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Origin of Agriculture Introduction • Knowledge of time and place of origin is important – For taxonomists and plant breeders – Present day plants are much different than the wild varieties • Genetically and morphologically different • Several genes (characterisitcs) are selected – Loss of plants is loss of gene pools from which new traits can be retrieved Introduction • Humans turned non-agricultural to agricultural way of life. • Agriculture; horticulture and domestication • Study history by – Carbon dating – Fossils – Phytoliths Why farm? • Work by Lee and Devore – !King bushmen of Kalahari desert of southern Africa • • • • Selected plant for adequate diet 105 species were used Did not work hard Not due to mal-nutrition or poverty • Not revolution but evolution De Candolle (1883) • Pioneering work • Criteria for recognizing centers of origin – Places where a plant grows spontaneously in a wild state – Places where fragments of plants in old deposits and buildings (archeological and palaeobotanical) are found – Archives describing the adventures of travelers. – Philogical (naming) origin Vavilov (1927) • • • • • • • • • • Center located in 20-45 degrees latitude 6-8 centers China India Central Asia Near East Mediterranean Ethiopia Mesoamerica South America Zhukovsky (1968) • Megagene centers – – – – – – – – – – – China Indochina - Indochina Australia - New Zealand India Central Asia West Asia Mediterranean Africa Europe - Siberia Mexico & Central America N. America Centers of Origin • Primary center: Places where initial formation of species has taken place • Secondary centers: new species formed due to mutations and hybridization. Has wide variety of subspecies Harlan (1971 and 1992) • • • • Centers and non-centers: three each Recently related biomes to cultivation Tundra – no cultivation Tropical: Sugar cane, banana, orange, mango and cocoa. Root crops and coffee • Temperate: cheery, apple, pear, grapes walnut, millets and wheat • Mediterranean: maize, rice, sorghum, cassava, sweet potato, bean, peanut, yams • Sea coast: coconut, cabbage, cotton, beet Old World Centers • The near east: 9,000 – 14,000 years ago. Fertile crescent of Mesopotamia. Wheat, barley, peas and vetch • The far east: 7,000- 8,000 years ago. China, Thailand, India. Rice, millet, rape and hemp New World Centers • Eastern North America: Cherokee Sunflower and cranberries • Western North America: Pueblo Dwellers Trees and shrubs; pine nuts and pigweed • Mexico: Aztecs and Mayans; Corn and beans • South American: Inca; Potato and chocolate Agriculture to day • 3% of land is used for cultivation • US: 1.9 billion acres – 310million acres for crop – 650 million acres for animal • Four major crops: 80% Corn, wheat soy and hay • All fruits and vegetable – 7% land • Cotton – 4%