, pp. 95–155, esp. pp. 97, 108, and 113–116; National Academy of Sciences—National Research Council, Evaluation of Protein Nutrition, passim . Anderson et al., in their "Study of the Nutritional Status and Food Habits of Otomí Indians in the Mezquital Valley of Mexico," reach the conclusion that: "The region is arid and barren and, economically and culturally, one of the most depressed in the country. The inhabitants eat very few of the foods which are commonly considered as essential to a good nutrition pattern. Their consumption of meat, dairy products, fruits, and vegetables is exceedingly low. However, through the eating of tortillas, the drinking of pulque (the fermented unfiltered juice of the century plant), and the eating of every conceivably edible plant available, a fairly good diet is maintained." Guillermo Bonfil Batalla, in Diagnóstico sobre el hambre en Sudzal, Yucatán (pp. 133–135), indicates a daily consumption as typical not merely of Sudzal but also of "more than twenty communities all over the country" that would come to approximately 1,808 kilocalories daily, 1,466 coming from the ingestion of 419 grams of maize, approximately 1/2 liter.

consumed daily by an Indian peasant and of probable production in pre-Conquest central Mexico. Obviously anything we indicate here must be highly tentative. We have now indicated that the overwhelming majority of the Indians lived at a level of compensated undernutrition. Accordingly, our previously published estimate of probable daily consumption is too high. That estimate was based upon the allowance prescribed by the viceroy in 1555 for Indians conscripted for repair of the dikes of the lakes of the Valley of Mexico, and presumably reflected a customary ration. The allowance was one cuartillo of maize a day.^[62] At 48 cuartillos in a fanega of 100 Castilian pounds (of 460 grams each, as against our pound of 453.6 grams), one cuartillo would be 958 grams of maize with a caloric value of approximately 3,350 kilocalories.^[63] That is a generous ration, and when supplemented by other foodstuffs provided by the Indians themselves might reach a value of 3,800 or 4,000 kilocalories.

It is possible that the ration, even at that relatively early date after the Conquest, already corresponded to European ideas, which were more generous; but what evidence we have on European rations for men engaged in fairly strenuous physical activity would not come to so high a value.^[64] Since the maize would be ground to meal and baked into tortillas for consumption, a service performed by women, we are inclined to suggest that the ration was for a man and his wife. Divided between them, it would come to the caloric values that we have indicated as probable. We shall return to these questions later in this essay. For the moment it is enough to suggest that the more

[62] Borah and Cook, The Aboriginal Population of Central Mexico on the Eve of the Spanish Conquest , p. 90; but see the entire discussion, pp. 89–92.

[63] We calculate 100 grams of maize as having 350 kilocalories. The value is a rough average of those given for various kinds of maize in Mercedes Hernández et al., Valor nutritivo de los alimentos mexicanos; Tablas de uso práctico , p. 6, and Juan Roca and Roberto Llamas, "Régimen alimenticio de los habitantes de la región de Izúcar de Matamoros (Puebla)," p. 584. For the maize of the sixteenth century, Roca and Llamas are probably nearer the true value at 341.81 kilocalories, since Hernández et al. deal with foods already greatly affected by the improvements of the Green Revolution—but the range from 341.81 to 366 is not great.

[64] See the references in note 6; additionally, Cesáreo Fernández Duro, La armada invencible , I, pp. 248–320, esp. pp. 274–278; and Maria Cristina Silveira and Carlos Silveira, "A alimentação na 'Armada Invencível.'" The Silveiras base their calculations on a manuscript prepared by the Marqués de Santa Cruz, proposing supplies and rations for the Great Armada, the copy they consulted being in the Biblioteca Nacional, Lisbon. Fernández Duro publishes the manuscript.

normal allowance for an adult male commoner was closer to a range from one-third to one-half of a cuartillo of maize (319–479 grams), say from 1,120 to 1,676 kilocalories, the remainder of the day's consumption of foodstuffs and perhaps a far greater proportion of vitamins, proteins, and trace elements coming from fruits, nuts, frijoles, chile, pulque, small amounts of animal substance, etc. The amount of maize annually consumed by a peasant family might range from 10 to 20 fanegas, as suggested for the post-Conquest period in the Valley of Mexico by Charles Gibson.^[65] For a family of average size before the Conquest, the likelier range would be 10 to 15 fanegas except in unusually favorable circumstances. The maize would be supplemented by a remarkable range of other foodstuffs.

