1493: Uncovering the New World Columbus Created

by Charles C. Mann

  Not only did the Columbian Exchange carry the ultra-productive potato to Europe and North America, it also brought ultra-productive Andean potato-cultivation techniques, including the world’s first intensive fertilizer: Peruvian guano. Andean peoples had mined it for centuries from great excremental deposits seabirds left on coastal islands. Fertilizer ships crossed the Atlantic by the hundreds, brimming with guano—and, many researchers believe, a fungus-like organism that blighted potatoes, causing a famine in Ireland that by some measures was the worst in the historical record.

  Not long after, potatoes fell to the attack of another imported species, the Colorado potato beetle. Panicked farmers turned to the first inorganic pesticide: a widely available form of arsenic, sprayed with enthusiasm over the field. Competition to produce ever-more-effective arsenic compounds launched the modern pesticide industry—the third component of modern agribusiness. Brought together systematically in the 1950s and 1960s, improved crops, high-intensity fertilizers, and artificial pesticides created the Green Revolution, the explosion of agricultural productivity that transformed farms from Illinois to Indonesia—and set off a political argument about the food supply that grows more intense by the day.

  SEA OF GENES

  In 1853 an Alsatian sculptor named Andreas Friedrich erected a statue of Sir Francis Drake on a marble plinth in the center of Offenburg, a small city in southwest Germany. Friedrich portrayed Drake staring into the horizon in orthodox visionary fashion. His left hand rested on the hilt of his sword. His right gripped a potato. “Sir Francis Drake,” the base proclaimed,

  disseminator of the potato in Europe

  in the Year of Our Lord 1586.

  Millions of people

  who cultivate the earth

  bless his immortal memory.

  The statue was pulled down by the Nazis on November 9, 1938, a small portion of the violent frenzy known as Kristallnacht. Destroying the statue was a crime against art, not history: Drake almost certainly did not introduce the potato to Europe. Even if he had introduced it, though, the statue would be misguided. Credit for Solanum tuberosum surely belongs most to the Andean peoples who domesticated it.

  Geographically, the Andes were an unlikely place for the creation of a major staple food. The second-biggest mountain range on the planet, the chain of peaks forms an icy barrier on the Pacific Coast of South America that is 5,500 miles long and in many places more than 22,000 feet high. Active volcanoes are scattered along its length like molten jewels on a belt. Ecuador alone had seven eruptions in the last century; San José, on Chile’s western border, has gone off seven times since 1822. The volcanoes are linked by geologic faults, which push against each other isometrically, triggering earthquakes, floods, and landslides. Even when the land is seismically quiet the climate is active. Temperatures in the highlands can fluctuate from 75°F to below freezing in the space of a few hours—the air is too thin to hold the heat. Sudden hailstorms splinter windows and drive vehicles off the road. Famously, El Niño—the name itself is an Andean coinage—brings floods to the coast and drought to the high plains. El Niño episodes can last for years.

  The Offenburg memorial to Sir Francis Drake’s introduction of the potato was destroyed by the Nazis. (Photo credit 6.1)

  The main part of the range consists of three roughly parallel mountain chains separated by high tablelands known as the altiplano. The altiplano (average altitude: about twelve thousand feet) holds most of the region’s arable land; it’s as if Europe had to support itself by farming the Alps. The sheer eastern face of the Andes catches the warm, humid winds from the Amazon, and consequently is beset by rain; the western, ocean-facing side, shrouded by the “rain shadow” of the peaks, contains some of the earth’s driest lands. The altiplano between has a dry season and a wet season, with most of the rain coming between November and March. Left to its own devices, it would be covered by grasses in the classic plains pattern.

  From this unpromising terrain sprang, remarkably, one of the world’s great cultural traditions—one that by 1492 had reached, according to the University of Vermont geographer Daniel W. Gade, “a higher level of sophistication” than any of the world’s other mountain cultures. Even as Egyptian kingdoms built the pyramids, Andean societies were erecting their own monumental temples and ceremonial plazas. Contentious imperia jostled for power from Ecuador to northern Chile. Nasca, with its famous stone lines and depictions of animals; Chavín, with its grand temples at Chavín de Huántar; Wari, landscape engineers par excellence; Moche, renowned for ceramics depicting every aspect of life from war and work to sleeping and sex; Tiwanaku, the highest urban complex ever built (it was centered on Lake Titicaca, the highest navigable lake on the planet); Chimor, successor to Moche, with its sprawling capital of Chan Chan—the tally is enormous. Most famous today are the Inka, who seized much of the Andes in a violent flash, built great highways and cities splendid with gold, then fell to Spanish disease and Spanish soldiers.

