It turns out that the representatives of the indigenous peoples of the North have a unique sleep biorhythm.
During the polar day they sleep 2-3 times a day in short intervals, and in winter, in the polar night, on the contrary, they can sleep more and deeply.
This "flexible sleep" is an evolutionary adaptation to extreme conditions. It helps you conserve energy, maintain concentration, and maintain a sense of time in a world where night and day change every six months.
This lifestyle is often found in arctic families: some go to sleep during the day, some at night, and some rest several times during the day. And at the same time they all work in harmony, following the natural cycle of the tundra.