Asian rice refers to the most widespread member of the genus Oryza, Oryza sativa, the species domesticated in the Yangtze River basin between 13,500 and 8,200 years ago. Under civilization, it became the most widespread food for humans in the world. Nearly all of the rice found in the Fifth World comes from this species. Humans have genetically modified it for millennia, first using traditional domestication techniques, and later with more specialized lab equipment. Varieties like “golden rice” (which takes on a yellow color because of the extra beta carotene in it) have hybridized thoroughly and gone feral, creating a wide variety of rices found across the world.