Are You an Early Bird or a Night Owl?

Does the early bird always get the worm? Are there real biological differences between early risers and night owls? Ask Science explains.

Sabrina Stierwalt, PhD
4-minute read
Episode #131

Hi I’m Dr. Sabrina Stierwalt, the Ask Science, bringing you Quick and Dirty Tips to help you make sense of science.

As an astrophysicist, I am happiest when I am at a telescope observing distant galaxies. My happiness is not just because I’m gathering data to further my research, but also because my body and mind feel their best at night. But that's not the case for everyone. I know plenty of folks who functon best in the early morning.

Do we learn our sleep patterns or are they hard-wired in us from the start? Are there real biological differences between early risers and night owls? Let's find out.


Are Night Owls Born or Raised?

Scientists have long believed that our preferred sleep patterns (called our “chronotypes”) are genetically determined at birth. After all, it makes evolutionary sense for people to have varied sleep schedules. Someone needs to guard the cave at night!

I can also tell you from firsthand night owl experience that living with an early riser has made caring for our infant much easier. There is never a question of who should get up with her in the middle of the night versus the early morning. (Dibs on the night!)

Our preferences for early riser versus night owl behavior are encoded in genes called “clock” or “period” genes that regulate our circadian rhythms and are thus linked to our blood pressure, metabolism, body temperature, and hormone levels. Studies have shown links between the length of certain period genes and people’s chronotypes, as well as the amount of sleep they need per night.

Environmental cues like light and diet (called “zeitgebers”) can work to alter our body’s sleep clock. Anyone who has taken an overnight flight knows the groggy feeling of jet lag upon landing. Your body feels like it's 3am while the sunrise outside tells your brain something different. The glow of our tablets, smartphones, and televisions is enough to delay the body’s nightly release of melatonin, the brain’s message that it is time for sleep.  

Are Early Risers More Successful?

You have probably heard that the early bird gets the worm, but given that we are born with our chronotypes coded in, are early risers really more successful?

The hard truth is that the vast majority of us have responsibilities that do not allow us to sleep according to our body’s preferred schedule. Most work days start between 7 and 9am, but for night owls, waking this early can feel similar to the jet lag you experience after that overnight flight. The feeling is so similar, in fact, that it has been called “social jetlag.” So if you're an early riser, you tend to wake up without this social jetlag, which means you have a distinct advantage over night owls.

Our periods of alertness are linked to our bodies’ cortisol levels and cortisol peaks just after waking, most likely in anticipation of the day. However, early risers are already more alert in the morning than night owls, giving them an extra boost of potential for productivity. Feeling more alert and productive may be the reason early risers self-report as happier, healthier, more optimistic, and more proactive.

There are also links between being an early riser and getting better grades in school.

However, not all is lost for night owls......


Please note that archive episodes of this podcast may include references to Ask Science. Rights of Albert Einstein are used with permission of The Hebrew University of Jerusalem. Represented exclusively by Greenlight.

About the Author

Sabrina Stierwalt, PhD

Dr Sabrina Stierwalt earned a Ph.D. in Astronomy & Astrophysics from Cornell University and is now a Professor of Physics at Occidental College.