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Cassava (Manihot esculenta), also called yuca, mogo, manioc, mandioca, and kamoteng kahoy, a woody shrub of the Euphorbiaceae (spurge family) native to South America, is extensively cultivated as an annual crop in tropical and subtropical regions for its edible starchy, tuberous root, a major source of carbohydrates. It differs from the similarly-spelled yucca, an unrelated fruit-bearing shrub in the Asparagaceae family. Cassava, when dried to a starchy, powdery (or pearly) extract is called tapioca, while its fermented, flaky version is named garri.
Cassava is the third-largest source of food carbohydrates in the tropics.^[1][2] Cassava is a major staple food in the developing world, providing a basic diet for around 500 million people.^[3] It is one of the most drought-tolerant crops, capable of growing on marginal soils. Nigeria is the world's largest producer of cassava.
Cassava root is a good source of carbohydrates, but a poor source of protein. A predominantly cassava root diet can cause protein-energy malnutrition.^[4]
Cassava is classified as sweet or bitter. Like other roots and tubers, Cassava contains anti-nutrition factors and toxins.^[5] It must be properly prepared before consumption. Improper preparation of cassava can leave enough residual cyanide to cause acute cyanide intoxication and goiters, and may even cause ataxia or partial paralysis.^[6] Nevertheless, farmers often prefer the bitter varieties because they deter pests, animals, and thieves.^[7] The more-toxic varieties of Cassava are a fall-back resource (a "food security crop") in times of famine in some places.^[8]

History

Yuca in Moche culture, 100 AD, Larco Museum Collection

Wild populations of M. esculenta subspecies flabellifolia, shown to be the progenitor of domesticated cassava, are centered in west-central Brazil, where it was likely first domesticated more than 10,000 years BP.^[10] By 6,600 BC, manioc pollen appears in the Gulf of Mexico lowlands, at the San Andrés archaeological site.^[11] The oldest direct evidence of cassava cultivation comes from a 1,400-year-old Maya site, Joya de Cerén, in El Salvador,^[12] but the species Manihot esculenta likely originated^{[citation needed]} further south in Brazil and Paraguay. With its high food potential, it had become a staple food of the native populations of northern South America, southern Mesoamerica, and the Caribbean by the time of the Spanish conquest, and its cultivation was continued by the colonial Portuguese and Spanish. Forms of the modern domesticated species can be found growing in the wild in the south of Brazil. While several Manihot species are wild, all varieties of M. esculenta are cultigens.
Cassava was a staple food for pre-Columbian peoples in the Americas and is often portrayed in indigenous art. The Moche people often depicted yuca in their ceramics.^[13]
Since being introduced by Portuguese traders from Brazil in the 16th century, maize and cassava have replaced traditional African crops as the continent's most important staple food crops.^[14] Cassava is sometimes described as the 'bread of the tropics'^[15] but should not to be confused with the tropical and equatorial bread tree (Encephalartos), the breadfruit (Artocarpus altilis) or the African breadfruit (Treculia africana).