Justin Bieber's Hair Evolution From Bowl Cut to Dreads

— -- Let's face it: We can't get Justin Bieber's songs out of our heads, but it's his hair that we can't get out of our hearts.

The singer burst onto the music scene with his memorable blond bowl cut and since then, the Canadian has fascinated us with different colors, styles and trends.

His latest? Bieber, 22, now has dreadlocks. He captioned the photo, "Why."

It's not the first time Bieber's hair has captivated our attention. Here's a look back at some of Bieber's most memorable 'dos: