Two views of corn

In the late 1980s two prominent scientists with opposing points of view on genetically modified food crops were coincidentally doing intensive language study at Cuernavaca’s Cemanahuac Educational Community.

Memory Elvin-Lewis, M.D., of St. Louis, Missouri, was preparing for a trip to Peru to collect samples of plants with medicinal properties found in the Amazon rain forest. She was the employ of a U.S. pharmaceutical company searching for patentable new drugs. (Dr. Elvin-Lewis is the conscientious physician who when baffled by the disease which killed one of her patients in 1969, froze some of his blood and tissue. Eighteen years later she made the grim discovery that her patient had been the earliest known U.S.-born victim of AIDS.)

Cary Fowler, Ph.D., had been lobbying the United Nations’ Food and Agricultural Organization in Rome. He argued that farmers in countries that have given the world important food crops are entitled to some type of compensation from companies that exploit the genes from those crops. He cited as examples that Peru and Bolivia had given the world potatoes, Kenya had given us coffee, and Mexico had given corn. The Mexican government supported Dr. Fowler’s position in his negotiations in Rome.

Dr. Fowler was born and raised in Memphis, Tennessee, just downriver from the home of Dr. Elvin-Lewis, but their positions were worlds apart. Emotions ran high at the school and talks were scheduled for them to present their points of view to the assembled students.

Little did those of us present at the debate realize we were witnessing the beginning of a worldwide controversy that pits the survival of small farmers against giant agro-economic interests.
Dr. Fowler went on to be a key player in establishing the Svalbard Global Seed Vault, a frozen bunker north of the Arctic Circle in Norway. It contains hundreds of thousands of varieties of seeds that represent the genetic diversity now present around the world. The bunker is a sort of insurance policy against an agricultural Armageddon.

Years before the seed bank in Norway was established, Dr. Abel Muñoz Orozco at Mexico’s Chapingo University sought funding for a similar project here in the tropics. A seed bank of this kind needs to keep seeds frozen but he wondered, “In the future – in a Third World country – when the freezer breaks down will there be funding or interest in repairing it?” To guarantee that there would always be a freezer he proposed the seed bank be located in a concrete structure set in one of Iztaccihuatl’s glaciers.

I met Dr. Muñoz in the 1990s when the genetically modified seed projects were barely getting under way. He estimated that in each of Mexico’s 30,000 valleys farmers had developed corn appropriate for their particular geography. They’d developed varieties for wet areas, dry areas, different elevations, different soil types, different times of the year.

In many cases it is Mexican peasant farmers who maintain today’s corn seed banks in their storage sheds by selecting their best corn from the harvest to be planted the following year.

“Large seed companies don’t have that foresight,” Dr. Muñoz said. “Whenever their variety of corn is affected by blight they send their scientists to Mexico to scour through the 30,000 valleys until they find a variety of corn that is immune to that disease and soon they’re selling a new variety of patented seed – always as part of a package accompanied by their own herbicide and insecticide. Of course, they do so without factoring in any compensation for the farmers who developed that variety.”

Earlier this month environmentalist Dr. Vandana Shiva from India spoke in Cuernavaca about the use of transgenic seeds, seeds that had their DNA altered in a laboratory. “In India within a decade transgenic seeds took control of our entire cottonseed sector. 95% of the cottonseeds in India are transgenic. Half the price of cottonseed sold in India goes to St. Louis (to Monsanto). The price has jumped 8,000% The new seeds have created new pests we’d never had. Farmers now use 13 times more pesticide.”

Currently Mexico is in the world spotlight. A Mexican judge issued a temporary restraining order last September prohibiting the planting of genetically modified seeds in Mexico. Judge Jaime Eduardo Verdugo of Mexico City cited the risk of imminent harm to the environment as the basis for his decision. This month a higher court judge, Jaime Manuel Marroquín, upheld Judge Verdugo’s decision.

The executive branch of the federal government is now appealing the judges’ decisions. Is it NAFTA that has changed the government’s stance since the 1980s? Meanwhile countries around the world are citing Judge Verdugo’s decision as they refuse to allow the import of genetically engineered corn from the U.S.

The debate to which I listened attentively at Cemanahuac is now on the world stage and the stakes are enormous.

Limestone in Mesoamerica – one of Mexico’s most versatile resources in still widely used today

On a trip to Todos Santos Cucumatan in Guatemala's highlands I witnessed a process that goes on all the time here in Mexico, but out of sight. I had stopped at a family-operated limestone quarry. I could see where blocks of limestone had been cut out of a thick deposit. But even more facinating were the fire pits where limestone was being subjected to intense heat in order to reduce it to powder.  I came home with a football-sized piece of fired-limestone which, for lack of a better place, I put on top of my filing cabinet.  I've watched it disintegrate into powder over the span of a couple of years.  It reminds me just how fundamental limestone has been in Mesoamerican life.

Limestone can be found throughout Mesoamerica. Mexico's mountain ranges and ridges are full of limestone. The Yucatan Peninsula is a limestone shelf. You'll know you're in an area where limestone is plentiful wherever you see a cement factory.  In fact limestone is the principal ingredient in Portland Cement, the most common type of cement used in modern construction.  In addition to being used as mortar, limestone is the basis of concrete, stucco, and grout.

It's a very soft stone when in the ground and easy to cut and shape with stone and wooden tools, which is all the ancient Mesoamericans had.  In fact it is so soft that ground water cuts through it easily, often producing interconnected caves. You can visit an extensive limestone cave system at the Grutas de Cacahuamilpa, a three-hour drive from Mexico City in the state of Guerrero. Similarly the Yucatan Peninsula is honeycombed with cave systems. Snorkelers love to explore them.

When limestone is put in direct sunlight it dries out and becomes a hard and long-lasting building material.  The longer it is out in the sun the harder it becomes. 

Architects in ancient Mesoamerica would place orders with the nearby quarry for limestone building blocks. The blocks of stone were usually the size and weight that one person could carry. Architects would request blocks that were smooth on one side for walls or floors, or smooth on two sides for steps or corners. Irregularly shaped blocks made up the solid fill of buildings.

Small pieces of limestone where heated in the kilns. The resulting fine white powder was mixed with water to become stucco. Add sand and gravel to the mix and it became similar to cement or concrete.

In areas of Mesoamerica where limestone is abundant whole buildings and pyramids were built of limestone building blocks held together with limestone cement. You’d never have seen the building blocks though. The outside surfaces were always covered with limestone stucco. They’d put powder from ground up minerals of different colors into the last layer of stucco to produce brightly colored walls. Unfortunately stucco is the least durable use of limestone and has worn off most ancient buildings.

A serious downside to dependence on limestone mortar and stucco is that it is greedy for firewood. Twelve times more wood than stone is needed to heat the fires to reduce the limestone gravel to powder. Many archeologists trace the demise of Teotihucan -- the world's largest city in 550 A.D. -- to the denuding of the forests around the city. With no forested cover on the mountains, the summer rainfall rushed down the mountainsides, untrapped by the natural aquifer inside the mountains. This in turn led to a lack of water for the city's population that may have reached 250,000. 

Powdered limestone was not just used in construction. It has also been a key ingredient in the Mesoamerican diet in the form of tortillas. Corn was the staple grain of ancient Mesoamerica's diet and continues to be so.  Unless it is first nixtamalized, corn eaten in quantity will lead to debilitating diseases caused by a niacin (vitamin B3) deficiency.  Nixtalamization involves soaking and cooking kernels of corn in water and powdered limestone. This process breaks down the hull and transforms the nutrients in the kernel making them accessible to the human body.  When eaten along with beans and chile our bodies can transform the mix into protein.

Ground nixtamal becomes the dough or "masa" from which a tortilla is made.  It's only ingredients are corn, limestone powder, and water.  It is patted into the shape of a tortilla and cooked on a comal.  An additional health benefit of limestone in tortillas is the calcium it adds to the Mesoamerican diet.     

I find it elegant how a plentiful natural resource such as limestone has been and remains an integral part of Mesoamerican life.  And not just as a construction material but also as an essential part of the traditional Mesoamerican diet. 

