Now I know why I stay up late! (and hate getting up early!)

Got this one from BoingBoing. A blog called Circadiana and one of the posts being Everything You Always Wanted To Know About Sleep (But Were Too Afraid To Ask)

The "owls" have longer periods and "larks" have shorter periods. Period determines phase relationship between the internal clock and the environmental synchronizing cue (e.g., the light-dark cycle), thus longer the period of the clock, later the clock will trigger waking up in the morning or feeling sleepy in the evening, and vice versa. People like me go to bed at 4am and wake up at noon. People with the extreme lark mutation wake up at about 4am, but are real party poopers, snoozing at 7pm or so.

So, I'm an 'owl', eh? I can live with that!