Publications /  The Potato, Treasure of the Andes
From Agriculture to Culture

Let us go on an imaginary expedition, from the gray-green shores of the Pacific Ocean to the steamy Amazon jungle. We are about to travel to the home of one of nature’s most generous gifts, the potato, that modest yet sublime food. Our journey will bring us face-to-face with the Andes, a giant that, even in today’s cybernetic times, remains the guardian of millions of people. The history of the Andes is one of action and reaction, of conflict and adaptation. Life in these mountains has never been easy. Climate, topography and altitude – each has made severe demands on the life forms that have taken root here. These age-old struggles gave rise to some of the most advanced cultures in human history, and some of the world's most versatile plants and animals. The Andes rose in the Cretaceous Period, when the Earth's crust along the Nasca plate launched the opening salvos in an ongoing battle with the South American plate. This tectonic conflict sparked violent volcanic eruptions and earthquakes that, over the course of more than 28 million years, forced enormous masses of sedimentary rock to rise up along the western edge of the South American continent. The result was one of the highest and most spectacular mountain ranges on Earth.

The Andes run north-south for 7,240 km, from Panama to Cape Horn, with an average width of 240 km and an average altitude of 3,660 m. Among the peaks are the two highest mountains in the Americas: Mount Aconcagua, on the border between Argentina and Chile, rising to 6,959 m, and Mount Huascarán, in Peru's Cordillera Blanca massif, which looms at 6,768 m. Mount Huascarán is just 80 km from the Pacific coast. Its lofty altitudes, considerable length and north-south orientation have endowed the range with an enormous variety of climates. Myriad local differences – in soil, slope, humidity and precipitation, among others – have created a host of microclimates. This climatic complexity is one of the main reasons why the Andes are such a great source of biological diversity – a modern-day Noah's Ark.

EASTWARD AND UPWARD

Our journey begins on the Pacific coast, where the foothills of the Andes climb from the Atacama Desert in northern Chile and the Sechura Desert in northern Peru. These are vast sand bowls swept by the wind and split at intervals by fertile valleys. These oases are home to the algarrobo and huarango trees, whose products have served humanity for millennia; to the white-tailed deer and the coastal fox, mythological symbols of purity and cunning; and to sweet potatoes, beans and squash, crops that anchored the economies of countless pre-Hispanic peoples. In some places, the mountains rise directly from the sea, forming dizzying cliffs washed constantly by the waves. Elsewhere, the peaks are set back behind coastal plains known as pampas or hilly zones called lomas. The lomas are worlds where mist and dew condense in winter, giving life to a unique set of animals and plants, among them the chamico, amancae and wild tobacco.

Continuing eastward, we leave the hills and dunes behind and climb into an arid and rocky mountainous area. These are the yungas, a land of valleys, gorges, canyons and mountains rising as high as 2,300 m. The term yungas comes either from the Quechua yunca, meaning warm valley, or from the Aimara yunga, meaning sterile or barren. Under the clear skies of the yungas, the sun beats down on the bare land for more than 3,000 hours a year. With seasonal rains providing the only moisture, survival is a struggle. Here, one can both breathe the salty sea breeze and feel the chilly winds that sweep down from the highlands. The rocky soil is broken by cacti and twisted molle trees (known as cuyash or “beloved ones” because of their many uses), by magueys and by a variety of fruit-bearing trees, such as avocado, chirimoya and lúcuma. The people of the yungas made phenomenal efforts to overcome the scarcity of fertile land. The most impressive of these endeavors are the complex and efficient agricultural terracing and irrigation systems.

Moving eastward and upward, we reach narrow passes that serve as gateways to new ranges of hills and mountains. Between 2,300 and 3,500 m, rivers that thunder down from the heights have carved out deep valleys. Home of the ancient pisonay, this territory is known as the quechua, or the land of the benign climate. But this benign quality is relative. In the quechua, the differences between day and night temperatures and between sunshine and shade are extreme. This is the lower limit of the much-feared winter frost. It is a region of electric storms and torrential rains, believed by the ancients to symbolize battles in an eternal war between two mythological beings – one from the sea and the other from the mountains – whose fights were marked by roars and bolts of fire.

