Since we humans don’t get around naturally very well during the dark hours, we tend to be diurnal creatures. There are a very few (1 in 10) that wake up before the alarm goes off, ready to start their day, even before day break. These “early chronotypes” have been termed “larks.”

“Larks are the mortal enemy of the 2 in 10 humans who lie at the other extreme of the sleep spectrum: ‘late chronotypes,” or owls. In general, owls report being most alert around 6 p.m., experiencing their most productive work times in the late evening.” They often stay up until the wee hours of the morning and it may take several cycles through the alarm for them to stir.  (John Medina, in Brain Rules)

Most of us, the remaining 70% are called “hummingbirds.”

A new study, reported by Psychology Today, shows that “more intelligent children grow up to be more nocturnal as adults than less intelligent children.”

I wonder how these categories impact my previous post on late night eating and weight gain. The study on mice showed that when they were fed during the day, being nocturnal creatures, they gained weight. It seems that if there are humans that are truly nocturnal, that they could eat during the night without the same negative effects that are experienced by the larks and hummingbirds.