The Mystery of Monogamy
解释为何发达社会实行一夫一妻制，而历史上富人多妻。研究发现，发展过程中女性不平等加剧，使男性不平等从妻子数量转向妻子质量。
We examine why developed societies are monogamous while rich men throughout history have typically practiced polygyny. Wealth inequality naturally produces multiple wives for rich men in a standard model of the marriage market. However, we demonstrate that higher female inequality in the marriage market reduces polygyny. Moreover, we show that female inequality increases in the process of development as women are valued more for the quality of their children than for the quantity. Consequently, male inequality generates inequality in the number of wives per man in traditional societies, but manifests itself as inequality in the quality of wives in developed societies.