As a writer, your sleep schedule is at the whim of your writing urge. If inspiration strikes at 4 a., too bad, no sleep for you. Which generally means that you look your worst when you write your best.
The writer: Someone who spends a lifetime in solitude for the sake of communication. <-- I'm fine with solitude though. Even if I wasn't a writer I'd be alone most of the time, so why not take advantage of it?