Our society seems to celebrate the ambition of early risers. We tend to admire the person who’s out on a seven mile jog at the crack of dawn or the employee who’s firmly planted at their desk long before everyone else arrives.
The night owl, who sleeps through most of the morning, is viewed as lazy or irresponsible at best, drunks or criminals at worst.
Do we have it all wrong? Evolutionary psychologist Satoshi Kanazawa poses that question in the latest entry in his blog The Scientific Fundamentalist.
He hypothesized the most intelligent American children grow up to sleep in later their peers. The author looked at the possible relationship between early childhood IQ scores and reported bedtimes in early adulthood.
Kanazawa classified children into five categories according to their IQ scores. Children with IQ less than 75 were considered very dull, above 125 were called very bright. Those in the middle of the bell curve, with a score around 100 were considered average.
You can see in the charts below, the higher the childhood IQ scores the more likely the subjects were to stay up later in early adulthood.
While the data suggests the smartest people turn out to be night owls and the least intelligent end up as larks, there might be more to this relationship than the author lets on. In his entry he fails to define early adulthood. If this includes people around the ages of 18-25 there may be some lifestyle factors at play.
College students are notorious for their nocturnal tendencies. Most Americans of above average intelligence pursue some form of higher education. Many of the most gifted go on to get Master’s degrees or PhD’s, extending that lifestyle by 2-6 years.
Those that choose to go straight into the workforce after high school don’t have the luxury of making their own schedule and sleeping in like college students. They jump right into working the typical 8-5, or even early bird hours, in the case of some blue collar jobs like manufacturing.
Regardless of if the hypothesis is true both chronotypes still come with downsides. Evening-types have a higher risk of severe depression symptoms. Larks may never reach a level of maximum performance during the day.
Contrary to traditional wisdom, morning types were found to be no healthier, wealthier, or wiser than night owls.
It’s best to follow your instincts when it comes to your sleep schedule. Trying to switch from night owl to lark may end up cutting into length of sleep, ultimately doing more harm than good.