Scientists Describe Internal Clocks That Don't Follow Day and Night Cycles

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Scientists Describe Internal Clocks That Don't Follow Day and Night Cycles

Posted by samzenpus on Thursday September 26, 2013 @04:37PM from the up-all-night dept.

sciencehabit writes "Almost all organisms, from bacteria to mammals, have a circadian clock—a mechanism in their cells which keeps them in sync with Earth's day-and-night cycle. But many organisms follow other rhythms as well. Now, new research provides the first evidence that animals have molecular cycles independent of the circadian rhythm. They include a sea louse whose swimming patterns sync up with the tides, and a marine worm that matures and spawns in concert with the phases of the moon. The discoveries suggest that noncircadian clocks might be common and could explain a variety of biological rhythms."

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Lunar clocks? by ozmanjusri · 2013-09-26 16:52 · Score: 5, Interesting

I wonder if they realise a significant proportion of humanity have internal clocks based on a lunar cycle?

--
"I've got more toys than Teruhisa Kitahara."
1. Re:Lunar clocks? by Narcocide · 2013-09-26 16:55 · Score: 5, Funny
  
  My internal clock is based on a caffeine cycle.
2. Re:Lunar clocks? by snowraver1 · 2013-09-26 16:55 · Score: 1
  
  Warewolfs
  
  --
  Copyright 2010. All rights reserved. This comment may not be copied in any way including, but not limited to caching.
3. Re:Lunar clocks? by Maxo-Texas · 2013-09-26 17:21 · Score: 2
  
  After I retired, it became clear my "natural" cycle was about 26 hours.
  Annoying!
  
  --
  She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
4. Re:Lunar clocks? by Anonymous Coward · 2013-09-26 17:30 · Score: 2, Interesting
  
  Well, "lunacy" is definitely a thing. People freaking out during full moons has happened since the dawn of man.
5. Re:Lunar clocks? by jdbuz · 2013-09-26 17:33 · Score: 2
  
  Nope. Well, not unless you're really into surfing. But all that nonsense about hospital rooms visits and the like syncing with lunar cycles has been debunked time and time again. For example: Bad Astronomy Science Daily
6. Re:Lunar clocks? by captainpanic · 2013-09-26 17:35 · Score: 3, Informative
  
  I think that the female cycle is close to the lunar cycle, but not exactly synchronized with it. It would be similar to people having a 22 hour day cycle instead of 24.
  The menstrual cycle can be anywhere from 25-35 days, with an average of 28 days.
  The lunar cycle is 29.5 days.
  On a sidenote, imagine the horror if all women of the world would have their period exactly synchronized!
  http://en.wikipedia.org/wiki/Menstrual_cycle
  http://en.wikipedia.org/wiki/Lunar_phase#Overview
7. Re:Lunar clocks? by lennier · 2013-09-26 17:48 · Score: 5, Funny
  
  Warewolfs
  If bitten you have an irresistable urge to download cracked pirate copies of the latest games? Or just want to hang around large empty buildings filled with shipping goods in transit?
  The wearwolf, now that's far a more dangerous beast; it haunts the catwalks of Paris and Milan, possessed of an insatiable hunger and a suit with more dimensions than the eye can follow without watering.
  
  --
  You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
8. Re:Lunar clocks? by Anonymous Coward · 2013-09-26 17:53 · Score: 2, Interesting
  
  It's even more annoying whilst in the midst of your career like I am. I have noticed I definitely do not operate on a 24 hour clock either and it is hell. Fortunately for me I telecommute. A few weeks ago I was going to bed at 4pm while waking up around 2am, and day after day it kept getting progressively later until I made my way all around the clock again. For the past few days I've been taking two 4~ hour naps. One around 3pm and one around 3am.
9. Re:Lunar clocks? by formfeed · 2013-09-26 18:05 · Score: 5, Funny
  
  You forgot about the wherewolf. The poor thing gets constantly lost.
10. Re:Lunar clocks? by Thanshin · 2013-09-26 18:06 · Score: 2
  
  My manic/depressive system works on a weekly cycle. Except when I'm on holidays.
11. Re:Lunar clocks? by Cryacin · 2013-09-26 18:08 · Score: 2
  
  There are many out there whose clocks are based upon how often windows needs a restart.
  
