Scientists explore the history of corn domestication

a new study found that the domestication of maize began nearly 9,000 years ago in what is now central Mexico and is much more complex and subtle than previously thought. Analysis of the genetic inheritance of this ancient grain reveals that the southwestern region of the Amazon basin is the secondary improvement center of early maize. These findings provide new clues to this human-mediated evolution, which produced one of the most important major crops on Earth.
In a related article, the researchers wrote that this remarkable new multi-agent study of the spread of maize into and across northern South America is a good example of recent progress in uncovering the complex history of early crop domestication. Domesticated corn evolved from the species, a wild herb in Mexico that spread rapidly throughout the Americas, filling early agricultural areas and becoming a near-ubiquitous source of food when the Europeans arrived. Although it is widely known that a domestication of maize occurred, the nature of its domestication and its incoming South America remains unclear, and existing archaeological and genomic data do not always match.
researchers sequenced the genomes of corn from South America, which includes domesticated native varieties and ancient corn samples from archaeological discoveries, and compared it with contemporary and ancient corn lineages and those of the world. The results showed that the ancestors of corn arrived in South America only "semi-domesticated". Before the genetic markers of maize domestication were fixed, they were separated from their Mexican ancestors, and the corn linees of South America evolved uniquely , some of which became fully domesticated crops under sustained human selection. By combining its genome discovery with archaeological, paleoeanthic and linguistic data, the authors suggest that this parallel but independent sub-improvement may have begun in the southwestern amazon basin. (Source: China Science Journal)