Journal of Archaeological Research, Vol. 7, No. 1, 1999 Recent Research in Paleoethnobotany Christine A. Hastorf1 This article discusses paleoethnobotanical research and results presented in the recent literature. Although archaeobotany is a fairly recent addition to the study of the past, it now encompasses a diverse range of techniques, analyses, and new results. Issues that are prominent in this archaeological subdiscipline include the origins of agriculture, resource use, environmental reconstruction, anthropogenic environmental change, political-economic change, plant cultivation and crop production, plant processing, consumption (diet), and site deposition. Some of the plant identification methods for macrobotanical remains include morphology using light microscopes, histology with the scanning electron microscope, and statistics. The study of microbotanical remains has expanded greatly and now includes pollen, phytolith, chemical, and molecular analyses. KEY WORDS: archaeology; plants; archaeobotany; paleoethnobotany. INTRODUCTION The archaeological subdiscipline of paleoethnobotany has expanded greatly during the last 20 years. First practiced in Europe by botanists such as Heer, who looked at plants from archaeological Swiss lake-dwelling sites in the 1850s, it was truly launched as a modern research program in North America by Volney Jones in 1941. In the New World the discipline is usually termed "paleoethnobotany" and is defined as "the analysis and interpreta- tion of archaeobotanical remains to provide information on the interactions of human populations and plants" (Popper and Hastorf, 1988, p. 2). This approach to plant-human interrelationships adds a dynamic aspect to the study of ecological and anthropological questions. Many active scholars in 1Department of Anthropology, University of California, Berkeley, California 94720. 55 1059-0161/99/0300-0055$16.00 C 1999 Plenum Publishing Corporation 56 Hastorf Europe have the same perspective (Hillman and Davies, 1990; Miller, 1995; van Zeist et al., 1991, p. vii), but they use the term "archaeobotany." This difference in names causes some confusion, because in the New World ar- chaeobotany refers the specific processing and identification of plant ma- terials rather than the interpretation of the results. Plants are essential to human existence. Until the last few hundred years of human history, most things that humans dealt with came from either plants or animals. Common daily tasks such as getting food, food preparation, cooking, eating, ritual, shelter construction, and tool use pri- marily were accomplished using plant matter. Plants were charged with symbolic importance that colored every human interaction with them, add- ing to their technical and biological importance. Thus plants also are im- portant to archaeologists. But it is not easy to reconstruct and understand the use and meaning of each plant in the past. Whether we focus on the more commonly uncovered charred, waterlogged, and desiccated macrore- mains or pollen, phytoliths, and other molecular microremains, we obtain only a partial view of the vast universe of past human-plant interactions. Radically diverse preservation conditions and the fact that most plant mat- ter observed on sites is commonly a reflection of mistakes and residues rather than initial acts of usage continue to challenge this subdiscipline. A search of the archaeological journals of 20 years ago reveals that ar- chaeobotanical studies were less common than analyses of animal and human bones. But this pattern is changing as collecting and processing techniques, analytical methods, and interpretations are increasingly implemented, codi- fied, and published. With systematic recovery techniques used at most exca- vations, we now are seeing a fuller picture of past lifeways and long-term human impacts on the environment. In the last 10 years or so many fine examples of paleoethnobotanical research and archaeobotanical studies that report on food, foraging, crops, agriculture, and vegetation have been pub- lished (Ford, 1985; Greig, 1989; Harris and Hillman, 1989; Hastorf and Pop- per, 1988; Miller and Gleason, 1994; Neusius, 1986; Pearsall, 1989; Piperno, 1988; Renfrew, 1991; Scarry, 1993; Smith, 1992, 1995; Sobolik, 1994; van Zeist and Casparie, 1984; van Zeist et al., 1991; Zohary and Hopf, 1993). There also are some bibliographic articles such as Bonavia and Kaplan (1990) and the annual section in Journal of Ethnobiology that reports on recent dis- sertations of interest to paleoethnobotanists. The journal Vegetation History and Archaeobotany has been in print since 1991. Equally influential in pa- leoethnobotanical expansion is the regular inclusion of plant analysis in con- tract archaeology worldwide. This