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Published on: August 22, 2013
Preference for sons and sex ratio in two non-Western societies
E Crognier1, A Baali, M-K Hilali
1UMR6578 du CNRS et Université de la Méditerranée, Faculté de Médecine, 27 bld Jean Moulin-- 13385 Marseille Cedex 05, France. crognier@ciudad.com.ar
Summary
Parental care may not significantly favor sons over daughters, even with cultural preferences for male offspring. Study findings suggest survival rates do not consistently reflect biased investment in sons across different economic strata in Berber and Aymara communities.
Area of Science:
- Anthropology
- Evolutionary Biology
- Sociology
Background:
- Cultural preferences for male descent are observed in traditional agricultural societies facing harsh environments.
- Socioeconomic status can intensify the social valorization of sons over daughters.
- Parental investment bias, favoring sons, is hypothesized to influence offspring survival and sex ratios.
Purpose of the Study:
- To investigate sex-based differences in parental care by comparing child survival rates across economic strata.
- To examine whether cultural preferences for male progeny translate into differential parental investment and survival outcomes.
- To analyze survival data in Moroccan Berber and Bolivian Aymara populations in relation to child's sex and socioeconomic status.
Main Methods:
- Comparative analysis of child survival data from Moroccan Berber and Bolivian Aymara populations.
- Stratification of data by economic status (poor, medium, high).
- Examination of survival differences based on child's sex and age groups.
Main Results:
- Moroccan data: Daughters showed a survival advantage pre-weaning in medium/high strata; poorest boys had higher mortality (ages 10-20).
- Aymara data: Daughters had a survival advantage (birth-5 years) in the medium group; no other significant sex differences by stratum.
- No consistent survival advantage for sons was observed across economic strata in either population.
Conclusions:
- Despite cultural valorization of male progeny, observed parental care differences (indicated by survival) may not significantly favor sons.
- The magnitude of any sex-biased parental care might be insufficient to create detectable differences in offspring survival.
- Environmental and socioeconomic factors may play a more significant role in survival than sex-biased parental investment in these populations.
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