  --
  Science advances one funeral at a time- Max Planck
12. Re:Lunar clocks? by gigaherz · 2013-09-26 18:10 · Score: 4, Interesting
  
  Sleeping after lunch works well for a lot of people. I'm Spanish -- we know about our 'siesta'.
  There's evidence that we naturally used to sleep in two phases, and some people have suggested a similar pattern to yours.
13. Re:Lunar clocks? by gigaherz · 2013-09-26 18:14 · Score: 1
  
  Then we'd have "mating seasons", like many other animals. Maybe the reason they are NOT synchronized is because it was too much of a distraction...
14. Re:Lunar clocks? by OptimalCynic · 2013-09-26 18:57 · Score: 1
  
  If you're talking about menstruation, it's a myth that it's linked to the moon.
15. Re:Lunar clocks? by epine · 2013-09-26 19:14 · Score: 2
  
  On a sidenote, imagine the horror if all women of the world would have their period exactly synchronized!
  From what I've been reading lately—in recent books—about half of the crabbiness is due to women not eating enough to compensate for their increased metabolic rate during their periods. Men also get crabby when we don't eat enough to replenish our willpower reserves. It takes willpower to make the generous response rather than the first lizard response that enters our brain.
16. Re:Lunar clocks? by ozmanjusri · 2013-09-26 19:46 · Score: 3, Funny
  
  That could explain a lot about both Parkinson's and Tourette's...
  
  --
  "I've got more toys than Teruhisa Kitahara."
17. Re:Lunar clocks? by wvmarle · 2013-09-26 20:01 · Score: 1
  
  Conclusion is a bit odd. As if it'd be a surprise.
  First that comes to mind is indeed the human female menstual cycle.
  Another is the yearly breeding cycle in most other animals, where they follow some yearly cycle (though that may not be a biological clock indeed).
  I also wonder how animals that live their life underground, or in the deep sea (no sunlight) do. Do they also have a "day" rhythm, for example?
18. Re:Lunar clocks? by wvmarle · 2013-09-26 20:03 · Score: 1
  
  Animals that have a mating season, usually have no sex drive outside that season (that accounts for males and females).
  Big difference with humans and certain other primates, where both sexes are always interested in sex.
19. Re:Lunar clocks? by umbrellasd · 2013-09-26 20:57 · Score: 1
  
  If "they" are men, they know very well that half of humanity is running on a lunar cycle...
20. Re:Lunar clocks? by Anonymous Coward · 2013-09-26 21:06 · Score: 1
  
  No one modded you up because no one believes someone who posts on /. is privy to such facts. And we're all too afraid to Google it.
21. Re:Lunar clocks? by TapeCutter · 2013-09-26 22:01 · Score: 4, Interesting
  
  A quick check of WP says that the largest meta-study found no correlation, they found what they claimed to be "statistical errors" in the 20 studies that did find a correlation. To me that doesn't say "no", it says the evidence we have to date is weak (unless there's a much larger set of "error free" papers backing the "no correlation" side).
  
  Personally I think there is a grain of truth in it, and my ex-wide who worked in ER for several years (as a cleaner) swears by it. However the moon doesn't actually create freaks from otherwise normal people, rather it provides just enough light for existing freaks to wander about at night and hurt themselves/others. I wouldn't expect the effect to be noticeable in a modern city hospital because city lights outshine the moon anyway. Weather also plays a huge role in the number of freaks wandering around at night, like everyone else, they (mostly) have enough sense to get out of the rain and are much more active on warm nights than cold. According to my ex-wife and her co-workers, a full moon on a hot and humid Saturday night is the perfect freak storm in a rural (or beachside) ER, statistically you're more likely to be murdered on a hot humid day than any other day.
  
  There's a very good reason that virtually every ancient religion has a sun and/or a moon god, they were observed to rule the natural cycles around them. Modern city/urban life obscures most of those observations and people are left wondering why the hell stone age people went to the effort of building places like stone henge.
  
  I think it's pretty much the same reason our modern society went to the effort of building the LHC or the Hubble telescope, ultimately they were trying to understand the world around them. Knowing where and when to turn up for an "all you can eat" buffet is a very deep behaviour in evolutionary terms, creatures as diverse as apes, jellyfish, corals, bears, and crocodiles make good use of it.
  
