Corn journey continued

Ancient corn breeders spent a few thousand years working with the teosinte mutations, further adapting them to human culture.  They changed an ‘ear’ from having two rows of kernels to a cob with at least 8 rows of seeds. The web site http://en.ancientmaize.com, traces the migration of corn from the southcentral Mexico origin to the south and then the north over the next thousands of years.  Maize does produce fertile seed when crossed with Teosinte and surely that occurred frequently as the breeders saved the best adapted to their environments and food needs. 
 
Corn kernels must have been easily transported and traded as neat little packets of food.  One seed could be multiplied to a couple hundred in only one season. It became the main ag product for the Astecs in Mexico, the Inca in the mountain chain from the Ecuador thru Peru and Chile, and the Mayan regime in the lowlands of central America. All three large regimes formed about 5000 years after the first domestication of maize and became major sources of further development of the crop. Within each geographical environment, selection of plants best fit to both the successful reproduction and the local food and culture needs, distinct populations, or races, of corn followed.  In addition to those doing selections in the large regimes there were multiples of smaller groups also selecting corn varieties that fit their needs. Although selection for food production was primary, selection resulted in a range of internal leaf, stem and root structures had to occur to meet the challenging and different environments.