  The history of the civilizations of the Middle East and Egypt is entwined with the development of wheat and barley; similarly, indigenous societies in Mexico and Central America were founded on maize. In Asia, China’s story is written on paper made from rice. The Andes were different. Cultures there were nourished not by cereal crops like these but by tuber and root crops, the potato most important.

  Archaeologists have turned up evidence of people eating potatoes thirteen thousand years ago in southern Chile—not the modern Solanum tuberosum, but a wild species, S. maglia, which still grows on the coast. Geneticists remain uncertain, though, of the exact pathway by which Andean cultures created the domestic potato. Because early Andean natives mainly grew their tubers from seed and apparently planted multiple species of Solanum in the same garden, they would have produced countless natural hybrids, some of which presumably gave rise to the modern potato. One often-cited analysis tried to nail down the process; after much study, its author declared that today’s potato was bred from four other species, two of which bore the label “unknown.” Timing, too, is unclear: archaeologists have established only that Andean peoples were eating wholly domesticated potatoes by 2000 B.C.

  Potatoes would not seem obvious candidates for domestication. Wild tubers are laced with solanine and tomatine, toxic compounds thought to defend the plants against attacks from dangerous organisms like fungi, bacteria, and human beings. Cooking often breaks down a plant’s chemical defenses—many beans, for example, are safe to eat only after being soaked and heated—but solanine and tomatine are unaffected by the pot and oven. Andean peoples apparently neutralized them by eating dirt: clay, to be precise. In the altiplano, guanacos and vicuñas (wild relatives of the llama) lick clay before eating poisonous plants. The toxins in the foliage stick—more technically, “adsorb”—to the fine clay particles. Bound to dirt, the harmful substances pass through the animals’ digestive system without affecting it. Mimicking this process, Indians apparently dunked wild potatoes in a “gravy” made of clay and water. Eventually they bred less lethal varieties, though some of the old, poisonous tubers still remain, favored for their resistance to frost. Bags of clay dust are still sold in mountain markets to accompany them on the table.

  Andean Indians ate potatoes boiled, baked, and mashed as people in Europe and North America do. But they also consumed them in forms still little known outside the highlands. Potatoes were boiled, peeled, chopped, and dried to make papas secas; fermented for months in stagnant water to create sticky, odoriferous toqosh; ground to pulp, soaked in a jug, and filtered to produce almidón de papa (potato starch). The most ubiquitous concoction was chuño, made by spreading potatoes outside to freeze on cold nights. As it expands, the ice inside potato cells ruptures cell walls. The potatoes are thawed by morning sun, then frozen again the next night. Repeated freeze-thaw cycles transform the spuds into soft, juicy blobs. Farmers squeeze out the water to produce chuño: stiff, Styrofoam-like nodules about two-thirds smaller and lighter than the original tubers. Long expo
sure to the sun turns them gray-black; cooked into a spicy Andean stew, they resemble gnocchi, the potato-flour dumplings favored in central Italy. Chuño can be kept for years without refrigeration, meaning that it can be stored as insurance against bad harvests. It was the food that sustained the conquering Inka armies.

  Then as now, farming the Andes was a struggle against geography. Because the terrain is steeply pitched, erosion is a constant threat. Almost half the population cultivates some land with a slope of more than twenty degrees. Every cut of the plow sends dirt clods tumbling downhill. Many of the best fields—those with the thickest soil—sit atop ancient landslides and hence are even more erosion prone than the norm. Problems are exacerbated by the tropical weather patterns: a dry season with too little water, a rainy season with too much. During the dry season, winds scour away the thin soil. Heavy rainfall in the wet season sheets down hills, washing away nutrients, and floods the valleys, drowning crops.

