Not that anon, but its pretty obvious. Thousands of years ago women were the ones who took care of the children, gathered berries and grasses, and took care of the home. Men hunted, protected the women, and made sure they where having babies. Now in the present we still have that hunter gatherer mindset that makes us be picky on a mate by how they can provide for us, a woman who is "sexy" in the traditional way is more fertile and therefore can have more children. A man who has a lot in the bank can sustain a family and protect it if they have some sort of financial crisis, and women want that.