I am always amazed/impressed by the writers (and other people I know) who say they get up early in the morning (like at 4 AM) to "get things done" while the rest of their household is still sleeping. Some of this amazement is that they can have the discipline and focus to be productive when they know they're going to have to stop in just a couple of hours to get ready for work etc. I tend to like my writing time (or any other kind of "me" time for that matter), to be more open ended.
I am also amazed that anyone can go to bed early enough get a good night's sleep while getting up that early. I've always needed eight hours of sleep to feel my best, and so getting up at 4 AM would require my being asleep by 8 PM. Yipes.
I haven't gone to bed that early since I was a little tyke, and even then, it was resentfully. I never fell asleep right off and often snuck a flashlight under my covers to read. When my mom caught me at it (she and Dad stayed up until midnight or so), she'd confiscate my book, and I'd have to tell myself stories until I finally got sleepy. The habit persists to this day, and some of those stories became the nuclei of things I've tried to write over the years.
As an adult, if I try to go to bed earlier than midnight, I'll lie awake until God knows when. I'm familiar with the insomniac's relentless mantra. "If I fall asleep now, I'll still get 5 hours...." And counting. But if I go to bed later, I tend to drop right off.
It really sucked when I had jobs that required me to be at work by 8 every morning. It also sucked when I was in grad school when everyone assumed people who weren't in their labs at the crack of dawn weren't properly dedicated grad students, even if we stayed later than everyone else in the evening (and where lab meetings were inevitably scheduled for 8 AM). It still sucks when I get an early morning class to teach, or when I want to enter a dog agility trial (they never start later than 8AM). Six AM feels like the middle of the night to me. Always has. Heck, these days, 9 AM feels like the wee hours.
I've been lucky over the past year or so. My teaching assignments have been afternoon and evening classes. This means I can do my writing until I get tired, go to bed (often between 2-3), wake up when I'm not tired anymore (instead of when my alarm tells me to), and still have some time in the late morning/early afternoon to grade, write lectures and answer student e-mails.
There is a down side, however. The older I've gotten, the fewer people I know who are night owls. Most of my friends want to engage in social activities that start (horrors) before noon. And not a week goes by where someone doesn't conspire to rob me of my sleep. Appointments and meetings with colleagues usually involve penciling out a block of time in the morning. And there are those mid-morning phone calls. Most people think it's entirely reasonable to call at 9:30 AM, even on weekends. My sleepy hello earns me a bemused, "Did I wake you up?" (asked in a vaguely disapproving voice). Most people are flabbergasted when I tell them how late I go to bed. I remember one time when a friend told me she thought my computer clock must be broken. When I asked why, she said, "The time stamp on your last e-mail read 2 AM. There's no way you'd be up that late ... would you?"
At a certain level it's silly for me to feel guilty or apologetic for being a night owl. It seems to just be how I am, and I know I'm not completely alone. But people like me are a distinct minority, and it always feels bad to be outnumbered.
And getting up early has traditionally been linked with industriousness, while sleeping in has been associated with sloth and indolence. I saw a link to a study that insists that morning people are happier than night people (wonder if being able to work and play on a schedule that works for you influences happiness). But I also saw one to a study that suggested that night people are more intelligent, if less cooperative (wonder if uncooperative is defined as refusing to get out of bed when nagged).
In my experience, night people are usually perfectly happy to let their morning-oriented friends and family members go to bed when they're tired and wake up when they're rested (I actually kind of like having the house to myself late at night), while morning people tend to want to get night people on their schedule.
It's a bit lonely being a late night person, but it's been a part of who I am for so long I can't imagine being anything else.