  In most cases we are at a complete loss when it comes to explaining these things in detail. For example, how do crocodiles "know" to gather an hour or so before fish become trapped on a flooded river ford? - The brief event (filmed by Attenborough) only happens right at the peak of a king tide. AFAIK, nobody (including Attenborough) has a clue how the hell the crocs tell the difference between a high tide and a king tide BEFORE it arrives. In ancient times people just accepted that (say) the crocs inexplicable ability to predict king tides was due to "divine knowledge".
  
  Humans are the undisputed masters of observing and exploiting patterns, however the root cause of the pattern is often irrelevant to it's utility. Ancient people would have simply observed the crocs (a wise defence behaviour anyway) and been alerted to the imminent fish bounty by their behaviour, some would have been mauled/taken by crocs when they went after the fish, lucky escape stories would abound, semi-random rituals would rapidly emerge to appease and thank the crocs. Next thing you know everybody wants a row of granite crocodile gods adorning their pyramid's driveway, and virgins are feeling nervous.
  
  --
  And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
22. Re:Lunar clocks? by PattyMc · 2013-09-26 23:16 · Score: 1
  
  I have kept charts on my sleep schedule for years being as there is absolutely no circadian rhythm to it at all. There is no pattern, at least not that I can find. When I was in school and working I had to be up in the morning despite only having a few hours - or none - of sleep. Now that I am retired the whole day/night thing has just disappeared completely. Sometimes I won't sleep for 30 hours, sometimes 2, sometimes 12. I have read several books on sleep and took one of those TTC courses on it but have yet to encounter any mention of individuals having no pattern at all although I am sure there must be other people out there experiencing the same thing. My Mom was sorta the same way and as my sister gets older, it is becoming more pronounced in her as well. My Dad and brother were totally regular 8 hours a night people. I think there is way more variation in sleep needs/patterns than we suspect.
23. Re:Lunar clocks? by ciderbrew · 2013-09-26 23:21 · Score: 5, Funny
  
  I keep falling off my beer cycle.
24. Re:Lunar clocks? by parkinglot777 · 2013-09-26 23:50 · Score: 1
  
  If I understand correctly about the definition of circadian rhythm -- http://en.wikipedia.org/wiki/Circadian_rhythm -- it does not relate to what you are talking about here. If you are talking about an article at University of California -- http://www.ucop.edu/sciencetoday/article/18885 -- then I may be related but I still believe that it is a bit off topic.
25. Re:Lunar clocks? by quarterbuck · 2013-09-27 00:04 · Score: 1
  
  That is not true, women's cycle is disrupted by lack of light etc. Women living underground without sunlight mess up their sleep cycle and their menstrual cycle. Then there is the fact that the timing can be broken by events on earth (http://en.wikipedia.org/wiki/McClintock_effect) rather than in the moon.
  It seems like women's body count 1-28 circadian cycles to form a pseudo-lunar cycle, rather than it being on an independent cycle.
  
  --
  http://slashdot.org/submission/1062723/Cheap-mobile-data-plan?art_pos=2
26. Re:Lunar clocks? by sjames · 2013-09-27 00:48 · Score: 1
  
  There wolf! There castle.
27. Re:Lunar clocks? by TheSkepticalOptimist · 2013-09-27 01:11 · Score: 1
  
  Unfortunately one could suggest that sleeping after lunch doesn't do much to improve the economy of a country.
  
  --
  I haven't thought of anything clever to put here, but then again most of you haven't either.
28. Re:Lunar clocks? by dywolf · 2013-09-27 01:16 · Score: 1
  
  Be like The Purge (decent flick), but worse...and more often.
  Actually that'd be a great b or c movie.
  Every 29 days men and children would lock themselves in bunkers while chaos and monsters roam the streets....
  
  --
  The guy who said the election was rigged won the presidency with the second-most votes.
29. Re:Lunar clocks? by Bigbutt · 2013-09-27 01:33 · Score: 1
  
  ...both sexes are always interested in sex.
  Until marriage.
  [John]
  
  --
  Shit better not happen!
30. Re:Lunar clocks? by AJH16 · 2013-09-27 01:36 · Score: 1
  
  What about the airwolf?
  
  --
  AJ Henderson
31. Re:Lunar clocks? by Maxo-Texas · 2013-09-27 03:11 · Score: 1
  
  Well...
  If everyone slept, then pay would be slightly less but things would cost less.
  Or you might be able to have higher employment.
  Seriously -- we don't have to run our economy at breakneck speed all the time. It wasn't anything like this back in the 80s when I started working.
  
