Researchers at the Chinese Academy of Sciences have collaborated with experts from 13 institutions nationwide, including the Institute of Geology and Geophysics of the Chinese Academy of Sciences, Zhejiang Provincial Institute of Cultural Relics and Archaeology, Linyi University, and the Shangshan Site Management Center. By utilizing methods such as phytolith microfossil analysis, they have conducted a study on the origin of rice in the Shangshan cultural area of Zhejiang, uncovering the continuous evolutionary history of rice from the wild to domesticated over 100,000 years. This research provides new evidence for understanding the development of human society and the origin of agricultural civilization, further confirming China as the birthplace of rice in the world and the significant role of the Shangshan culture in the origin of agriculture worldwide. The findings were published online in the international academic journal "Science" on May 24, 2024, Beijing time.
The locations of Shangshan Site (a and c) and Hehuashan Site (b) (Images provided by the Institute of Geology and Geophysics, Chinese Academy of Sciences, and the Institute of Cultural Relics and Archaeology of Zhejiang Province)
The origin of agriculture marks a crucial turning point in human social development, signifying the transition from a hunter-gatherer economy to an agricultural production economy, and initiating the birth of human civilization. Rice is not only the staple food for half of the world's population today but also its cultivation and domestication have had a profound impact on the formation and development of Chinese civilization. When did humans start harvesting and utilizing rice? What was the process from wild to domesticated like? These have long been focal questions of interest in both society and academia.
△ Conceptual Model of the Evolution of Rice from Wild to Domesticated in the Lower Yangtze River Region over 30,000 Years (Image provided by the Institute of Geology and Geophysics, Chinese Academy of Sciences)
For over a century, the origin of rice has been a topic of controversy, with theories suggesting origins in India, Southeast Asia, Assam, Yunnan, among others. Since the 1970s, with the discovery of archaeological evidence of rice at sites like Hemudu, Shangshan, and many others in the middle and lower reaches of the Yangtze River in China, the international academic community has come to recognize this region as one of the important origins of rice worldwide. The key to breakthroughs in research lies in identifying indicators that can distinguish between wild and domesticated rice, potentially revealing the process and mechanisms of human transition from collecting to domesticating wild rice, especially since the Last Glacial Maximum around 26,000 years ago.
In the latest research, the research team led by Lu Houyuan from the Institute of Geology and Geophysics, Chinese Academy of Sciences, based on years of systematic studies on modern wild rice, domesticated rice plants, and rice phytoliths in soil, has established a clear correlation between the increase in the number of fish scale patterns in rice phytoliths in bubble cells and the degree of rice domestication, as well as the enhancement of agricultural traits. They have defined a threshold for distinguishing between wild and domesticated rice based on the proportion of fish scale patterns in phytoliths, establishing criteria for identifying the transition from wild to domesticated rice. By further utilizing phytolith analysis methods and combining various means such as pollen, charcoal, soil micro-morphology, grain size, magnetization, geomorphological surveys, and archaeological excavations, they conducted systematic studies on the natural profiles of archaeological layers at the Shangshan site in Pujiang County, Zhejiang, and the Heluoshan site in Longyou County, establishing a continuous chronological stratigraphic sequence dating back approximately 100,000 years. Through systematic analysis of samples from the stratigraphic sequence, they revealed a continuous trajectory of rice from wild to domesticated in the archaeological layers of the Shangshan site, shedding light on its relationship with human activities and climate change.
The research indicates that as early as about 100,000 years ago, wild rice was already distributed in the lower reaches of the Yangtze River, laying the groundwork for the later utilization and domestication of rice. Around 24,000 years ago, as the climate entered a cold period during the Last Glacial Maximum, humans began collecting and utilizing wild rice, adapting to the cold climate change and exploring new food sources. Approximately 13,000 years ago, intentionally or unintentionally, humans began cultivating wild rice before domestication, initiating the long and complex process of rice agriculture. Around 11,000 years ago, the proportion of phytoliths in domesticated rice rapidly increased, reaching the domestication threshold, marking the origin of rice agriculture in East Asia. This study suggests that the origins of rice agriculture in East Asia and wheat agriculture in the Mesopotamian region were synchronous milestones in human development history, significantly deepening our understanding of the global pattern of agricultural origins.
The continuous evidence from the Shangshan site in Zhejiang over the past 100,000 years, from the distribution of wild rice to its eventual domestication, reveals the complex relationship and lengthy process of rice domestication with climate, human activities, and cultural development. This research has profound implications for understanding the development of human societies, the origins of agricultural civilizations, and the significance of the Shangshan culture.
Related Knowledge:
Phytoliths are non-crystalline silica particles formed by the absorption of soluble silicon by higher plants during growth, transported to various parts such as stems, leaves, and fruits, and precipitated between and within cells.
Cultivation refers to the management of plant growth by humans without altering genetic traits.
Predomestication cultivation involves the intentional or unintentional management of plant growth by humans without altering the genetic traits of wild plants.
Domestication refers to the alteration of plant genetic traits by humans to adapt them to artificial environments.
Last Glacial Maximum (LGM) occurred approximately 26,500 to 19,000 years ago, with global temperatures 5°C to 10°C lower than modern times. Sea levels may have been 120 to 135 meters lower than today.
(CCTV reporter Shuai Junquan, Chu Erjia)