  To manage water and control erosion, Andean peoples built more than a million acres of agricultural terraces. Carved like stairsteps into the hills, the Spanish voyager Pedro Sarmiento de Gamboa marveled in 1572, were “terraces of 200 paces more or less, and 20 to 30 wide, faced with masonry, and filled with earth, much of it brought from a distance. We call them andenes” (platforms)—a term that may have given its name to the Andes. (Fifteenth-century Indians used more appropriate methods than those ordered by Mao in the twentieth century, and had much better results.)

  On the flatter, wetter land around Lake Titicaca indigenous societies built almost five hundred square miles of raised fields: rectangular hummocks of earth, each several yards wide and scores or even hundreds of yards long. Separating each platform from its neighbor was a trench as much as two feet deep that collected water. During the night the trench water retained heat. Meanwhile, the complex up-and-down topography and temperature variation of the surface created slight air turbulence that mixed the warmer air in the furrows and the colder air around the platforms, raising the temperature around the crops by as much as 4°F, a tremendous boon in a place where summer nights approach freezing.

  In many places raised fields were not possible and so Indians constructed smaller wacho or wachu (ridges), parallel crests of turned-up earth perhaps two feet wide, separated by shallow furrows of equal size. Because the Americas had no large domesticable animals—llamas are too small to pull a plow or carry human beings—farmers did all the work with hoes and foot plows, long wooden poles with short hafts and sharp stone, bronze, or copper tips and footrests above the tip. Making a line across the field, village men faced backward, lifting up their foot plows and jabbing them into the soil, then stamping on the footrest to gouge deeper. Step by backward step, they created ridges and furrows. Each man’s wife or sister faced him with a hoe or mallet, breaking up the clods into smaller pieces. Placed in holes atop the wacho were potato seeds or whole small tubers (each had to have at least one eye, from which the new potato would sprout). Sacred songs and chants paced the labor as the line of workers moved methodically down the field. Breaks were accompanied by mugs of chicha (maize beer) and handfuls of coca leaves to chew. When one field was done, villagers moved to the next, until everyone’s fields were ready—a tradition of collective work that is a hallmark of Andean societies.

  Using a foot plow, Andean Indians break up the ground in this drawing from about 1615 by Felipe Guaman Poma de Ayala, an indigenous noble. Women follow behind to sow seed potatoes. (Photo credit 6.2)

  Four or five months later, farmers swarmed into the fields, digging up the tubers and leveling the wacho for the next crop—often quinoa, the native Andean grain. Every scrap of the potato plant was consumed except the toxic fruits. The foliage fed llamas and alpacas; the stalks became cooking fuel. Some of the fuel was used on the spot. Immediately after harvest, families piled hard clods of soil into igloo-shaped ovens eighteen inches tall. Inside the oven went the stalks, as well as straw, brush, and scraps of wood (after the Spaniards came, people used cattle manure). Fire heated the earthen ovens until they turned white. Cooks pushed aside the ashes and placed freshly harvested potatoes inside for baking. Villagers in the heights still do this today—the stoves glow in the twilight, dotting the hills. Steam curls up from hot food into the clear, cold air. People dip their potatoes in coarse salt and edible clay. Night winds carry the bakery smell of roasting potatoes for what seems like miles.

  The potato roasted by precontact peoples was not the modern spud. Andean peoples cultivated different varieties at different altitude ranges. Most people in a village planted a few basic types, but everyone also planted others to have a variety of tastes, each in its little irregular patch of wacho, wild potatoes at the margins. The result was chaotic diversity. Potatoes in one village at one altitude could look wildly unlike those a few miles away in another village at another altitude.

  When farmers plant pieces of tuber, rather than seeds, the resultant sprouts are clones; in developed countries, entire landscapes are covered with potatoes that are almost genetically identical. By contrast, a Peruvian-American research team found that families in a mountain valley in central Peru grew an average of 10.6 traditional varieties—landraces, as they are called, each with its own name. Karl Zimmerer, now at Pennsylvania State University, visited fields in some villages with as many as twenty landraces. The International Potato Center in Peru has sampled and preserved more than 3,700. The range of potatoes in a single Andean field, Zimmerer observed, “exceeds the diversity of nine-tenths of the potato crop of the entire United States.” (Not all varieties grown are traditional. The farmers produce modern, Idaho-style breeds for the market, though they describe them as bland—they’re for yahoos in cities.)

