corn,mutations,people

​I have been thinking (I Know, that is dangerous!) about the long history of corn and all the generations of people that have participated in corn as we know it today. A lot of what we see today, adaptation of this species to all continents on our planet as well as individual field environments is due to its unique biology and interactions with growers researcher. 
 
About 10000 years ago, someone or maybe several people came upon a mutant in a variety of Teosinte in which the seed (kernel) was larger than most Teosinte seed. Probably already using this species for food, grinding the seed into a flour. This mutant must have been attractive and worth propagating.  Further enhancement was encouraged by the fact that this and surrounding plants had sufficient distance from male and female parts that cross fertilization was common, allowing further mixing of genes.  Selection by those people in Southern Mexico continued to select plants with a combination of genes that had bigger and more kernels, as well as other plant features to support the kernels. Furthermore, these kernels could easily be transported by people passing through and carried further south and north, the genetic breadth and mutations allowing eventual selection of varieties adapted to the northern order of USA, through the tropics of South America to its most temperate environments. 
 
When first European discovered the Americas, they found that native tribes had this plant species as a food crop. As each tribe had multiple years of maintaining and selections among genetic variants, there was already a large genetic pool that would eventually allow the adaptation to other continents.  
 
Today’s growers are doing the same thing, selecting the corn hybrid that most fits their environment and the seed producers have the incentive to respond by searching for the genetic combinations best matching these environments.  The broad genetic base of about 40000 genes spread across the corn’s 10 chromosomes allows for continual selection of the best fit.
 
Corn characteristics of its photosynthesis utilization of highest light intensity, separation of male and female flowers, annual maturity, efficient movement of carbohydrates to kernels supported with a broad genetic base has allowed this crop to become an international source of nutrition for humans.