We test two hypotheses, based on sexual selection theory, about gender differences in costly social interactions. Differential selectivity states that women invest less than men in interactions with new individuals. Differential opportunism states that women's investment in social interactions...

Using an original dataset describing the career history of some 16,000 senior executives and members of the non-executive board of US, UK, French and German companies, we investigate gender differences in the use of social networks and their impact on earnings. There is a large gender wage gap:...