Our circadian rhythm is synchronized with the 24-hour solar cycle by light signals received by non-rod, non-cone receptors found exclusively in our eyes. While the 70-80 percent of us who are dubbed hummingbirds manage this well, the “larks,” who tend to be up early, and late-rising “owls,” who turn in usually well after midnight, have difficulty resetting their internal clocks.
Larks, Owls and Hummingbirds - Olivia Judson Blog (via thisisareallybadidea)
I am clearly an owl. I find it nearly impossible to get to sleep before midnight, and pretty brutal to be up before 8am.
Source: thisisareallybadidea
