Dissertation Research: Searching for the Origin of Rice (Oryza sativa) in China: An Application of Phytolith Analysis

在Deborah Pearsall博士的指导下，Zhijun Zhao先生将为他的博士论文收集数据。他将前往中国长江中游地区，从一系列考古遗址收集土壤样本，这些遗址跨越了新石器时代，当时定居的村庄生活首次出现。他和他的中国合作者还将从最有可能保存有机遗迹的地区收集土芯，并分析所有收集到的材料中的花粉和植硅体。该项目的目标是深入了解水稻驯化的起源，并根据花粉粒和植硅体（植物组织中形成的硅酸盐体），既可以检测水稻的存在，也可以确定所代表的物种是野生的还是驯化的。从土芯分析中获得的信息将使研究小组能够重建新石器时代的气候变化，并研究文化和环境变化之间的关系。基于广泛的文献回顾和植物学和考古学资料的研究，赵先生假设水稻最早是在长江中游地区驯化的，气候变化提供了近因。 在中国和世界其他地方发生的变化，在大致相同的时间，通常被称为“革命”，因为在这个过程中，各种植物和动物第一次被驯化，陶器第一次出现在考古记录中，一个定居的村庄为基础的生活方式出现。这一过程似乎在中国独立发生，水稻的驯化似乎在这一变化中发挥了重要作用。然而，考古学数据极其稀少，植物遗骸在考古学记录中没有得到很好的保存。因此，无法确定驯化发生在何时何地，以及驯化发生在中国新石器时代的哪个阶段。没有这些知识，就很难解开推动这场沿着“革命”的因果链条。花粉，尤其是植硅体，在考古记录中保存得相对较好，赵先生的顾问Pearsall博士开发了一套钥匙，可以根据它们产生的植硅体来识别野生稻和家养稻。赵先生将在中国应用这种技术。 这项研究之所以重要，有几个原因。它将为许多考古学家提供感兴趣的数据。它将对人类史前史上最重要的变化之一产生新的见解，并将有助于培养一位有前途的科学家。

Under the direction of Dr. Deborah Pearsall, Mr. Zhijun Zhao will collect data for his doctoral dissertation. He will travel to the Middle Yangtze region of China and collect soil samples from a series of archaeological sites which span the Neolithic period when settled village life first emerged. He, and his Chinese collaborators will also collect soil cores from areas most likely to preserve organic remains and they shall analyze the pollen and phytoliths in all of the materials collected. The goal of the project is to gain insight into the origins of rice domestication and on the basis of pollen grains and phytoliths, which are silicate bodies formed in plant tissues, it will be possible both to detect the presence of rice and to determine whether the species represented are wild or domesticated. The information derived from analysis of soil cores will allow the team to reconstruct changing climate over the Neolithic period and to examine the relationship between cultural and environmental change. Based on an extensive literature review and study of both botanical and archaeological information, Mr. Zhao postulates that rice was first domesticated in the Middle Yangtze region and that climatic change provided the proximate cause. The changes which occurred in China and other parts of the world at roughly the same time are often referred to as a `revolution` because it was during this process that a variety of plants and animals were first domesticated, that pottery first appears in the archaeological record and that a settled village-based way of life emerges. This process appears to have occurred independently in China and the domestication of rice seems to have played an important role in this change. Archaeological data however are extremely scanty and plant remains are not well preserved in the archaeological record. Therefore it is not possible to determine either just when or where domestication took place and at what stage in the Chinese Neolithic domestication occurred. Without this knowledge it is difficult to unravel the chain of cause and effect which propelled the `revolution` along. Pollen, and especially phytoliths, are relatively well preserved in the archaeological record and Mr. Zhao's advisor, Dr. Pearsall has developed keys which allow the identification of both wild and domestic rice on the basis of the phytoliths they produce. Mr. Zhao will apply this technique in China. This research is important for several reasons. It will provide data of interest to many archaeologists. It will shed new insight into one of the most significant changes in human prehistory and will assist in the training of a promising scientist.