Your faithful correspondent is not a morning person, so opening the Library at 8am was most definitely not a welcome experience.
But what makes us this way?
Internal Time: Chronotypes, Social Jet Lag, and Why You're So Tired. QP84.6 R6413 2012
"Early birds and night owls are born, not made. Sleep patterns may be the most obvious manifestation of the highly individualized biological clocks we inherit, but these clocks also regulate bodily functions from digestion to hormone levels to cognition. Living at odds with our internal timepieces, Till Roenneberg shows, can make us chronically sleep deprived and more likely to smoke, gain weight, feel depressed, fall ill, and fail geometry."
Turns out those who don't like mornings aren't just slackers and those who can't push through to midnight aren't just lame. They are made that way.
Rhythms of Life: The Biological Clocks that Control the Daily Lives of Every Living Thing. QP84.6 F67 2004b