Where tortillas come from

Most Mexican children are well experienced at being sent out "al madado" -- to buy tortillas just before breakfast or lunch.   Mothers give their children a special cloth in which to wrap the tortillas and just the right change to pay for them. The children go to a neighborhood tortillería where a clanging apparatus spits out hot and aromatic tortillas.

I first came upon a tortilla-making machine as an adult. I wonder what it is like to grow up with them as a child sent off to buy tortillas every day.  At first glance these machines look like complicated, disjointed contraptions, but really they are a compact, well-designed assembly line process. I wouldn't be surprised if early childhood awe over the tortilla-making machine leads to the National University's high enrollment in its School of Engineering. 

The machines are ubiquitous throughout the country.  You'll find them in small towns and city neighborhoods as well as in the fanciest of supermarkets.   The machinery is powered by electricity but the cooking is done with gas heat. In most neighborhood tortillerías the machines seem like they are always on the verge of breakdown with their covers removed years ago and their insides visible. Bicycle chains can be seen making gears turn and the conveyor belt move.  Just like something out of a Dr. Seuss book, the machines start making tortillas in the back of the store and shape, cut, cook, and pile up the finished product right at the front counter in less than a minute.

The Celorio brand machine puts out tortillas single file.  The Verastegui brand, designed for busier tortillerías, puts out tortillas which are almost side by side on the conveyor belt. It would be more correct to refer to designs rather than brands since most tortilla machines weren't purchased from the manufacturer. It's cheaper to buy parts and assemble one yourself following one of the traditional designs.   Too bad for the Celorio and Verastegui families, but that's the way it is.

The tortilla wouldn’t be possible without the ancient Mesoamaricans' discovery of the process of nixtamalization (an English word of Nahauatl origin). Corn was the staple of ancient Mesoamerica's diet and continues to be so for a substantial portion of the Mexican population.  Unless it is first nixtamalized, corn eaten in quantity will lead to debilitating diseases caused by a niacin (vitamin B3) deficiency.  Nixtalamization involves soaking and cooking kernels of corn in water and powdered limestone. This process breaks down the hull and transforms the nutrients in the kernel making them accessible to the human body.  When eaten along with beans and chile our bodies can transform the mix into protein.

Ground nixtamal becomes the dough or "masa" from which a tortilla is made. It's only ingredients are corn, lime, and water. Watch for a small pick-up truck delivering masa to a neighborhood tortillería.  You’ll see 50-kilo-bundles wrapped in a large cloth, referred to as a "maleta" (a suitcase).

At the tortillería, the maleta is put in the hopper of the tortilla-making machines. The machine presses the masa flat, cuts it into circles, and drops it on a conveyor belt where the tortillas cook. The tortillas on the conveyor belt expand and seem like they will fill up with air and pop. But they settle down by the time they get to where the conveyor belt drops the tortilla into a shoot where it comes to a standstill right on top of the tortilla ahead of it.

Tortillas made by machine have a characteristic that all Mexican cooks know about--they have a front and a back. Cooks will take this into account when rolling a tortilla into a taco or enchilada. They will make sure the inside of the folded tortilla is the weaker side, the side that bulged. 

As tortilla connoisseur Eduardo "Edy" Corona explained to me, “the machine's comal heats them more on one side than on the other.  In the machine the tortilla doesn't get cooked as evenly on each side as a hand made tortilla does."

It was interesting that Edy used the word comal to refer to part of the machine in which a metal conveyor belt keeps the tortillas moving at all times.  Comal properly refers to the flat griddle on which tortillas are traditionally cooked. Tortillas "hechas a mano" (made by hand), be they patted out by hand or squeezed flat in a press, are carefully laid on a hot comal.  They may inflate but they do so on both sides as they are flipped.

Neighborhood tortillerias that advertise “100% nixtamal” are where you’ll find tortillas made with the original Mesoamerican recipe, without fillers or preservatives.  You’ll also see a wonderful form of just-in-time movements, where vendors take orders from customers, weigh the tortillas, and make change just before the pile that has emerged from the machine is about to keel over.  And you’ll see children with their brightly-colored cloths out on their “madado”.

