There are many types of circadian rhythms,
including daily fluctuations in body temperature, blood pressure, alertness, and melatonin.
I can't find a single person who will affirm that all the effects within a 24 hour day,
including massive temperature
fluctuations between day and night, is due to one rotation of the planet and that these days never, ever fall out of step with rotations.The ideology which contemporaries have inherited from the late 17th century is that the Earth's rotation falls out of step with 24 hour days to the tune of 4 extra rotations in 4 years by virtue of an utterly stupid idea that the planet's
daily and orbital motions can be modeled directly from a rotating celestial sphere of Ra / Dec observing.