The productivity of the pre-Conquest agriculture that provided this food is also difficult to estimate, since we have merely two sets of clues at this time and they are not easily reconciled. One set lies in the determinations of yields by Spanish tribute assessors in arriving at amounts and value of grain for tribute requirements set in plantings. Since such determinations occurred in the decades immediately succeeding the Conquest, we may assume that they reflect conditions substantially unchanged from aboriginal conditions. On an average, the determinations show a yield of 6.47 fanegas of maize for a planting of 1,000 square brazas,^[66] or a harvest on the order of 1,060 kilograms of maize per hectare.^[67] That average, which includes crops from irrigated and unirrigated land and from elevations from coast to plateau, is distinctly higher than the reported averages of Mexican agriculture just before the advent of the Green Revolution. We cannot exclude the possibility, therefore, that tribute maize was grown on the best land available to each town and was not representative of other yields.

[65] Gibson, The Aztecs Under Spanish Rule , p. 311.

[66] Cook and Borah, The Indian Population of Central Mexico, 1531–1610 , p. 19.

[67] Conversion of fanegas to kilograms is simple, since 1 fanega equals 46 kilograms. The braza is calculated at 1.6718 meters, the value given by Spain, Real Academia Española, Diccionario de la lengua española , from which we have taken the value for fanega. Sixteenth-century maize at this weight converts to dry measure at .83 kilograms per liter. These yields, which would work out to 14–16 bushels per acre, fall easily within the normal ranges indicated by Charles Gibson (The Aztecs Under Spanish Rule , pp. 309–310) for the Valley of Mexico in colonial times.

Our second set of clues on the probable yields of pre-Conquest agriculture is, of course, Mexican experience as recorded just before the remarkable changes that began in the 1940's and 1950's. In the first agricultural census of 1930, recording the agricultural year 1929–30, the range of yield for the states of central Mexico is enormous, from 472 to 1,237 kilograms of maize per hectare, and the returns subject to all the suspicions hovering around a new kind of statistical inquiry and one dependent upon thousands of respondents. The average for the states within the sedentary area of central Mexico as it was in 1520 is 633 kilograms per hectare, as against a countrywide average of 522. The countrywide average is for ejidos alone, 585, and for the private sector alone, 512. Productive units of one hectare and under were not asked to report.^[68] Since one would normally expect the private sector to be more productive, we are inclined to suspect underreporting on a considerable scale. The 1940 agricultural census, reporting the 1939–40 agricultural year, has more favorable results: The area of central Mexico gave average maize yields of 679 kilograms per hectare, the returns being divided between productive units of more than 5 hectares, with an average of 665 kilograms, and those of 5 hectares and less, with an average of 699 kilograms per hectare.^[69] So the two censuses, whatever the defects in them, indicate yields of maize for central Mexico ranging from 630 to 700 kilograms per hectare.^[70]

[68] Mexico, Dirección General de Estadística, Primer censo agrícola-ganadero, 1930. Resumen general, cuadro VIIIA, pp. 70–73. We have omitted Nayarit, Jalisco, Guanajuato, and Querétaro in our reconstitution of what was central Mexico in the sixteenth century, since they were then either sparsely settled or under the control of nomadic Indians. The 1930 census returns show an even greater range than the overall state averages indicate, since the average for ejidos in Puebla is 412 kilograms of maize per hectare, as against 1,424 kilograms for the Federal District.

[69] Calculated from Mexico, Dirección General de Estadística, Segundo censo agrícola-ganadero, 1940. Resumen general, cuadros 2 and 4, pp. 54–186 and 201–242.

[70] See also the annual averages of yields of maize per hectare from 1925 to 1937 in Mexico, Secretaría de Agricultura y Fomento, Memoria , 1937–1938, I, pp. 302–303, which show considerable fluctuation. If one turns to the 1950 agricultural census, the average yield per hectare for all of Mexico, after deduction of the crop of hybrid maize, was 786 kilograms. Land sowed to hybrid maize yielded on average 1,621 kilograms per hectare, but in that year so little was so sown that the average yield of maize of all types for all of the country was 790 kilograms per hectare. (Mexico, Dirección General de Estadística, Censos agropecuarios. 1. Totales comparativos en 1930, 1940 y 1950. 2. Por entidades y distritos economico-agricolas en 1950 , p. 15.)

