Mesoamericans were the greatest cultivators in history, but of all their many horticultural innovations none was more lastingly important or unexpected than the creation of maize, or corn as it is known where I come from. We still don’t have any idea how they did it. If you look at primitive forms of barley, rice or wheat set beside their modern counterparts you can see the affinities at once. But nothing in the wild remotely resembles modern corn. Genetically its nearest relative is a wispy grass called teosinte, but beyond the level of chromosomes there is no discernible kinship. Corn grows into a hefty cob on a single stalk and its grains are encased in a stiff, protective husk. An ear of teosinte, in comparison, is less than an inch long, huskless and grows on a multiplicity of stems. It is almost valueless as a food; one kernel of corn is more nutritious than a whole ear of teosinte.
Bill Bryson, At Home: A Short History of Private Life, 2010