The need for a calendar

April and May are the hottest months of the year in central Mexico. On its apparent trip north to the Tropic of Cancer, the sun is climbing higher and higher in the sky. On May 16th it will be directly over Teotihuacan, in the very center of the dome of the sky, and it will set exactly in front of the Pyramid of the Sun. It will continue traveling north until reaching the Tropic of Cancer on June 20th – longest day in the northern hemisphere – when it will turn around, start its trip south, and be directly over Teotihuacan on July 28 when the weather, during the rainy season, will be delightful.

That transition in weather from almost unbearably hot and dry to the wonderful rainy season may be the origin of Mesoamerica’s need for a calendar.

There are two principal schools of thought in Mesoamerican anthropology – the diffusionists, and that of the advocates of the autochthonous development of Mesoamerican cultures.

Diffusionists maintain that unlike in ancient Egypt there was no need for a precise and accurate calendar in ancient Mesoamerica. Egyptians living in the Sahara needed to know when the Nile was going to flood. If they didn’t have their seeds in the ground just before the flooding they wouldn’t have a harvest to get them through the next year. The calendar they developed spread across Mesopotamia, India, Southeast Asia and somehow jumped across the Pacific to be adapted by the Mesoamericans.

Strangely the most noted diffusionist was the same person who coined the word Mesoamerica and listed its cultural characteristics--German anthropologist Paul Kirchhoff.

Kirchhoff pointed out that Mesoamerica has a dependable rainy season beginning in late May or early June, lasting until corn’s harvest in September. No need for a calendar. Farmers could see and feel the change in weather and have their seeds in the ground in time for the first rains.

Mexican archeologist Alberto Ruz became a spokesperson for the defense of the autochthonous development of Mesoamerican cultural characteristics. Ruz pointed out that the combination of poor soil in the rain forest, slash and burn agriculture, and a short rainy season made it essential for Mesoamerican farmers – especially Maya farmers in the lowlands – to know exactly when the rains were going to begin.

Corn, the staple of the Mesoamerican diet, takes about 120 days to grow from planting until harvesting. With a four month rainy season there is no leeway – the seeds must be in the ground before the rains begin. Yet, if in the ground too early they will rot.

On first glance the rainforest seems amazingly lush and fertile. However the buttress-type roots on the large trees give away the fact that the soil’s nutrients are concentrated at the surface. Roots spread horizontally from the base of trees in search of nutrients. Dense foliage keeps most of the sunlight from ever reaching the ground and drying out the soil. Rain forests cycle their nutrients as if in a greenhouse. When the cycle is broken by farmers clearing fields, land in the Mayan central lowlands (northern Guatemala and on south into Honduras) can only be used efficiently for two years before being left fallow for seven to ten years.

The Yucatan Peninsula’s soil is even poorer. After using it for two years traditional farmers leave it fallow for fifteen to twenty years.

Every two years Maya slash-and-burn farmers cleared a new field. They would do so in October. The longer the cuttings were allowed to dry before being set on fire, the more land there would be on which to plant. However waiting until the rains began meant the fire would not burn well, leaving nowhere to plant.

Ruz suggests early Mayas watched the sun. When it was directly overhead at noon, it was time to burn the fields and plant the seeds. They went on from there to perfect their calendar, reaching the astonishing precision of it being one ten-thousandth of a day more exact than the Gregorian calendar we use – only two ten-thousandths of a day from modern astronomers’ calculation of the true length of a year.

Central Mexico lies at the same latitude as the great deserts of the world. If it were not such a narrow country it would also be a great desert. Its rainy season is the hurricane season. Mexico benefits from the Caribbean and Pacific summer storms. Although we read about the tremendous devastation hurricanes leave in their path as they enter Mexico, if it weren’t for those storms Mexico’s natural aquifers would not be replenished. The storms allow for central Mexico’s wonderful summer weather of clear mornings, cloudy afternoons, and a tropical downpour lasting forty-five minutes to an hour in the late afternoon.

I’ve often thought what a break-through it would be if the Tourism Secretariat would let it be known to our northern neighbors that summers are cool and delightful in central and southern Mexico.

HOLY THURSDAY PROCESSION

On another matter, Taxco’s Holy Thursday procession is a marvelous example of well-rehearsed theater. It was the topic of last year’s Charlie’s Digs an April 19th and is just as timely this year. I hope to see you there.