These returns may be low because of underreporting—but may be too low, further, for comparison with pre-Conquest agriculture, because of the havoc of four and a half centuries of erosion, continued cultivation of land without adequate preservation of fertility, and the adoption of the plow as against the digging stick. The plow gives higher yields per man-hour spent on agriculture, whereas the digging stick usually gives higher yields per unit of land.^[71] Accordingly, we come to a range of probability: yields of maize for aboriginal agriculture may have been somewhere from 700 to 1,200 kilograms per hectare. That range of yield would have maintained the population we have postulated at the levels of nutrition postulated through cultivation of from 10 to 15% of the land.

4

Let us turn now to the decades after the Spanish Conquest. That conquest deeply altered the forms and fabric of native life. One would suppose that it should have affected native production and consumption of food. The question is: In what respects, and how far, in the sixteenth and first half of the seventeenth century? The coming of the Europeans made available technology, plants, and animals previously unknown and capable of deeply altering Indian food production and diet. In addition, that coming unleashed other changes which were bound to have a profound effect upon native utilization of land and other resources. Among the new plants and crops introduced by the Europeans were grains, such as wheat, barley, oats; vegetables, such as lettuce, radishes, carrots, cabbage; fruits, such as apples, quinces, oranges, lemons, peaches, apricots; nuts, such as walnuts. Two fruits introduced by the Spaniards that have unusual interest were bananas, from Africa but strange to many Spaniards and so described by them as native to Mexico,^[72] and guavas,^[73] which came from the Antilles. A third European introduction of a non-European

[71] See the comment by Gibson, The Aztecs Under Spanish Rule , pp. 309–310, and Francisco Javier Clavijero, Historia antigua de México , II, pp. 248–249.

[72] For example, Relación de las minas de Sultepec, 5 March 1582, PNE , VII, p. 9; Pedro Martínez, Descripción de la villa de Pánuco , p. 4.

[73] As in the Relación de Macuilsúchil, 9 April 1580, and the Relación de Chinantla, 1 November 1579, both in PNE , IV, pp. 103 and 65 respectively. The Relación de Chinantla correctly identifies guavas as coming from Hispaniola.

plant was the peanut, also from the Antilles, but given a Nahuatl name, tlalcacahoatl , little cacao—whence the present Mexican name cacahuate . In the sixteenth century it was raised in the region of Cuernavaca.^[74] Among the new animals were almost the entire array of Old World domesticates, such as horses, donkeys, mules, cattle, sheep, swine, goats, chickens, and the stinging bee, with its greater production of honey. For food production, the most important items of technology were the pasturage and uses of livestock and the Roman plow.

Among the changes unleashed by the coming of the Europeans was the sharp decline of the native population, largely through the introduction of Old World diseases, which reduced the aboriginal numbers in central Mexico as of 1518 by approximately 97% in roughly a century; that is, by the 1620's the Indian population of central Mexico was about 750,000, 3% of what it had been in 1518. The drop varied with region and climate, being most catastrophic on the coasts and considerably less on the plateau.^[75] Other changes were the insertion of the Spaniards as the new upper class; the relentless replacement of the native cult by Christian observances and clergy, but with a large underpinning of Indian assistants; demands for new services and products upon the Indian population by the Spanish overlords; the occupation of land and preemption of sources of water by the Spaniards for their own uses and purposes; and the beginning of the opening of the north to agricultural settlement, as the Spaniards applied the better European military technology to the problem of subduing the Chichimecs and settling the fine agricultural land thus made available.

The interaction of these factors made a complex pattern. The sharp and prolonged decline in Indian population made it impossible to cultivate large tracts of land. We know that very extensive tracts became waste, and that in consequence the availability of food through hunting, fishing, and gathering became correspondingly greater. We may further surmise that the Indian peasants of a town, forced to restrict cultivation to a much smaller part of their previous milpas and fields, would choose the better land for continued cultivation. Accordingly, the yield for effort spent on cultivation would improve; i.e., per

[74] Hernández, Historia natural , I, p. 306.

