The potato was first domesticated by the Inca Indians in the Andes Mountains of Peru and Bolivia. They developed hundreds of varieties adapted to high altitudes. Spanish explorers introduced the potato to Europe in the 16th century, but it was initially met with suspicion as it was not mentioned in the Bible and was part of the nightshade family. It eventually became a vital crop because it produced more food per acre than grain and was easy to hide from foraging armies during wars. The potato is high in Vitamin C, which helped end scurvy in Europe. However, heavy reliance on a single variety led to the Irish Potato Famine in the 1840s when a blight struck. Today, the potato is the world's fourth-largest food crop.