If you're a male born to a father who's a strong and enduring community leader, you're far more likely than your less fortunate peers to become a leader yourself, due to the wide range of social advantages accruing from your dad's position.
And even if your old man isn't a leader, other men in your community are more likely to take you under their wing than your sisters, lavishing attention on you and showing you the ropes.
Sound like the basic description of an old boys' network?