[75] See chap. 1 in this volume, and Cook and Borah, The Indian Population of Central Mexico, 1531–1610 , pp. 46–56.

capita output would rise. With the large expanses of land returned to waste, the Spaniards could occupy substantial tracts without serious harm to the Indian population, except for desirable portions that the Indians might have wanted to retain but that the Spaniards wrested from them. A further source of pressure was control of water. Land and water nearest large centers of Spanish population, particularly Mexico City, would have been the most subject to Spanish seizure, despite native wish to continue occupation. The more serious countrywide problem was the spread of Old World livestock, which ranged freely over the waste and quickly became feral or nearly so. It was no respecter of legal lines, and preyed upon the Indians' milpas and gardens if they were accessible.^[76] Had Old World livestock not moved into the ecological niche thus created, one may raise the question whether native species, such as deer, would not have multiplied with about the same result in harassing the Indians. Presumably deer and other wild species could be killed freely if found, whereas livestock had attached to them a presumptive Spanish property right.

One may measure the spread of Old World plants, animals, and technology through the reporting in tribute schedules, chronicles, land grants, and the Relaciones Geográficas. Although the Spanish attempted to persuade or force the Indians to raise wheat through requirement as tribute or other devices, the Indians found that the cultivation of wheat and other Old World cereals meant use of the plow, which in turn meant in the first years hiring a Spaniard and his work team of draft animals. They also found that the yield was less than that of maize, approximately 80% that of maize for the seed sown, and 70% for the area sown. Accordingly, there was persistent and substantial resistance to wholesale adoption of wheat. In more arid regions, where it had an advantage over maize, it was indeed used widely by the Indians, as in the Teotlalpan and the Mixteca Alta. Elsewhere, as the numerous references in the Relaciones Geográficas make clear, wheat was raised only in small quantities by the Indians. In general, the Hispanic com-

[76] For abandonment of land, land appropriation by Spaniards, and the spread of livestock, see Simpson, Exploitation of Land in Central Mexico in the Sixteenth Century, passim . See also Gibson, The Aztecs Under Spanish Rule , pp. 257–299 and 405–408; and William B. Taylor, Landlord and Peasant in Colonial Oaxaca , pp. 67–257.

munity, demanding wheat bread through tradition and the prestige of the European, had to raise its own wheat, appropriating land and labor for the purpose.^[77] Barley with its poorer yields was even less favored, and oats competing for use as fodder with the far more easily available and cheaper maize leaves and stalks were ignored by the Indians. The items of widest adoption among Old World plants were the fruits and vegetables, which were planted on a small scale for home use throughout much of central Mexico, climate and soil being suitable. In the warmer climates of the lower altitudes, two Old World plants had manifest advantage and were widely adopted. Bananas, with their prolific yield and small need for care, provided a warm-country staple that filled a genuine need and had no clear competition from native plants. Sugarcane, yielding a sweetener previously supplied only by honey or thickened maguey syrup, also filled a niche more fully than any previously available item.^[78]

Of Old World animals, the adoptions by Indians in the sixteenth and early seventeenth century arose from their perception of usefulness and to a lesser extent pressure from the viceregal authorities and Spaniards. The animal most widely accepted was the chicken, which quickly spread throughout the country.^[79] The adoption of the other animals may be traced in part through Lesley Simpson's study of viceregal land grants and permissions to raise livestock. The exact identification of use is somewhat obscured by the Spanish division of livestock into ganado mayor and ganado menor . Although it is certain that most estancias de ganado menor raised sheep, the term covered swine and goats as well. The mammalian domesticate most rapidly accepted by the Indians was sheep. Their interest was more likely the supply of wool than meat, for wool pro-

[77] In addition to material in the Relaciones Geográficas, see Gibson, The Aztecs Under Spanish Rule , pp. 319–326; Cook and Borah, The Indian Population of Central Mexico, 1531–1610 , p. 19; Borah, New Spain's Century of Depression , pp. 31–41.

[78] In general, bananas seem to have been raised in almost every town with a suitable climate. Sugarcane was less widely diffused by the time of the Relaciones Geográficas, but still is mentioned sufficiently to indicate a considerable measure of adoption by the Indians.

