RichA wrote:
On Friday, 26 June 2015 11:57:46 UTC-4, Chris.B wrote:
On Friday, 26 June 2015 16:55:02 UTC+2, Quadibloc wrote:
The following news item

http://www.sciencedaily.com/releases...0625145232.htm

concerns the KaiC protein, which encodes the 24 hour length of the day, thus
facilitating the circadian rhythm.

Unfortunately, they referred to the length of the day as "Earth's daily rotation
period", which will only serve to prolong the confusion exemplified by a
participant in this newsgroup.

John Savard

Research where participants are denied visual stimulus for daylight
hours often show very wayward timekeeping over extended periods.

Dare one suggest that the educationally-challenged miscreant, to whom
you may be referring, may actually be a cough caveman?

Tests done in the 40's showed that humans can't adapt to a non-24hour day
once they reach a certain age. Younger people are able to adapt to a different day length.

The 1940's - that was long before the effects of bright light on melatonin
was known. Free running humans not exposed to a day-night cycle tend to
synchronise at a longer day length than 24 hours. Synchronisation to a 24
hour day depends on daily exposure to bright light and can be changed just
by selectively altering the exposure to light. This is true even for blind
people.
As for older people I worked on call and shifts until I was over 50 and had
less trouble with changing day lengths than some younger people who had
less experience of this.
If you read Frederic Pohl's autobiography you will find that he
experimented with 48 hour days and was quite comfortable with this.