Sex Roles: In and Out

Mythbusters is one of the coolest shows on television.

One of their episodes tested the (false) rumor that a cell-phone can set off an explosion at a gas-station.

But static electricity, generated by getting in and out of one's vehicle, can.

The Mythbusters determined by observation that once the pump is running, women get in and out of their cars six times more often than men, creating static electricity build-up that discharges as a spark that ignites gas.  Also, spark-generated gas-station fires are only caused 22% of the time by men.

What gives?  What cultural or evolutionary quirk makes women get in and out of their vehicles so much more often than men?