[79] By the time of the Relaciones Geográficas, chickens were present in virtually every town reporting. A few years later, Father Alonso Ponce and his companions were offered chickens for their food at almost every Indian town they came to. (Relación breve y verdadera . . . , passim .)

vided a far better fiber for cold-country use than any previously available, and enabled the plateau towns to make up the deficit of cotton that collapse of the tribute system of the Triple Alliance must have meant. According to Lesley Simpson's study, the overwhelming majority of grants to Indians were for sheep. A small proportion of grants were for raising horses and mules, and almost none were for raising cattle. The few such grants to Indians were on the eastern slopes of the plateau and in the north. In contrast, the majority of grants to Spaniards were for raising cattle, which spread rapidly throughout the country but were not in Indian ownership.^[80] The extent to which swine and goats were adopted by the Indians is more difficult to trace. Certainly they were used to a far more limited extent. Except in marginal areas, goats have little advantage, if any, and the use of the pig as a scavenger may have developed somewhat slowly, since the chicken is a competitor. One other Old World animal was also adopted fairly widely by the Indians, namely, the Old World bee, with its superior production of honey.^[81]

It is clear that the Indians in central Mexico adopted the plants, animals, and technology that made sense to them, and resisted the imposition of those items that meant a more expensive use of land and labor. The Roman plow, which meant the use of draft animals and the abandonment or destruction of steeply sloping land, spread very slowly.^[82] Its advantage over the digging stick was dubious at best, and the crop most immediately linked to it, wheat, considerably less advantageous than maize in terms of food per unit of land. Moreover, preparation of wheat for consumption in the Spanish manner required grinding and processing in ways not easily available to an Indian

[80] Simpson, Exploitation of Land in Central Mexico, passim .

[81] Relaciones Geográficas, passim . Charles Gibson, Tlaxcala in the Sixteenth Century , pp. 150–154, indicates wide raising of pigs by Indians in Tlaxcala in the second half of the sixteenth century, but that province may be aberrant, since the Relaciones Geográficas and Ponce's Relación breve y verdadera do not confirm such raising for all of central Mexico, nor does Gibson himself indicate it for the Valley of Mexico (The Aztecs Under Spanish Rule, passim) . See also Gómara's comment (II, p. 400): "Comen poca carne, creo que por tener poca, pues comen bien tocino y puerco fresco. No quieren carnero ni cabrón, porque les huele mal; cosa digna de notar, comiendo cuantas cosas hay vivas, y hasta sus mismos piojos. . . . "

[82] The spread of the plow among the Indians of central Mexico is clearly a story in itself that has never been explored. Clavijero (Historia antigua , II, pp. 248–249) indicates general adoption by the middle of the eighteenth century.

household. Equally slow was the spread of other crops dependent on the use of the plow. Chickens were an efficient scavenger, needing little care, able to fend for themselves, supplied eggs, and were a ready source of flesh in such small, inexpensive amounts that peasants could wring the neck of a chicken without reflecting upon the loss of revenue. Accordingly, they spread quickly. Sheep, with their special advantages in solving the needs of the Indians on the plateau, also spread quickly, although more slowly than chickens. The reasons for the slowness of the Indians to turn to raising cattle or pigs are less easily apparent. Cattle are more difficult to control than sheep, and perhaps more menace to milpas and gardens; they also represented a large investment without the annual yield of wool. Pigs may have looked less useful than chickens, a competing scavenger which both yielded eggs and came in smaller and more easily utilized units as flesh. On the other hand, pigs are the source of the highly prized cooking fat, lard, in a country which before the Spanish Conquest had no readily available, abundant supply of cooking fat or oil. Frying, one surmises, is essentially a post-Conquest culinary art. Finally, goats may have been considered less useful than sheep, yet in certain kinds of terrain their ability to browse on foliage instead of cropping grass allows them to survive where sheep cannot exist. Furthermore, goats are a good source of meat, and a rapid rate of reproduction is coupled with ready marketability.

Accordingly, in central Mexico, with the exception of a few of the more arid areas, Indian agriculture continued to raise maize, beans, squash, chile, tomatoes, as in the past, and the Indian diet continued to rely upon maize as a staple. What, then, did the Conquest bring in the way of change during the sixteenth and early seventeenth centuries?

First, the catastrophic shrinkage of the Indian population almost certainly meant that the survivors concentrated their efforts upon the better lands, and that average yields rose to correspond. So per capita output must have risen, and with it per capita consumption. Our study of prices of labor and of certain tribute commodities like maize indicates that in the second half of the sixteenth century wages rose more rapidly than commodity prices; that is, whatever the quirks of seasons, over the long term the wage of a day laborer tended to buy more maize. The main reason lay in the growing shortage of

labor,^[83] but the phenomenon is consonant as well with an improvement in per capita production and consumption.

