The potato (Solanum tuberosum) is a perennial plant of the Solanaceae, or nightshade, family, commonly grown for its starchy tuber. Potatoes are the world's most widely grown tuber crop, and the fourth largest food crop in terms of fresh produce — after rice, wheat, and maize ('corn'). The potato was domesticated in southern Peru and northern Bolivia and is important to the culture of the Andes, where farmers grow many different varieties that have a remarkable diversity of colors and shapes, with over 100 varieties sometimes being grown in a single valley. In pre-Colombian times they were also widely cultivated on Chiloé Island, in Chile. Potatoes spread from South America to Spain and from there to the rest of the world after European colonization in the late 1400s and early 1500s. They soon became an important field crop.