13 research outputs found
GEOGRAPHIC CLUSTERING OF THE SECONDARY SEX RATIO IN JAPAN: ASSOCIATION WITH DEMOGRAPHIC ATTRIBUTES
MATERNAL EDUCATIONAL ATTAINMENT AND SEX RATIO AT BIRTH BY RACE IN THE UNITED STATES, 2007â2015
Biological, environmental and socioeconomic determinants of the human birth sex ratio in the Czech Republic
Sex-ratio biasing towards daughters among lower-ranking co-wives in Rwanda
There is considerable debate as to whether human females bias the sex ratio of their offspring as a function of their own condition. We apply the TriversâWillard predictionâthat mothers in poor condition will overproduce daughtersâto a novel measure of condition, namely wife rank within a polygynous marriage. Using a large-scale sample of over 95â000 Rwandan mothers, we show that lower-ranking polygynous wives do indeed have significantly more daughters than higher-ranking polygynous wives and monogamously married women. This effect remains when controlling for potential confounds such as maternal age. We discuss these results in reference to previous work on sex-ratio adjustment in humans