Another day, another hairstyle. That may as well be the mantra for pop star Rihanna who ditched her platinum blonde strands in exchange for an edgy, jet black, cropped coif at the MTV Video Music Awards. It's not uncommon for Rihanna to switch up her hair. In fact, in the past six months, the diva has worn more hairstyles than many of us would wear in six years. Let's take a look back at the evolution of the ultimate hair chameleon.