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...

This paper derives the conditions under which fitness-reducing alleles can survive in a long-run stationary equilibrium for a trading population, extending the results in Saint-Paul (2002) for arbitrary systems of sexual reproduction. -- trade ; genotypes ; natural selection ; gene-culture...

The problem with most intergenerational mobility estimates is that unmeasured and inherited abilities prevent us from drawing inferences. In this paper we estimate the intergenerational mobility of schooling and exploit differences between adopted and own birth children to obtain genetically...