Leftist girls, rightist boys: the effect of fatherhood on politics

“While it is true that men biologically determine the sex of their children, recent studies seem to prove that women with higher levels of testosterone — who are more likely to display dominant, positive behaviors — seem to produce more sons than daughters. Women with lower levels of testosterone, who are more likely to be empathetic and better listeners, tend to produce more daughters. It could be that the women who are most likely to produce daughters pick a partner who is closer to her more empathetic attitude to life,” he said. “Hence people who are already more liberal may produce more daughters and those who are already conservative may produce more sons.”