Yet this land has been a surprisingly hospitable host for living beings. The best known among the quechua's tenants is the potato, in its thousands of varieties. But here one can also find maize (called sara or anca in ancient times); the alder (a tree that provides dyes, wood for construction and medicine); and food plants such as aguaymanto, amaranth, arracacha, caigua, capulí, tarwi and yacón. Human beings have lived in harmony and worked this land for thousands of years, building and maintaining irrigation canals to ensure a steady flow of water. Climbing farther we reach the puna, or high plain, between 4,000 and 4,800 m, home to the vicuña and the condor. This region, swept by eternal winds, features winding rivers, rolling plains covered in ichu grass and studded with tola trees, and lakes fringed by totora reeds.

The puna seems a hostile place (its very name means dizziness, altitude sickness). Yet if we look closely, we can see that life thrives here. This is the ideal habitat for nutritious crops such as kañiwa, mashua, oca and quinoa. Herders tend their alpacas among bright green marshes teeming with ducks, coots and flamingos. The highland plain is home to the energy-giving maca root and to a vast array of native potatoes (many of which contain chemicals that protect them from blight and frost). It is also a haven for the wild cuy, the Andean wildcat, the fox and the taruca, the largest deer in the Andes. Brightly colored cantuta bushes, gnarled kiswar trees, flowering cacti and pretty chinchircumas lend touches of fragile beauty to the landscape. The canyons of the puna shelter some of the world's highest forests, the last stands of qolle and qiwña. For centuries, these trees have provided the people of the region with firewood and tender shoots for cattle forage. The forests also serve as water reservoirs and sanctuaries for unusual animals that thrive in a world of twisted branches, tiny leaves and ochre-colored shoots. Two plants, one monumental, the other delicate and subtle, demonstrate the extremes to which living things have gone to adapt to this land marked by sharp contrasts and scarcity. The majestic Puya raimondii grows for a hundred years before it finally explodes into bloom, and then dies. The tiny yareta, on the other hand, clings to cold highland boulders, sheltered from the fierce wind. It grows over the course of decades, but at the sluggish pace of a centimeter a year.

THE SOURCE OF THE AMAZON

Above the puna rises a land of glaciers – the janca, the roof of the Americas – at an altitude of more than 4,800 m. From here, with our backs to the Pacific, we gaze out on a layer of cloud, rolling toward us in endless waves from the tropical Amazon basin. The eastern slopes of the Andes present a stark contrast to the western slopes facing the Pacific. Dense forests bathed by frequent rains cover this landscape. Torrents and waterfalls flow through woodlands where human beings have rarely ventured. It is a land riddled with narrow valleys and spectacular gorges. In its upper reaches, shrouded by chilling fogs, mysterious dwarf forests grow. These are kingdoms of moss and lichen, where nature appears to have inverted the size of species: beetles the size of birds and deer that stand barely 20 cm tall.

Journeying eastward, we descend to the mild climate of the middle altitudes. Here plants grow in a huge variety of shapes and colors, such as giant begonias and ferns the size of trees; orchids with bizarre shapes and delicate bell-shaped flowers that attract swarms of bees, beetles and hummingbirds; heliconias that look like wax figures and mallows like masks for some Andean festival. If we are lucky, we may also spot the cock-of-the-rock, the elusive spectacled bear, the yellow-tailed woolly monkey, the torrent duck or some of the dozens of species of fruit-eating birds whose brightly colored plumage competes for our attention with the flowers of the forest.

As we continue eastward, a magnificent landscape unfolds at our feet. The last of the foothills disappears into the jungle foliage and before us stretches a vast tropical plain nourished by one of the world's largest river systems. These sluggish waters rose in clear Andean streams; they have made their way to the lowlands, bringing with them the sediment of the highland gorges to nourish a host of creatures.

Our journey across the Andes is complete. Behind us rises a jagged spine of peaks, a forbidding wall of rock and ice that seems to challenge the very notion of survival. But as we turn again to look out across the teeming Amazon forest, we know that this is not the case. Our excursion has helped us to understand the incredible diversity of the land that has produced and nurtured the potato, and so many other living things. The Andes, despite their apparent harshness, are a veritable fountainhead of life.