Does the modern world owe its very existence to the humble spud? A recent study by a pair of economists suggests that the introduction of the American potato to Europe and later Asia and Africa might have been one of the most significant events in the history of human development.
The importance of potatoes first hit home for co-author Nancy Qian during a trip to rural Rwanda, where she noticed something about her hosts' diet. "All they were eating were potatoes," she says. At the time, Qian, a Yale University professor, was looking into how Rwanda's population explosion had helped cause its ethnic conflict, and she remembered reading a paper on how Ireland's 18th-century population boom had been fueled by the introduction of the potato. (Of course, the infamous 19th-century potato famine later brought thousands of Irish immigrants to the United States.)
Qian, along with Harvard University's Nathan Nunn, decided to see how universal the connection was. Looking at population trends from 1700, when the potato was introduced to the Old World, to 1900, they estimated that 12 percent of the population growth and 47 percent of the urbanization during this period was directly potato-related. Moreover, regions that are more suitable for potato cultivation -- Europe and India -- tended to urbanize and develop much faster than places that aren't, such as sub-Saharan Africa.
What gives the spud its magical power? First, as Qian says, "If you needed to choose only one crop to survive on, the potato would be it." It contains every nutrient humans need except for vitamins A and D, meaning that a person could survive indefinitely on only potatoes, milk, and a bit of sunlight. Potatoes are also very hardy, and they provide much higher yields than crops like corn and wheat, allowing countries to devote less space to farmland and more to cities and factories.
This could be why leaders from Frederick the Great to Ban Ki-moon have recognized the potato's power and encouraged farmers to grow them. Although its effect on population growth is less pronounced today, the potato is still a potent weapon in the fight against malnutrition, which led the United Nations to declare 2008 the International Year of the Potato. And that's no small fry.