Testosterone, which induces sexual differentiation of the male fetus, is believed to transfer from males to their littermates in placental mammals. Among humans, individuals with a male twin have been found to exhibit greater masculinization of sexually dimorphic attributes relative to those...

In all Western societies women earn lower wages on average than men. The gender wage gap has existed for many years, although there have been some important changes over time. This volume of collected papers contains extensive research on progress made by women in the labor market, and the...

Testosterone, which induces sexual differentiation of the male fetus, is believed to transfer from males to their littermates in placental mammals. Among humans, individuals with a male twin have been found to exhibit greater masculinization of sexually dimorphic attributes relative to those...