By Chinese Academy of Sciences Headquarters

Research has traced rice’s domestication over 100,000 years, establishing China as the birthplace and highlighting Shangshan culture’s role.

In a new study published in Science, scientists have traced the extensive 100,000-year evolution of rice from its wild forms to domesticated varieties using phytolith analysis and other techniques, confirming that China is the birthplace of rice (Oryza sativa) and shedding light on the origins of agricultural civilization.

Conducted in the Shangshan cultural area of Zhejiang, this collaborative effort involved the Institute of Geology and Geophysics of the Chinese Academy of Sciences (IGGCAS), the Zhejiang Provincial Institute of Cultural Relics and Archaeology, Linyi University, the Administration Center of Shangshan Site, and experts from 13 other national institutions. The findings emphasize the critical role of the Shangshan culture in the early stages of global agricultural history.

The Origin of Agriculture and Rice

The origin of agriculture marks a crucial turning point in human society, transitioning from a hunter-gatherer economy to an agricultural production economy. Rice, as the staple food for half of the world’s population, has had a profound impact on the formation and development of Chinese civilization through its cultivation and domestication. Questions such as when humans began to explore wild rice and how the process of domesticating wild rice occurred have long been the focus of various disciplines.

Evolution of Rice Cultivation

Over the past century, the study of rice origins has been a controversial topic. It was not until the discovery of rice-related archaeological evidence beginning in the 1970s at sites such as Hemudu, Shangshan, and other locations in the middle and lower reaches of the Yangtze River that the international scientific community began to recognize this region as a significant area for the origin of rice. However, finding long-preserved identifiers that could distinguish wild and domesticated rice in the Yangtze River basin since the last glacial maximum and uncovering the processes and mechanisms of human collection and domestication of wild rice remained key challenges in this research.

Methodology and Findings

In this study, a research team led by Dr. Lyu Houyuan of IGGCAS built on years of systematic research on phytoliths in modern wild and domesticated rice plants and soils. The researchers determined that the increase in the number of fish-scale facets on rice bulliform phytoliths correlates with enhanced domestication and agronomic traits. By establishing the threshold for distinguishing wild rice from domesticated rice based on the proportion of bulliform phytoliths with fish-scale facets, they set standards for identifying wild and domesticated rice.

Discovering Rice’s Past through Stratigraphy

The researchers used phytolith analysis in combination with pollen, charcoal, soil microstructure, grain size, magnetic susceptibility, geomorphological surveys, 14C probability density analysis of archaeological sites, and archaeological excavations to conduct systematic studies of the archaeological stratigraphy and natural profiles of the Shangshan site in Pujiang County and the Hehuashan site in Longyou County, Zhejiang.

Using Bayesian models of high-precision optically stimulated luminescence ages and phytolith 14C ages from these sites, they established a continuous chronological sequence dating back about 100,000 years. Systematic analysis of samples from these stratigraphic sequences revealed the continuous trajectory of rice from wild to domesticated within the stratigraphy of the Shangshan cultural site area and its relationship to human activity and climate change.

Key Milestones in Rice Domestication

The researchers suggested that wild rice was already widespread in the lower Yangtze region about 100,000 years ago, setting the stage for subsequent rice use and domestication. Around 24,000 years ago, as the climate began to enter the Last Glacial Maximum, humans began to collect and use wild rice, indicating an effort to explore new food sources in response to a cooling climate. Around 13,000 years ago, humans began pre-domesticating wild rice. About 11,000 years ago, the proportion of domesticated rice phytoliths increased rapidly, reaching domestication thresholds and marking the origin of rice agriculture in East Asia.

Implications for Global Agriculture

This study demonstrates that the origins of rice agriculture in East Asia and wheat agriculture in Southwest Asia were synchronous, representing a significant milestone in human development and greatly deepening our understanding of the global origins of agriculture.

Conclusions on Rice Domestication

The 100,000-year continuous evidence from the distribution of wild rice to its eventual domestication at the Shangshan cultural site reveals the complex relationship between rice, climate, human activity, and cultural development. It also highlights the prolonged domestication process of rice. The research has received high praise from peer reviewers, who consider this innovative discovery a major contribution to the study of human––rice co-evolution.

This work has significant implications for our understanding of human social development, the origins of agricultural civilization, and the significance of Shangshan culture.

Reference: “Rice’s trajectory from wild to domesticated in East Asia” by Jianping Zhang, Leping Jiang, Lupeng Yu, Xiujia Huan, Liping Zhou, Changsheng Wang, Jianhui Jin, Xinxin Zuo, Naiqin Wu, Zhijun Zhao, Hanlong Sun, Zhaoyuan Yu, Guoping Zhang, Jiangping Zhu, Zhenlei Wu, Yajie Dong, Baoshuo Fan, Caiming Shen and Houyuan Lu, 23 May 2024, Science.

Published Date: August 21, 2024