  In consequence, the Andean potato is less a single identifiable species than a bubbling stew of many related genetic entities. Sorting it out has given decades of headaches to taxonomists (researchers who classify living creatures according to their presumed evolutionary relationships). Learned studies of cultivated potatoes in Andean fields have divided them, variously and contradictorily, into twenty-one, nine, seven, three, and one species, each further sliced into multiple subspecies, groups, varieties, and forms. Four is probably the most commonly used species number today, though the dispute is anything but resolved. As for S. tuberosum itself, the most widely accepted recent study parcels it into eight broad types, each with its own name.

  The potato’s wild relatives are no less confounding. In The Potato, a magnum opus from 1990, the potato geneticist J. G. Hawkes proclaimed the existence of some 229 named species of wild potato. That did not lay the matter to rest. After analyzing almost five thousand plants from across the Americas, Dutch researchers in 2008 winnowed Hawkes’s 229 species down to just ten fuzzily defined entities—“species groups,” as they put it—that bob like low, marshy islands in a morass of unclassifiable hybrids that extends from Central America down the Andes to the tip of South America and “cannot be structured or subdivided” into the classic species in biology textbooks. The description of the wild potato as a trackless genetic swamp was, the Dutch admitted, a view that their colleagues might find “difficult to accept.”

  Andean natives bred hundreds of different potato varieties, most of them still never seen outside South America. (Photo credit 6.3)

  None of this was apparent, of course, to the first Spaniards who ventured into the Andes—the band led by Francisco Pizarro, who landed in Ecuador in 1532 and attacked the Inka. The conquistadors noticed Indians eating these round objects and despite their suspicion sometimes emulated them. News of the new food spread rapidly. Within three decades, Spanish farmers as far away as the Canary Islands were growing potatoes in quantities enough to export to France and the Netherlands (then part of the Spanish empire). The first scientific description of the potato appeared in 1596, courtesy of the Swiss naturalist Gaspard Bauhin, who awarded it the name of Solanum tuberosum esculentum, which later became the modern Solanum tuberosum.

 
Folklore credits Francis Drake with stealing potatoes from the Spanish empire during a bout of piracy/privateering. Supposedly he gave them to Walter Ralegh, founder of the luckless Roanoke colonies.2 (Drake rescued the survivors.) Ralegh asked a gardener on his Irish estate to plant them. His cook is said to have served the toxic berries at dinner. Ralegh ordered the plants yanked from his garden. Hungry Irish picked them up from the refuse—hence, apparently, the statue of Drake in Germany. On its face, the tale is unlikely; even if Drake snatched a few potatoes while marauding in the Caribbean, they would not have survived months at sea.

  The first food Europeans grew from tubers, rather than seed, the potato was regarded with fascinated suspicion; some believed it to be an aphrodisiac, others a cause of fever, leprosy, and scrofula. Ultraconservative Russian Orthodox priests denounced it as an incarnation of evil, using as proof the undeniable fact that potatoes are not mentioned in the Bible. Countering this, the pro-potato English alchemist William Salmon claimed in 1710 that the tubers “nourish the whole Body, restore in Consumptions [cure tuberculosis], and provoke Lust.” The philosopher-critic Denis Diderot took a middle stance in his groundbreaking Encyclopedia (1751–65), Europe’s first general compendium of Enlightenment thought. “No matter how you prepare it, the root is tasteless and starchy,” he wrote. “It cannot be regarded as an enjoyable food, but it provides abundant, reasonably healthy food for men who want nothing but sustenance.” Diderot viewed the potato as “windy” (it caused gas). Still, he gave it the thumbs-up. “What,” he asked, “is windiness to the strong bodies of peasants and laborers?”

  With such halfhearted endorsements, it is little wonder that the potato spread slowly outside of the Spanish colonies. When Prussia was hit by famine in 1744, King Frederick the Great, a potato proponent, had to order the peasantry to eat potatoes. In England, farmers denounced S. tuberosum as an advance scout for hated Roman Catholicism. “No Potatoes, No Popery!” was an election slogan in 1765. As late as 1862, the British cookbook and household advice writer Isabella Beeton was warning her readers not to drink “the water in which potatoes are boiled.” France was especially slow to adopt the new crop. Into the fray stepped nutritionist, vaccination advocate, and potato proselytizer Antoine-Augustin Parmentier, the Johnny Appleseed of S. tuberosum.