Abstract
The Hadza foragers of Tanzania are currently experiencing a nutritional shift that includes the intensification of domesticated cultigens in the diet. Despite these changes, no study, to date, has examined the possible effects of this transition on the food collection behavior of young foragers. Here we present a cross-sectional study on foraging behavior taken from two time points, 2005 and 2017. We compare the number of days foraged and the type and amount of food collected for young foragers, aged 5–14 years, in age- and season-matched samples. Compared with 2005, in 2017 fewer subadults left camp to forage, and overall, they targeted a smaller variety of wild foods, with the noticeable absence of wild honey, figs, and tubers. In addition, participants in 2017 were significantly more likely to have attended school. Despite the increased presence of domesticated plant foods in the diet and increased attendance at school, some young foragers continue to be highly productive in collecting wild, undomesticated foods. Despite the preliminary nature of our results, our findings suggest that the range of wild foods targeted by subadults is decreasing as the amount of domesticated cultigens in the diet increases. These data underscore the importance of studying diet composition and foraging decisions across temporal, nutritional, and ecological landscapes.
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Notes
Here, we operationalize “early nutrition transition” as the first stages of the process where societies/individuals become increasingly reliant on domesticated products, while still also collecting and consuming wild foraged foods. Closely coinciding with Popkin’s (1993, 2001) operationalization of the term, populations experiencing these early stages of nutrition transition typically have no indications of non-communicable metabolic diseases (e.g., type II diabetes, hypertension).
We operationalize “subadult” as any child, juvenile, or adolescent under the age of 18 years who falls within the age parameters of the current study.
We define a “mixed-foraging” or “mixed-subsistence” population as any that supplements their foraged diet with domesticated cultigens and/or processed foods, whether through horticulture, pastoralism, donation, purchase, or trade.
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Acknowledgments
We would like to thank the Hadza, who were incredibly generous with their time and patience during the 2005 and 2017 field seasons. Also, we acknowledge the research support and intellectual contributions of Frank Marlowe, recently deceased, a giant whose shoulders we stand on.
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All procedures performed in studies involving human participants were in accordance with the ethical standards of the Institutional Review Board in the Office of Research Integrity at the University of Nevada, Las Vegas (protocol # 1048449–2) and the Tanzanian Commission for Science and Technology (COSTECH) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
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Pollom, T.R., Herlosky, K.N., Mabulla, I.A. et al. Changes in Juvenile Foraging Behavior among the Hadza of Tanzania during Early Transition to a Mixed-Subsistence Economy. Hum Nat 31, 123–140 (2020). https://doi.org/10.1007/s12110-020-09364-7
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DOI: https://doi.org/10.1007/s12110-020-09364-7