Night owls vs morning larks: Is the 9–5 outdated?

Written by Beth Gault Wednesday 22 March 2023
Flexible working has evolved greatly over the past three years. But beyond remote, hybrid, or even compressed hours, what if there was a better way to structure the working day – based on employees’ own body clocks?
Brain on a split day and night background

The Centre for Applied Chronobiology (CAC) researches circadian rhythms – that is, our patterns of sleep-awake rhythms. Everyone is born with an internal biological clock, according to the CAC. Variations of genes called “chronotypes” cause a natural inclination to sleep or be awake at a certain time of day.

Professor of neuroscience and psychology at the University of California, Matthew Walker, suggests in his book Why We Sleep that 30% of the population prefers to wake up and go to bed later in the day, and 40% will happily wake up and fall asleep earlier. “Night owls are not owls by choice,” he says. “They are bound to a delayed schedule by unavoidable DNA hardwiring. It is not their conscious fault, but rather their genetic fate.”

The CAC says that a person who goes to bed early and gets up early is typically called an “A-person”, and one who goes to bed late and gets up late is a “B-person”. However, there is a curve of chronotypes, with around seven different variations within those patterns.

Are you a night owl, early bird, bear or dolphin?

According to the Sleep Foundation, people are largely split into four different types:

  • Also called the “wolves”, night owls make up about 15% of the population and, with their late sleep-wake schedule, are most productive in the evenings/at night. 
  • Early birds, also called “larks” or “lions”, are morning people with an early sleep-wake schedule who focus best before lunchtime. They make up around 15% of the population.
  • Over half the population are “bears” – following the solar cycle and not experiencing many problems with the traditional 9–5 schedule. Their ideal focus time is before 2pm, losing steam post-lunch.
  • Approximately 10% of us are “dolphins”, those who have problems sleeping. Peak productivity for this group is reportedly late morning.

Keep reading to learn what all this means for businesses


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