Abstract
Growing evidence suggests mothers invest more in girls than boys and fathers more in boys than girls. We develop a hypothesis that predicts preference for girls by the parent facing more resource constraints and preference for boys by the parent facing less constraint. We test the hypothesis with panel data from the Tsimane’, a foraging-farming society in the Bolivian Amazon. Tsimane’ mothers face more resource constraints than fathers. As predicted, mother’s wealth protected girl’s BMI, but father’s wealth had weak effects on boy’s BMI. Numerous tests yielded robust results, including those that controlled for fixed effects of child and household.
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The National Science Foundation (SBR-9731240 and SBR-9904318) funded the research. Thanks go to L. Apaza, E. Conde, J. D. vila, H. Rivas, P. Pache, E. Tayo, S. Cari, J. Cari, M. Roca, D. Pache, J. Pache, and V. Cuata for help collecting data and logistical support. Thanks to M. Gurven and R. Trivers for references on parental discrimination in evolutionary biology, to J. Behrman and J. Hoddinott for suggestions on the econometric analysis, and to R. Trivers, L. Cronk, E. Byron, M. Borgerhoff Mulder, and three anonymous reviewers for comments on earlier versions.
Godoy, Huanca, and Reyes-García are cultural anthropologists affiliated with the Heller School for Social Policy and Management, Brandeis University. Leonard, McDade, and Tanner are biological anthropologists at Northwestern (Leonard and McDade) and the University of Michigan (Tanner). Vadez is an agronomist with ICRISAT. Patel works in a political polling firm in Washington. They have worked together among the Tsimane’, collecting and analyzing panel data to assess the effects of lifestyle changes on farming systems and natural resources (Huanca, Vadez), folk knowledge (Reyes-García), and health and nutritional status (Leonard, McDade, and Tanner).
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Godoy, R., Reyes-García, V., McDade, T. et al. Why do mothers favor girls and fathers, boys?. Hum Nat 17, 169–189 (2006). https://doi.org/10.1007/s12110-006-1016-9
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DOI: https://doi.org/10.1007/s12110-006-1016-9