A second change in food economy for which the Spanish Conquest was responsible was the pressure toward restriction of variety. It was economically more profitable under the European system to concentrate serious labor in the production of a few staple items, rather than to scatter energy in hunting and gathering types of food which were of diverse character and in the aggregate amounted to a great deal, but individually were trivial. Here would be found the snakes, insects, and algae. This reduction of multifarious natural sources occurred in the face of the introduction of new plants and animals, new grains, fruits, and vegetables. The latter species could be planted, harvested, and eaten under the supervision of the farmer, whereas the ancient resources flourished independently of any human control. Hence an apparent increase in resource range was actually accomplished by a canalization of effort which was more economical of effort than the old system and which actually furnished more edible material.

The further meaning of Old World animals for Indian food production and diet is distinctly more difficult to analyze. The Indian peasantry found a source of eggs and flesh in its chickens; in the end, the sheep and goats it raised would have made meat available, at least from old animals past any other usefulness. Furthermore, although the Indians did not take to raising cattle in the period we deal with, there is much testimony to the effect that they bought cattle for slaughter or bought beef from the Spaniards. Such beef was probably an item for the upper classes, and for the peasantry only on infrequent holidays.^[84] Indeed, for the Indian upper classes the changes undoubtedly meant mere substitution, as in deference to European ideas they gave up consumption of human flesh and forewent protein from snakes and insects in favor of flesh from

[83] Borah and Cook, Price Trends , pp. 39–46.

[84] Gibson, The Aztecs Under Spanish Rule , pp. 346–347; Gibson, Tlaxcala , p. 153; Ponce, Relación breve y verdadera, passim ; and Relaciones Geográficas, passim . The reports of the secretaries of Father Ponce would indicate a rather high consumption of beef by the Indians, but the Relaciones Geográficas, although also testifying to wide consumption of beef, indicate that ability to buy it played an important role in limiting consumption. See the detailed report by Juan Bautista Ponce in the Relación de Texcoco (García Icazbalceta, Nueva colección , III, pp. 49 and 54–55).

domesticated animals. For the lower classes the improvement was undoubtedly considerably less, but in an austere diet counted proportionately for far more. This improvement, in fact, constitutes the third probable change in food and nutrition referable to the Spanish invasion.

Although evidence is fragmentary, there are several bits which point to an increase in the average intake of both protein and kilocalories among the laborers and peasants of central Mexico in the decades from the middle of the sixteenth century to the middle of the seventeenth century. Our own examination of the wages of common labor in terms of purchasing power of maize indicates a rise in real wages after the first shock of the Conquest, a rise likely to have as one of its first effects an increase in consumption of basic foodstuffs. What evidence we have of rations and allowances of food point in the same direction. In September 1532 Lic. Maldonado, oidor of the Audiencia of Mexico, set the daily ration to be supplied by the town of Zicapuzalco to a slave gang working in the mines of Tasco at one cuartillo of maize, that is 1/48 of a fanega of 100 Castilian pounds, or 958 grams.^[85] In November 1555, as we have already indicated, Viceroy Luis de Velasco proposed that the royal government furnish the Indian workmen to be drafted for repair of the dike system controlling the water levels in the lakes of Mexico, with a daily ration of one cuartillo of maize. He also proposed that the city of Mexico furnish meat for the workmen in a quantity that unfortunately cannot be determined, but must have envisaged an issue of several ounces daily or three times a week.^[86] As we have already indicated, these were probably family rations.

Charles Gibson has assembled other evidence. According to him, in 1618 the standard ration for laborers on the Desagüe of the Valley of Mexico was one almud of maize per week, or 1/12 of a fanega. This means 12,880 kilocalories per week, or 1,840 kilocalories per day. Presumably other food was available to

[85] Mexico, AGN, El Libro de las tasaciones , pp. 633–634. The slaves may have been given meat from another source. Presumably women made the tortillas and were fed from this ration without additional allowance.

