Competitiveness among Nandi female husbands.

In the Nandi society in Kenya, custom establishes that a woman’s “house property” can only be transmitted to male heirs. As not every woman gives birth to a male heir, the Nandi solution to sustain the family lineage is for the heirless woman to become the “female husband” to a younger woman by undergoing an “inversion” ceremony to “change” into a man. This biological female, now socially a man, becomes a “husband” and a “father” to the younger woman’s children, whose sons become the heirs of her property. Using this unique separation of biological sex and social roles holding constant the same society, I conduct competitiveness experiments. Similar to Western cultures, I find that Nandi men choose to compete at roughly twice the rate as Nandi women. Importantly, however, female husbands compete at the same rate as males, and thus around twice as often as females. These findings are robust to controlling for several risk aversion, selection, and behavioral factors. The results provide support for the argument that social norms, family roles, and endogenous preference formation are crucially linked to differences in competitiveness between men and women.