Of Cereal and Civilization - Archaeology Magazine Archive


Of Cereal and Civilization	Deceber 11, 2006

A scholar investigates the beginnings of agriculture in China.

If, as Napoleon is said to have remarked, an army travels on its stomach, the same is certainly true of civilizations. That is why the ancient cultivation of cereals including rice across China has been studied so extensively. Tracey Lie Dan Lu, an associate professor of archaeology at the Chinese University of Hong Kong, recently published a multidisciplinary analysis of cereal cultivation in China in Asian Perspectives, reconstructing paleoclimates, analyzing genetic studies, considering artifacts, and describing first-hand experiments she conducted. ARCHAEOLOGY spoke with Lu about her work.

Tracey Lie Dan Lu cuts a wild rice stalk at a South China pond during a tool-using experiment. (Courtesy Tracey Lie Dan Lu) [LARGER IMAGE]

How did you become interested in studying the development of agriculture in China?
It was the topic of my Ph.D. dissertation, which was published by British Archaeological Reports in 1999. My supervisor was Peter Bellwood of the Australian National University, who has been working on this topic for more than 30 years.

On what time period and geographic area did your research concentrate?
Basically I focus on the period from the terminal Pleistocene to the mid-Holocene [13,000 years ago onward], which is a period when the transition from foraging to farming occurred in the landmass called China today. At present I work on the Yangzi River Valley, South China, and Hong Kong, focusing on the proposed expansion of rice agriculture from the former to the latter. I am also working on the exploitation of tubers in South China, particularly taro.

What are the different types of cereals your recently published analysis considers? How does rice fit in?
There are several major domesticated cereals in the world, namely barley, foxtail and broomcorn millet, maize, rice, and wheat. Their genetic structures and habitats are different, but they are all staple food for human beings. Rice is one of these.

What methods are used to determine ancient climates and environments?
There are many methods: flotation sieving, pollen and zooarchaeological analysis, chemical analysis of soil, isotopic analysis of ocean deposits, etc., are commonly used. We are trying to reconstruct ancient climates and environments by studying the past vegetation, fauna, soil, and other natural deposits.

All these methods have some limitations. For example, in 2002 I collected soil samples from a cave in South China for pollen and phytolith analysis, then I invited a biologist to study the current vegetation in the vicinity of this cave, and I compared the results. There are discrepancies. In other words, some plants aren't found in the pollen and phytolith profiles. I think it is very important to integrate different methods.

What can studying the paleoclimate of China tell us about the origins of cereal cultivation?
There are many different hypotheses about the origin of cereal cultivation. Studies conducted in the Middle East indicate that the origin of agriculture might have related to climatic and environmental changes. Is this also the case in China?

I think human beings live in different environments and develop different cultures. So, why did some groups cultivate grasses while others did not? What were the causal factors for some peoples to try a new subsistence strategy? Did climatic and environmental changes play a vital role on this change? Did people cultivate cereals because they were storable, which is very important for groups living in a temperate ecozone, or for other reasons? I think the study of past climates and environments in China will help us to understand why and how cereal cultivation occurred, and the dynamics of nature, human beings, and their cultures in prehistoric China.

Why did cereal cultivation occur in China at all?
The idea of rice cultivation indigenously occurring in China was first proposed by a Chinese agronomist in 1948. Based on current data, I think that the seasonal fluctuation of natural resources in the temperate zone would be an important factor. But we still have to work on this question.

Experimental freshwater shell tool for harvesting grain (Courtesy Tracey Lie Dan Lu) [LARGER IMAGE]

How can tools found from this time period reflect the diet the people were consuming?
Residues and use-wear patterns on tool surfaces can provide important information for us to understand people's diet. Based on use-wear analysis, some small flint flakes were used as harvesting tools in the Yellow River Valley by 10,000 years ago. Of course, sickles were found in this area after 8,500 years ago. The earliest harvesting tools in the Yangzi River are not clear yet. I am going to work on tools found in Shangshan to investigate this question.

What does ceramic vessel shape tell us?
Ceramic vessel shapes tell us a lot of things. Different types of ceramics might have been used for different functions, produced by different clays and techniques, with different meanings and symbols, and even from different areas. By studying ceramic vessel shapes, we can understand the past natural resources (clay and other materials used) available and exploited by human beings, material culture (techniques and food culture etc.), social structure (labor division or symbols of social status), cultural contacts and exchanges (ceramics from other cultures), and even a bit of cognitive aspect (decorative motifs, changes of motifs) of past human beings.

Describe Shangshan, the new archaeological site described in your paper. How is it different from other sites?
Shangshan is very interesting. First, it is an open site with remains of rice in the lower Yangzi River Valley, dated to between 11,000 and 8600 years ago (after calibration). This is the earliest open site found in this area so far with rice remains. Both Xianrendong and Diaotonghuan in the lower Yangzi Valley are caves and are dated earlier than Shangshan, whereas the open sites of Pengtoushan and Bashidang in the middle Yangzi Valley are roughly contemporaneous or slightly later than Shangshan. But the stone tools and pottery of Shangshan are very different from all these sites. So, if there are no mistakes on radiocarbon dating, Shangshan is a very important site for us to understand the origin of rice cultivation in China, because of its location, its relatively early dates, and its unique tools and pottery.