[86] Mexico (City), Actas de cabildo  . . . , VI, pp. 192–193, session of 4 November 1555. The viceroy proposed that the city furnish 1,000 pesos de minas, which would buy meat for the 6,000 Indian workmen during a period of two months. Unfortunately we do not know the official price of beef at this time. If we estimate the ration at approximately 4 ounces daily, the price would have been 20 maravedís the arrelde of 4 pounds, a perhaps reasonable price for 1555, which was a year of scarcity. The city council, alleging poverty, refused to provide the meat.

supplement this allowance, so that the total caloric intake might have reached 2,200 or 2,300 kilocalories. Much later, in 1769, the standard ration for hacienda labor was, according to Gibson, 2 almudes of maize a week.^[87]

These rations are high as allowances for a single man, even at hard labor. The question is pertinent whether this food was not intended for a man's family as well as for himself. There can be little doubt that such was the case on haciendas, where families were domiciled for long periods. We may also postulate the presence of women ministering to husbands working on the Desagüe, since the maize would have to be ground and baked into tortillas each day for consumption. Gibson mentions the presence of women tortilla-makers with the Desagüe labor drafts.^[88]

The one instance where there is room for doubt concerns workers in the obrajes, who were usually kept confined. The ordinances for workers in obrajes, issued in 1579 by Viceroy Enríquez, set the daily ration at 2 Castilian pounds of tortillas, tamales, or bread, that is, approximately 920 grams of whichever was issued, to be given in three metals, and

 . . . a medio día se les de un pedazo de carne los días que se pudiere comer, y a la noche tres o cuatro chiles; y el día que no fuere de carne se les de un cajete de frijoles o habas, y a la noche los chiles. . . .

( . . . at noon let them be given a chunk of meat on days when meat may be eaten, and at night three or four chiles; on days of abstinence let them be given a pot of frijoles or lima beans, and at night the chiles. . . . )^[89]

We cannot be sure of the exact weight of a "chunk of meat," nor probably could the Spaniards of the time, but it must have meant at least 4 ounces of bone, fat, and muscle, a considerable nutritive addition to the 2 Castilian pounds of tortillas, tamales, or bread. The tortillas, tamales, or bread would have had a value of 2,100 to 2,200 kilocalories. The meat would have contributed at least 250 kilocalories, plus 20-odd grams of animal protein. The chiles, plus scraps which the persons might pick up

[87] Gibson, The Aztecs Under Spanish Rule , p. 311.

[88] Ibid .

[89] Viceroy Enríquez, Mexico City, 7 November 1579, in Mexico, AGN, Boletín , XI (1940), p. 16. The ration was set in terms of weight to replace previous requirements that an Indian worker in an obraje be furnished daily 18 tortillas or 14 tamales and three times a week meat, on other days and in Lent frijoles, chile, or lima beans. Obraje owners either paid no attention or provided tortillas and tamales of small size and weight. Habas would normally mean horse beans, but in Mexican conditions were more likely lima beans.

from time to time, might add another 100 kilocalories,^[90] so that the total daily intake would have reached 2,450–2,550 kilocalories. This is clearly a reasonably generous allowance for one person engaged in moderate activity, if the obraje owner actually furnished it.

To sum up, definitive answers are precluded by a lack of evidence; yet there is a strong presumption that the extremely low nutritional levels endured by the Indians of pre-Conquest central Mexico were mitigated significantly after the first shock of the Spanish Conquest, that is, in a process that began by the second half of the sixteenth century. This presumption finds further support in the fact that the daily march of bearers under full load, which was five leagues or hours of work in 1519,^[91] increased under the Spaniards to six.^[92] Perhaps the strongest support is in the testimony of the Relaciones Geográficas, which repeatedly stress the austerity of life before the coming of the Spaniards and the greater abundance and ease for the commoner once the Spaniards had imposed their rule. The respondents were trying to explain the shocking disappearance of the Indian population; but their testimony, on the whole, is firmly in favor of the idea that living conditions for commoners had improved.

The Spaniards undoubtedly undertook to secure as much native labor as possible as cheaply as possible. The fact that they allowed their workers far more food than the latter had been accustomed to in the aboriginal state is evidence first that the food was available at low cost. This condition, in turn, is referable to the economic and demographic changes induced by the Conquest itself, and discussed here in a prior context. The increase in ration is also probably due in considerable measure to the opinion of the Spaniards on what constituted an adequate allowance. It must be remembered that the Spaniards were thorough Europeans, and that 2 pounds of bread or the equivalent and 4 ounces of meat, supplemented by some oil or fat and vegetables, constituted a minimal adequate diet for a working man, consistent with current Christian thought. We doubt if they could conceive of steady labor being performed when supported by a diet similar to that endured by the Mexica and other Indians of central Mexico under aboriginal conditions.

[90] Hernández et al., Valor nutritivo , pp. 6–16.

[91] See note 48.

[92] See the evidence assembled in Borah and Cook, Price Trends , pp. 41–42.