Drs. Deborah Pearsall and Dolores Piperno will collaborate on a three year project to develop the application of phytolith analysis to archaeological materials. Phytoliths are small bodies of silica which are deposited within plants and are usually preserved in soil after death and decomposition occurs. Although one species of plant may produce phytoliths of many shapes, and very few shapes are restricted to a single species, it is possible to examine phytolith assemblages and make some species identifications. Drs. Pearsall and Piperno will conduct a multistage research project to further archaeological application of phytolith analysis. They will examine taxonomy, determine the best methods of soil processing to extract phytoliths, develop improved identification criteria, and finally work on quantification procedures. The result will be a series of tools of direct archaeological use. Only under the most unusual conditions are plant remains preserved in archaeological sites. Thus, because plants play such an important dietary role, it is extremely difficult to reconstruct prehistoric diets. In tropical areas of the world, where preservation is extremely poor, this problem is particularly acute. Phytoliths, because they are so durable, provide a potential way around this problem and therefore merit attention. However, because of the lack of one to one correspondence between phytolith species, analysis poses difficulties. This research should help to solve this problem. The project is important because it will provide archaeologists, as well as paleobiologists, with a valuable tool which should be useful in many parts of the world and periods of time.