  --
  She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
32. Re:Lunar clocks? by terjeber · 2013-09-27 03:31 · Score: 1
  
  There is only one type of person,that would consider this as news. A male scientist who's never lived with, dated nor talked to a girl, woman,or any other kind of entity of the female persuasion.
33. Re:Lunar clocks? by Overzeetop · 2013-09-27 03:49 · Score: 1
  
  Actually, I believe MOST people have a sun-independent rhythm of 24.5-27 hours. When placed in isolation from normal sunrise/sunset, nearly everyone drifts to a longer wake cycle resulting in an extended "day". I can't remember the specific paper I read.
  
  --
  Is it just my observation, or are there way too many stupid people in the world?
34. Re:Lunar clocks? by cusco · 2013-09-27 04:16 · Score: 1
  
  It can be. I knew several practicing Wiccans who nightly observed the the moon phases (well, as 'nightly' as one can get in Seattle). After a couple of months their cycles somehow got synched to around the time of the full moon, and stayed that way until I moved out of town and lost contact with them a year or so later. None were on any artificial birth control and all were vegetarians or almost-vegetarians who cooked almost everything at home. A couple of them lived in the same house for a time (women living together will sometime synchronize their cycles), but the rest never did.
  
  --
  "Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
35. Re:Lunar clocks? by Muad'Dave · 2013-09-27 06:12 · Score: 1
  
  We must all be from Mars, then - a 24.67 earth-hour day.
  
  --
  Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
36. Re:Lunar clocks? by kwbauer · 2013-09-27 07:08 · Score: 1
  
  Yup, the countries that traditionally have the afternoon siesta and the countries that mandate by law long vacations have such awesomely low unemployment rates... As always, never let current facts get in the way of a good argument.
37. Re:Lunar clocks? by HornWumpus · 2013-09-27 16:03 · Score: 1
  
  Why this is actually news to nerds.
  
  --
  John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
38. Re:Lunar clocks? by HornWumpus · 2013-09-27 16:08 · Score: 1
  
  Still interested. Just not with each other.
  
  --
  John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
39. Re:Lunar clocks? by HornWumpus · 2013-09-27 16:12 · Score: 1
  
  Props to dice.com. This is actually 'News for Nerds'.
  
  --
  John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
I don't put much into these cycles.. by Anonymous Coward · 2013-09-26 17:00 · Score: 1

Life on a submarine is an 18 hour day for months at a time. No sun, days, nights, weekends, not even the meals are in sync with the typical 12+6 work/sleep schedule. One cycle you wake up to dinner, the next time it's lunch, and then breakfast and so on. I don't know too many people that freaked out because of the strange schedule. Some faked or actually committed suicide but it was usually because of a wife/girlfriend.
Isn't the natural period of human clocks 27 hrs? by tlhIngan · 2013-09-26 17:26 · Score: 2

ISTR that the period of the human body clock is not 24 hours, but 27.
That is, if you remove the cues of time from someone, their natural sleep/wake cycle would rapidly approach 27 hours.
Something about it being based on a relaxation oscillator which means the day/night rotation of the earth actually resets it constantly...
Re:Isn't the natural period of human clocks 27 hrs by jdbuz · 2013-09-26 17:40 · Score: 2

Everyone's different. Some go longer some shorter. There's been a few deep studies on this but I think the most accessible description I've found is in the book Sync by Steven Strogatz
Different for me... by fahrbot-bot · 2013-09-26 18:09 · Score: 4, Interesting

My biological clock seems to run around a 26-30 hour cycle, which often makes it difficult for me to maintain "normal" work hours. Trying to go to sleep early is often fruitless so, eventually, I simply stay up all night and drag myself through the next day and then go to bed at an appropriate time to force reset my cycle. I've been this way for as long as I can remember - and I'm now 50. On the up side, I can (still) work productively for 36+ hours straight - I'm a senior mostly-Unix-ish system programmer/administrator btw.

--
It must have been something you assimilated. . . .
1. Re:Different for me... by wonkey_monkey · 2013-09-26 19:11 · Score: 5, Funny
  
  and I'm now 50.
  On the plus side, that's only 43 in "you" years.
  
