Measuring Diet Breadth in Paleobotanical Data Using the Shannon-Weaver and Richness Indices

In subsistence studies, diet breadth models commonly rely on two indices, diversity and richness. Diversity is often measured using the Shannon-Weaver information diversity index. Richness is expressed by the number of different taxa represented in an assemblage. In the Tucson Basin after the introduction of maize, two thousand years of stable, low intensity use of maize were followed by 1400 years of comparatively rapid changes in the organization of food production and procurement. Which measure of diet breadth does a better job of capturing the differences between Early Agricultural Period forager farmers and Sedentary Period Hohokam sedentary, intensive-farmers? I evaluate the utility of the Shannon Weaver and Richness indices by comparing diet breadths in paleobotanical data from components at the Las Capas and Julian Wash sites.