Совы и жаворонки: кто есть кто?

Person who tends to stay awake at night

A night owl, evening person or simply owl, is a person who tends or prefers to be active late at night and into the early morning, and to sleep and wake up later than is considered normal; night owls often work or engage in recreational activities late into the night (in some cases, until around dawn), and sleep until relatively late in the day. The opposite of a night owl is an early bird – a lark as opposed to an owl – which is someone who tends to begin sleeping at a time that is considered early and also wakes early. Researchers traditionally use the terms morningness and eveningness for the two chronotypes or diurnality and nocturnality in animal behavior. In several countries, especially in Scandinavia, one who stays up late is called a B person, in contrast to an early riser being called an A person.

While staying up after dark was considered a negative trait, this changed in 17th and 18th century Europe (and subsequently spread beyond) due to the development and implementation of artificial lighting: more domestic lights, added street lighting, and adaptation by the royal and upper social classes. The introduction of chocolate, coffee and tea, and cafes that stayed open through dawn, became part of the new culture. Most owls sleep during the day and hunt for food at night.

Usually, people who are night owls stay awake past midnight, and extreme night owls may stay awake until just before or even after dawn. Some night owls have a preference or habit for staying up late, or stay up to work the night shift. Night owls who work the day shift often have difficulties adapting to standard daytime working hours. Night owls have often been blamed for unpunctuality or attitude problems. Employers, however, have begun to learn to increase productivity by respecting body clocks through flexible working hours, while the Danish "B Society" of night owls However, they lag behind larks in academic performance, and they tend to have unhealthier eating habits, as well as higher rates of smoking. Some night owls who have great difficulty adopting normal sleeping and waking times may have delayed sleep phase disorder. Morning light therapy may help to shift sleep rhythms for the night owl.

The night owl pattern is more prevalent in men than in women. Night owls are more likely to be single than in long term relationships.

A 2007 survey of over 55,000 people found that chronotypes tend to follow a normal distribution, with extreme morning and evening types on the far ends.