A new study suggests that students who stay up late in the night tend to display anti-social personality traits.

The researchers found that late nights encouraged mate poaching, casual sex, and risk-taking to which the dark triad traits are linked.
“Those who score highly on the dark triad traits are, like many other predators, creatures of the night. There is likely to be a co-evolutionary arms race between cheaters and those who wish to detect and punish them, and the dark triad traits may represent specialized adaptations to avoid detection”, lead researcher Dr Peter Jonason said.
Source-Medindia