Questionnaire results from more than 350 people showed that morning types are attracted to concrete information rather than abstract thinking and like to rely on logic rather than intuition. They tend to be introverted, self-controlled, and eager to make a good impression on others. In contrast, evening types have a far more creative outlook on life, are more prepared to take risks, are more independent and nonconforming, and are a little impulsive. (more; HT Katja Grace; see also)
Larks are older, more conformist, more dependable [than owls], and so more likely to set official rules. Such rules seem to favor lark-preferred hours of work, school, etc., and to give larks higher school grades even though owls are smarter and eventually richer. (more)
So some folks really do lean far, while others lean near. Near folks coordinate better to benefit their kind. Which makes sense – in contests of conniving, practical minded folks should consistently beat idealists.
Note that although in general happy is far, larks are happier.
I am definitely a lark. (Writing this at 4:30 AM, and for me, that comes at the beginning of the day, not the end.) When you reach the point of having a 9:00 PM, or earlier, bedtime, you're definitely in the range where such habits seem quite eccentric in a thirty-year-old man.
And this fits pretty well. I am mostly oriented towards the Near kind of thinking and values, and towards an almost bee-like devotion to whatever my current set of habits happen to be. But at the same time, I also identify with the Owls who will stay up late, party, and think creatively; I can be like them, and such friendships as I form are likely to be with them. So yeah, I have owl tendencies, but the lark in me usually wins.
That's interesting stuff.
I used to be an owl, but as I grow older I find myself becoming more and more of a morning person.
I guess that conforms with your research.