They suggest that japonica and indica each evolved from O. rufipogon long before rice domestication began and then were independently domesticated in different regions.
Given that forests are home to wild versions of these plants, it would seem to make sense that domestication began in or near forests.
In the centuries between 3500 and 1500 bce, plant domestication began in what had been hunting-gathering contexts, as on the Pacific coast of Chiapas and on the Veracruz Gulf coast and in some lacustrine settings in the Valley of Mexico.
Other genetic studies, however, have suggested that dog domestication began as early as 18,800 32,100 years ago in Europe or that early dogs dating from about 12,000 to 14,000 years ago came from a small strain of gray wolf that inhabited what is now India.
By collating and researching a large number of historical documented observations of goldfish breeding in ancient China, Chen was able to propose that goldfish had originated from crucian and that their domestication began in the Southern Song Dynasty.
This pattern reminded us of some intermediate genotypes when we created recombinant inbred lines between japonica and indica cultivars, and may imply that there was a critical crossing between relatively distant wild species when japonica rice domestication began.
But in a dramatic example of the power of domestication, beginning some 9000 years ago people in Mexico and the U.S. Southwest transformed teosinte into the many-kerneled maize that today feeds hundreds of millions around the world. .
Wayne and his colleagues calculate, based on mutation rates and observed genetic differences in their samples, that dog domestication began between 18,800 and 32,100 years ago, and that canines were well entrenched with people between 15,000 and 20,000 years ago, before humans farmed.
The process of sheep domestication began between 9000 and 11,000 years ago.
Hence, if domestication begun and ended in the Eastern Mediterranean, then we expect to observe limited diversity so far away from the original zone of domestication.
