Researchers from the London School of Economics have found that people with high I.Q.s are more likely to be night owls, whereas folks with lower I.Q.s are more likely to wake up early and function their best during the day. Other studies have found a link between “eveningness” and getting good grades in school.

However, all is not well with those who burn the midnight oil. People who are disposed to staying up late are less reliable and more likely to suffer from depression and various addictions when compared to early risers.

Smart People Stay Up Late and Sleep Late – Asylum.com.