Mothers in poor condition, here lower-ranking co-wives in a polygynousmarriage, may overproduce daughters because these give them greater fitness returns than sons.
贫困的母亲，在这里指一夫多妻制中地位较低的妻子，可能生更多的女孩，因其健康状况比男孩要好。
2
We apply the Trivers-Willard prediction - that mothers in poor condition will overproduce daughters - to a novel measure of condition, namely wife rank within a polygynousmarriage.