Mexican people planted corn 10,000 years ago

The ancestor of the original corn plant grows wild in completely different Mexico, the modern plant is the most important food source in the world. While the evidence clearly indicates that maize was first grown in Mexico, the earliest planting time and place as well as the spread of maize are still controversial.

Currently in addition to traditional archaeological and macro botanical sites, scientists are using micro-botanical techniques and new genetic techniques to distinguish corn grown as a crop from wild ancestors. as well as to identify ancient corn cultivation sites. New analysis shows that Mexicans may have grown corn 10,000 years ago.

Dr. John Jones and his colleagues Mary Pohl and Kevin Pope have reviewed many different evidence, including remaining paleontological evidence such as pollen, phytoliths (non-degradable inorganic substances according to time), starch grains as well as genetic analyzes to reconstruct the history of early corn cultivation. Dr. Jones, of the Department of Anthropology, Washington State University - Pullman will present his research at the Corn Tree Symposium at the annual meeting of the American Society of Plant Biologists in Mérida, Mexico. (June 28, 2008).

While the remaining macro-botanical evidence such as corn kernels, corn cobs and corn leaves are found in dry mountain caves, they are not preserved in the wetter lower regions. Consequently, the conclusions based on the above evidence are sporadic. Many small parts of corn plants such as intracellular silicon dioxide called phytoliths, pollen and starch grains are preserved in both wet and dry conditions. These evidence, along with genetic and archaeological data, are being used to reconstruct the history of farming to the origin of corn plants worldwide.

Corn in Latin America has a variety of shapes and colors.(Photo: Keith Weller / USDA / Agricultural research industry)

Corn is a pollinated plant by the wind, dispersing a lot of pollen on soil and water. The hard outer layer of pollen protects it from damage, even though thousands of years have passed. While it is possible to distinguish corn pollen and its close relatives from the grass, it is difficult to distinguish the corn pollen (Zea mays) from the pollen of the teosinte weed that is thought to be the ancestor of corn. (Zea sp) without taking into account the greatest scope. Therefore, although pollen grains may provide evidence of the occurrence of domesticated maize, along with pollen grains of other plants when cultivating and cultivating, the maize pollen grains have not yet been must be convincing evidence for this domesticated plant.

Phytoliths are another form of plant fossil microbes that have been preserved for thousands of years. It can be used in the process of distinguishing domesticated corn and wild corn. They are essentially silica or calcium oxalate deposits accumulated inside stem, leaf and root cells. They have a characteristic shape depending on the species. They are still able to preserve even if the tree is burned or decomposed. Scientists have found that it is possible to distinguish microliths in teosinte weed from the ingredients in corn and other grasses, thereby allowing them to date and the location of early cultivation. Phytoliths are also stored in stone and ceramic artifacts used to prepare food.

Jones and his colleagues conducted sediment analysis at San Andrés in Tabasco state on the Gulf of Mexico coast. The analysis revealed information about phytoliths of many domesticated maize varieties as well as the types of plants grown. This data, along with evidence of burning, shows that agronomists appeared in the Yucatan Peninsula about 7000 years ago.

Starch seeds are a new supplement in the archaeological plant toolbox. Corn and grass relatives produce a lot of starch grains with characteristic morphological characteristics. Like phytoliths, they are also stored in sediment and cultural artifacts. Corn is more starchy than its teosinte cousin, corn grain is also much larger than that of wild plants. Plant botanist Dolores Piperno and his colleagues have set many criteria to distinguish starch granules of many different plants. They found that the starch grains of corn and teosinte grass were significantly different in size and other morphological characteristics.

Corn also has rich genetic resources with thousands of varieties adapted to many different environmental conditions. Scientists and corn geneticists have used this information to track the evolution and spread of corn varieties, while reconstructing the history of domesticated corn. For example, the teosinte glume architecture 1 (or tga 1) locus is important in determining phytolith information and morphology, along with other domesticated genes used to write the history of domestication of maize who performed.

All of the above methods are being used by paleontologists, plant research scientists, archaeologists like Jones and colleagues to reconstruct the long history of plant domestication. corn as well as evolution. Many ancient species are adapted to different environmental conditions such as soil conditions, temperature, altitude or drought. Preserving these species as well as knowledge of adaptive and genetic history is extremely important when farmers around the world are facing changes in land and temperature, water supply source. They also have to fight to maintain the supply of food that provides an increasing amount of mouth.