What do the differences in tools and ceramics between Shangshan and nearby Xianrendong indicate?
Geographically and chronologically, Shangshan is between the Xianrendong and Diaotonghuan assemblages of the middle Yangzi Valley and the well-known Hemudu culture in the lower Yangzi Valley. Culturally, Shangshan is quite different from the others. As Shangshan is dated much later than Xianrendong, the question is whether the former developed from the latter, or whether there were cultural contacts and exchanges between the two. Shangshan is still being excavated and a lot of research is still ongoing, so I cannot draw a conclusion at this moment.

How can you track the spread of rice cultivation across time and space in China?
I primarily base my analysis on archaeological data, particularly rice remains found in archaeological sites and absolute dates of these sites. I should say that as both flotation sieving and phytolith analysis have only been applied to archaeological study in mainland China after the 1990s, there might have been rice remains from sites excavated at early dates that were not detected. In other words, the current understanding of rice expansion may not be complete.

How does domesticated rice differ from wild rice, and what influence did humans have on encouraging these differences?
Domesticated rice differs from wild rice in terms of genetic structures and biological characteristics. In recent years, geneticists have done great work on this topic, identifying genes that control the biological characteristics of both wild and domesticated rice. This information is very helpful for archaeologists. Biologically, based on my own experiments and observations, wild rice produces much fewer grains than its domesticated counterpart, always shatters its mature seeds, and has a very low germination rate. All these are problematic for human beings if we want to collect and cultivate it as food. Domesticated rice, on the other hand, produces much more grains, usually does not shatter its ripe seeds, has a much higher germination rate and a simultaneous growth cycle, all very convenient characteristics for humans who want to cultivate and harvest the plant. According to genetic studies, these characteristics of domesticated rice are the result of mutated genes of wild rice.

Theoretically, humans should have influenced the changes from wild to domesticated rice mainly by continuous cultivation and selection of wild rice with mutated biological characteristics of more seeds, tough rachis, higher germination rates, etc. But we are not sure how long this process would have taken. It might have taken more than a hundred years; it might have been shorter. At any rate, it may be very difficult for us to convincingly test the above hypothesis by cultivation experiments, unless we have an institute to do this over several generations.

What do genetic studies tell us about cereal cultivation?
I think genetic studies tell us about the progenitors of domesticated cereals, the genes and other chemical materials controlling the biological characteristics and mutations of the cereals, etc. In short, the natural force and structure of cereals that facilitates the transition from wild to domesticated plant.

Describe your experiments to learn about cereal cultivation. Did you fashion and use tools like the ones used by prehistoric people?
I usually set up the objectives and consider methods before beginning my experiments. It needs to be clear what the purposes of the experiments are, what sort of data I want to collect, how to control the experiments, etc. I cannot say that I produce and use tools exactly like prehistoric people, because no one is certain how these tools were produced and used such a long time ago. But I do my best. I usually learn from ethnographic data, and observe the marks, scars, residues, and use-wear patterns left on tools, before making and using my own replicas. Of course, previous studies in this field are also very important references for me.

What did you learn from your experiments?
I have learned a lot from experiments. I learned how to produce stone and other tools; the skills required, production behavior, time and labor required, how to use the tools, their efficiency, etc. All this information helps me understand the prehistoric tools. I also learned that a certain mental "map" was needed before making the tools. And I learned that ancient humans must have passed their knowledge from generation to generation, for we have seen tools over a very long period of time illustrating similar techniques and features.

What can be learned through ethnographic studies?
Ethnographic data are also very useful for us. I am very impressed by both Lewis Binford's work and an unpublished Australian National University Ph.D. thesis written by Scott Cane ("The Desert Camp"). The latter is a very detailed account of the life, tools, and culture of a band of Australian hunters and gatherers in the 1980s. These data really stimulate my thinking. When I did my project in South China, I also studied the lifestyle and tools and other items used by local villagers. From ethnographic studies we can learn about traditional farming techniques, annual working schedules of traditional farmers, labor input, production rate, tools required, and the efficiencies of different farming tools.

What does the analysis of cereal cultivation tell us about the societies that existed in early China?
One of the major implications is that cereal cultivation did produce a profound impact on social changes in prehistoric China. The societies seem quite egalitarian at the very beginning of cereal cultivation, or when cereal cultivation was probably not the major subsistence strategy. However, after cereal cultivation became a dominating economic activity, societies rapidly changed. Current archaeological data suggest that stratified societies occurred almost right after the occurrence of large-scale cereal cultivation in China. By "large scale" I meant that there were substantial remains of rice or millet found in archaeological deposits, like in Bashidang or Jiahu.

How does study of cereal cultivation in China relate to the development of agriculture worldwide?
The landmass called China today is one of several regions where agriculture occurred independently. Cereal cultivation is an important part of agriculture. In addition, prehistoric agriculture in China also influenced other cultures in East and Southeast Asia. So the study of cereal cultivation in China can be viewed as part of the study of the development of agriculture in the prehistoric world, and data in China can contribute to our understanding of this issue in a global sense. It can also tell us about whether there is a universal trajectory for cultural development in different parts of the world, what will be the common features and local characteristics of various prehistoric cultures, how humans and nature interacted, and how humans in different environments developed their own subsistence strategies and cultures, etc. In short, the diversity and universality--if there is one--of prehistoric cultures.

What is your next avenue of study?
I am still working on the prehistoric subsistence strategies (not just cereal cultivation) in South China and Hong Kong. My next project will be on human exploitation of tubers, particularly taro, in prehistoric South China. I have found remains of taro starch in a prehistoric cave in South China, and would like to tackle this issue in my future study.