Origin Maize

maize domesticated variant of teosinte. 2 plants have dissimilar appearance, maize having single tall stalk multiple leaves , teosinte being short, bushy plant. difference between 2 largely controlled differences in 2 genes.

several theories had been proposed specific origin of maize in mesoamerica:

in late 1930s, paul mangelsdorf suggested domesticated maize result of hybridization event between unknown wild maize , species of tripsacum, related genus. theory origin of maize has been refuted modern genetic testing, refutes mangelsdorf s model , fourth listed above.

the teosinte origin theory proposed russian botanist nikolai ivanovich vavilov in 1931 , later american nobel prize-winner george beadle in 1932. supported experimentally , recent studies of plants genomes. teosinte , maize able cross-breed , produce fertile offspring. number of questions remain concerning species, among them:

the domestication of maize of particular interest researchers—archaeologists, geneticists, ethnobotanists, geographers, etc. process thought have started 7,500 12,000 years ago. research 1950s 1970s focused on hypothesis maize domestication occurred in highlands between states of oaxaca , jalisco, because oldest archaeological remains of maize known @ time found there.

connection parviglumis subspecies

teosinte (top), maize-teosinte hybrid (middle), maize (bottom)

genetic studies led john doebley identified zea mays ssp. parviglumis, native balsas river valley in mexico s southwestern highlands, , known balsas teosinte, being crop wild relative teosinte genetically similar modern maize. has been confirmed further more recent studies, refined hypothesis somewhat. archaeobotanical studies published in 2009 point middle part of balsas river valley more location of domestication; river not long, these locations not distant. stone milling tools maize residue have been found in 8,700-years old layer of deposits in cave not far iguala, guerrero.

also, doebley part of team credited first finding, in 2002, maize had been domesticated once, 9000 years ago, , spread throughout americas.

a primitive corn being grown in southern mexico, central america, , northern south america 7,000 years ago. archaeological remains of maize ears, found @ guila naquitz cave in oaxaca valley, date 6,250 years; oldest ears caves near tehuacan, puebla, date ca. 3,450 bc.

maize pollen dated 7300 cal b.p. san andres, tabasco, on caribbean coast has been recovered.

as maize introduced new cultures, new uses developed , new varieties selected better serve in preparations. maize staple food, or major staple – along squash, andean region potato, quinoa, beans, , amaranth – of pre-columbian north american, mesoamerican, south american, , caribbean cultures. mesoamerican civilization, in particular, interrelated maize. traditions , rituals involved aspects of maize cultivation – planting food preparation. maize formed mesoamerican people s identity.

stucco head of maya maize god, 550-850 ad.

it unknown precipitated domestication, because edible portion of wild variety small , hard obtain eaten directly, each kernel enclosed in hard bivalve shell. possible that, on, teosinte may have been gathered preferred feed domestic animals.

also, in 1939, george beadle demonstrated kernels of teosinte readily popped human consumption, modern popcorn. have argued have taken many generations of selective breeding produce large, compressed ears efficient cultivation. however, studies of hybrids readily made intercrossing teosinte , modern maize suggest objection not founded.

spreading north

around 2500 bc, maize began spread north; first cultivated in united states @ several sites in new mexico , arizona, 2100 bc.

during first millennium ad, maize cultivation spread more in areas north. in particular, large-scale adoption of maize agriculture , consumption in eastern north america took place a.d. 900. native americans cleared large forest , grassland areas new crop.

in 2005, research usda forest service suggested rise in maize cultivation 500 1,000 years ago in southeastern united states corresponded decline of freshwater mussels, sensitive environmental changes.