Experimental results are reported from Ultimatum and Public Goods Games performed among the Machiguenga of the Peruvian Amazon, the Mapuche and Huinca of southern Chile, and US control groups in Los Angeles and Ann Arbor (Michigan). The chapter begins with a brief ethno‐historical sketch of the Machiguenga, Mapuche, and Huinca, then the Ultimatum Game methodologies used are sketched and the results presented. Next, the Public Goods Game methodologies used are described, and those results presented – first for the Machiguenga/American comparison and then for the Mapuche/Huinca experiment....

Experimental results are reported from Ultimatum and Public Goods Games performed among the Machiguenga of the Peruvian Amazon, the Mapuche and Huinca of southern Chile, and US control groups in Los Angeles and Ann Arbor (Michigan). The chapter begins with a brief ethno‐historical sketch of the Machiguenga, Mapuche, and Huinca, then the Ultimatum Game methodologies used are sketched and the results presented. Next, the Public Goods Game methodologies used are described, and those results presented – first for the Machiguenga/American comparison and then for the Mapuche/Huinca experiment. Three findings are emphasized: first, results from both the Ultimatum (bargaining) and Public Goods Games indicate much greater between‐group variation than previous work has suggested; second, if individual economic decisions vary as a consequence of differences in individuals’ circumstances, then variables such as wealth, household size, age, and sex should provide some explanatory power, but in fact individual‐level economic and demographic variables do not account for much, if any, of the variation found; and finally, despite the failure of individual‐level variables to explain variation, the results seem to reflect group‐level differences in the economic life of these groups, as captured in numerous ethnographic accounts. Some theoretical and methodological points related to the findings conclude the chapter.