DR. SARAH C. WALSHAW, Simon Fraser University, Burnaby, Canada, received a grant in May 2007 to aid research on 'Food Production Viewed from the Fields: Contributions from Swahili Ethnoarchaeology on Pemba Island, Tanzania.' Archaeological plant assemblages from several communities on Pemba Island, Tanzania, contain significant amounts of grain and chaff, suggesting that rice and pearl millet were stored in a largely unprocessed form. Ethnoarchaeological research was undertaken among farming communities on Pemba Island, where rice, sorghum, and pearl millet are farmed using non-mechanized techniques (such as hand-harvesting) to model the small-scale tropical farming systems of the Swahili. Observation of, and participation in, farming on Pemba Island helped explain several patterns seen archaeologically. First, hand harvesting eliminated weeds in the field and may be implicated in the infrequency of weed seeds in ancient houses and middens. Second, grains for food and seed were stored in the house to permit monitoring of amount and condition. Third, grains were reportedly stored in their husks to reduce loss from microbial and insect infestation, pest predation, and human over-use and theft. Labor constraints also posed significant pressures in this household-based agricultural economy, leading harvesters to spread the arduous tasks of processing throughout the year -- small amounts of grain were processed for each day's meal as required. This study demonstrates some of the agricultural and social motives for household-based agricultural practices, and provides a model for interpreting archaeobotanical patterns evident in ancient small-scale rice and millet farming systems.
Walshaw, Sarah, 2010. Converting to rice: urbanization, Islamization and crops on Pemba Island, Tanzania, AD 700-1500. World Archaeology 42:(1) 137-154.