Authors:

It's uncommon, but there are some people who just have a delayed circadian rhythm and they just - they sleep better during the day then they do at night. So they've - a lot of those people with delayed sleep phase disorder they start to work in bars, they work some of the late night shifts, they sort of adjust to doing it more and more as time goes on.

Big Think Interview, bigthink.com.
It's uncommon, but there are some people who just have a delayed circadian rhythm and they just - they sleep better during the day then they do at night. So they've - a lot of those people with delayed sleep phase