  --
  systemd is Roko's Basilisk.
2. Re:Different for me... by Godwin+O'Hitler · 2013-09-26 21:42 · Score: 1
  
  During a few weeks in my life when I had nothing going on, no job, no commitments, I just went to bed when I felt tired – or rather when I'd had enough of that particular day – with no regard for the clock.
  Over the space of a week, my living day had shifted by a full 12 hours. I found that quite amusing.
  
  --
  No, your children are not the special ones. Nor are your pets.
3. Re:Different for me... by 0111+1110 · 2013-09-27 07:38 · Score: 2
  
  You've had this non-24 condition since birth? That's tough. I can't imagine having that problem as a kid while in school. Damn. It only started for me after a head injury, but now my normal cycle is also around 25-27 hours. It does make it extremely difficult to lead a normal life.
  I assume you've tried everything, but have you tried Dark Therapy? No artificial lighting after dark? It's kind of tough for me because it means I can't use a computer or read. I've sometimes listened to audio books though and a really boring audio book can be helpful for putting you to sleep as well.
  There are some theories that it is only necessary to eliminate the shorter wavelengths of light and that amber to red light is okay, but I think this is false based on my own experience and based on mouse studies where you have to get above 700nm for circadian rhythms to be unaffected and it's pretty hard to see that near infrared and only LED lighting could be that precise. One of these days I do plan to buy some 710-740 nm LEDs and test out whether I can read with them and whether it helps the non-24.
  
  --
  Quite an experience to live in fear, isn't it? That's what it is to be a slave.
The most important cycle of all by stox · 2013-09-26 18:32 · Score: 4, Funny

The paycheck cycle.

--
"To those who are overly cautious, everything is impossible. "
My clock is psychotic by jtownatpunk.net · 2013-09-26 20:23 · Score: 1

I haven't worked in over two years so, when I don't have to be synced with other people, I go to sleep when I get tired and get up when I'm done sleeping. When I get going on an interesting project, I might chug away for 30+ hours straight then sleep for 10-12 hours. Or I'll get in a cycle where I'm down for 3-4, up for 10-12. When I'm just chugging along, I'm usually up for 18-20 hours and sleep for 8-9 hours and I chase that around the solar cycle. Being able to go for months without setting an alarm and having electric lights and a DVR really let me step out of the traditional daily rhythm.
Tho I expect that I'll be negated by my current nomadic phase where I'm wandering around looking for a new place to settle down. If I want to explore a community, I can't really do that at 3am on a Thursday.
News from 11 B.C. by drainbramage · 2013-09-27 01:01 · Score: 1

More valuable research?
I hope no scientists were harmed in these experiments.
Was this from another of those fine 'scientific' journals?
If you think it was, good luck with 6th grade.

--
No brain, no pain.
Useful, but not the first to test it by lubaciousd · 2013-09-27 01:21 · Score: 1

From TFA:"Two papers published today present the first evidence for clocks independent of the circadian one:"

Plenty of people have been doing non-circadian clock work for years; I briefly worked in such a lab that had been investigating food- and sex-based timing mechanisms, but the non-circadian clock idea is at least as old as the seventies.[1][2]

[1] http://www.sciencemag.org/content/197/4301/398?ijkey=759219d8ce9c087620c8d8237098ff5956eeb489&keytype2=tf_ipsecsha
[2] http://jbr.sagepub.com/content/17/4/284?ijkey=4a9dd94e238a2aa60198739e7ea26d75ecdd3b5c&keytype2=tf_ipsecsha
1. Re:Useful, but not the first to test it by osu-neko · 2013-09-27 02:44 · Score: 1
  
  Yeah unfortunately the summary is pretty bad (welcome to /.). It's obviously well known that there are non-circadian clocks in many plants and animals. When they say this is "first evidence for [the] clocks", they don't mean first evidence for their existence, but rather for a particular mechanism.
  
  --
  "Convictions are more dangerous enemies of truth than lies."
2. Re:Useful, but not the first to test it by lubaciousd · 2013-09-27 03:52 · Score: 2
  
  Check out Dr. Takahashi's work at UT-Austin; a good one behind a paywall is Temperature as a Universal Resetting Cue for Mammalian Circadian Oscillators. Among other things, his group has investigated a variety of timing-dependent tissues(liver cells, neurons, stomach cells) and whether or not temperature could serve as a temporal resetting cue(the answer in many cases is yes).