Better Than Before: What I Learned About Making and Breaking Habits--to Sleep More, Quit Sugar, Procrastinate Less, and Generally Build a Happier Life

by Gretchen Rubin

I’m a Lark: I go to sleep and wake on the early side. Owls do just the opposite. I used to believe that Owls could become Larks if they made an effort to go to sleep earlier, but research suggests that this attribute is hardwired. Genes play a big role, as does age: young children tend to be Larkish; adolescents tend to be Owls (with a peak at age 19.5 for women and age 21 for men); older adults tend to be Larks.