We evolved as hunter-gatherers. Hunting requires plenty of skill, that is obvious. Compared to the male hunting, female gathering seems a pretty simple task. What I want to show is that the occupation of gathering wild fruits and vegetables is far from simple. It is a highly information intensive occupation.

A tree full of fruits is a temporary store of valuables you encounter by chance. The female that finds it comes home with enough fruits for her family, and one important bit of information. Where others can find was she has.

Who should she share that information with? She should share it with someone who will return the favour another day, so she can get fruits and vegetables another time. The best person to share that with is the one that always seems to be in on the latest finds. She is the most likely to be able to let you in on the next bargain to be had.

This is why it is important as a woman to always show you are in on the latest finds. It will get others to share the information on their finds with you, which in the end is what gets you that regular stream of fruits and vegetables you and your children need.

Fashion is a signal between women intended to sort the ones in the know, from the ones out of it. Women still dedicate a lot of effort to keeping up with the latest finds, because once it really was a matter of life and death.

For a more complete explanation:
http://adriaanb.blogspot.com/