research has contributed substantially to data as well as methodology, although it has been harder to learn about these results due to different strategies of dissemination. Recent Research in Paleoethnobotany 57 Why was this subdiscipline peripheral in field archaeology for so long? Part of the reason is the specialized training that archaeobotanists must have in addition to archaeology, although such detailed training is increas- ingly essential in all subfields of archaeology. In part, I believe that the slowness of regular incorporation also is due to the less visible nature of charred plant remains on sites compared to bones, ceramics, or lithics. Ex- cavators normally cannot see most plant remains with the naked eye and thus cannot use them in their on-site contextual interpretations. It is often many months later that the botanical data enters the discussion, and usually well after the cultural contexts are established and interpretations have been made. This position of archaeobotany in much of archaeology's history per- haps also occurred because of the implicit view that plants were lowly items, interacting with human society primarily in the household spheres of hearth, food processing, fuel gathering, cooking, and eating. These tasks are commonly women's domains. Such household aspects of life perhaps were not thought to be important avenues of study when big questions could be addressed, such as the origins of the state or the rise of complexity. It is as if plants did not participate in or reflect these larger changes. Only recently have state-level questions been addressed with botanical data. On the other hand, the origins of agriculture and environmental reconstruction are archaeological questions that draw regularly on botanical information. Even in models about the onset of agriculture Watson and Kennedy (1991) have pointed out how it is implied that men initiated the process. Archaeobotany also is very labor intensive, so that plant analysis is costly. As Gero (1985) has noted, female archaeologists have tended to be the detailed, small item, laboratory/museum analysts, not valued as highly as field workers in the greater discipline. These two effects have perhaps created a sense of lesser impact in archaeology. Yet despite these images, paleoethnobotany is definitely productive and providing substantive input into broad archaeological issues. This overview highlights some of the important directions in the sub- discipline between 1988 and 1995. I have focused this literature search on issues raised in major books and international journals. The most regularly presented results are the macroremains of charred plants. Pollen is impor- tant, of course, but it tends to be used in the examination of paleoecological and off-site environmental questions (Bottema, 1995; Edwards, 1991b), al- though on-site examples exist (Tipping, 1994). There is an increasing number of exciting microbotanical techniques in the literature, including the investigation of mineralized plants (Scott, 1989), phytoliths (Pearsall and Piperno, 1993; Rapp and Mulholland, 1992), isozymes (Doebley, 1990; Quiros et al., 1990), DNA (Brown et al., 1993; Rollo et al., 1991), chemical 58 Hastorf analyses (Evershed, 1993; Hillman et al., 1993), plant isotopes (Hastorf and DeNiro, 1985), and coprolites (Holden, 1991; Reinhard et al., 1991). These diverse techniques are being applied more often and increasingly help con- tribute to our knowledge of past human lifeways. METHODS One of the most important domains in a discipline's maturation is the development and implementation of effective field and laboratory methods. Macrobotanical remains are investigated primarily by morphol- ogy and histology. Studying morphology with a light microscope is by far the most common identification method. Microbotanical remains must al- ways be analyzed using more high-powered microscopes, chemically, or molecularly. New methods range from processing technologies such as Gu- merman and Umemoto's (1987) siphoning for submerged plant parts in the flotation machine, to Wagner's (1988) systematic testing of recovery rates of various flotation machines. Pearsall's (1989) Paleoethnobotany has become a very important text for methodology. The book reviews basic excavation and soil collection methods all the way through processing of pollen and phytolith extracts. It offers more detail than introductory ar- chaeology textbooks and is in the process of being updated for a second edition. Systematic Sample Collection The systematic collection of samples of sufficient size is an important part of good analysis. Brady (1989) points out the need for diligence in collection methods in his discussion of the importance of systematic flo- tation for wood analysis. While