Lark (person)

According to Roenneberg, the distribution of circadian rhythms spans from the very early to the very late chronotypes, similarly to how height varies from short to tall.

Forced to arise earlier than their circadian rhythm dictates, they have a low body temperature and may require a few hours to feel really awake.

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.

[7] For instance, there is the case of the Per2 gene on chromosome 2, which was discovered in the early 1990s by Urs Albrecht and colleagues at the University of Fribourg in Switzerland.

Many employees in these industries start working at or before 7:00 a.m.[10] Some professions are well-known for their early morning hours, including bakers, school teachers, dairy farmers, and surgeons.

Morning larks may also work the early shift in round-the-clock industries, such as emergency services, transportation, healthcare, and manufacturing.