Modern rice emerged 10,000 years ago
New evidence looks set to settle the question of rice’s first domestication. AMY MIDDLETON reports.
The site of the first domestication of rice is a hotly contested issue, with several countries eager to lay claim. A number of locations in China have been put forward, as have the Ganges valley in India, the southern slopes of the Himalayas and various places in south-east Asia.
Shangshan, in China’s Lower Yangtze region, has long been one of the strongest contenders: archaeological artefacts uncovered there contain some of the earliest evidence of rice grown by humans.
Ancient rice remnants in different sites show up as microscopic silica bodies called phytoliths. However, the type – wild or domesticated – isn’t always clear.
Researchers have used radiocarbon dating to place these phytoliths on a timeline, but estimates have been controversial because of the possibility of samples becoming contaminated by older carbon present in the surrounding soil.
In the latest study, a research team led by Xinxin Zuo, a geophysicist at the Chinese Academy of Sciences in Beijing, verified the age of the phytoliths at Shangshan by comparing them with carbon dates from artefacts found in the same sedimentary layer.
The team then examined the structure of the rice remnants, and found that they “are closer to modern domesticated species than to wild species”. This constitutes the earliest known evidence of rice domestication.
“When the domestication of rice began in its homeland, China, is an enduring and important issue of debate for researchers from many different disciplines,” the researchers note.
The study was published in the
Proceedings of the National Academy of Science.
CREDIT: BANAR FIL ARDHI / GETTY IMAGES