Synchrony of reproductive capacity would act to distribute male reproductive effort - forcing the male to choose, and thereby to commit, at least tribally. Synchrony of tribal reproductive effort abets tribal bonding, and organization of all efforts. Having moonlight for times of fertility takes advantage of male visual triggering to sequester otherwise disruptive efforts to spare time, night time - time when hunting and gathering cannot be done anyway. Just riffing. Point is, there are lots of possibilities.
Those are all plausible evolutionary reasons and perhaps are more, but I think we should look at the premise first. The paper was published 32 years ago. No one has replicated or further established a menstrual lunar synchrony. To start with, menstrual cycles vary from around 15 to 45 days with an average of 28.1 and a sigma of 3.95. On the other hand, the synodic month is 29.53 days long (sigma is zero), a rather significant difference. Other hypotheses for synchrony between proximate groups (e.g. McClintock's 1971 study of Wellesley students) have not been replicated. I think the current understanding is that there is little evidence for the phenomena, not with local/proximate groups and certainly not globally. And really, wouldn't we know if there was a lunar synchony? Shit would get crazy.
hunting by full moon would be a significant advantage. ... unless it was normal for a male to offer a dead animal as payment for sex. this would make a lot of sense as it would allow much more hunting time to ensure essential protien stores for gestation.
They are getting their data from people who live in artificial light regimes amid thousands of other people, and only occasionally see the moon. Note that the "natural" circadian rhythm in human beings is about an hour longer than 24 - it maintains synchrony by being reset, and people not subject to sunlight or other cues will go "around the clock" in their sleep/wake cycles. That is normal for such homeostatic circuits - balance via resisted tendency is often more reliable and easily maintained than delicately specified timing. That would depend on what it was. The value of synchrony might not depend, tribally, on which phase of the moon was which phase of the cycle - might easily vary by group. And by the time everybody's living in cities packed with transient stranger encounters or in isolated houses with nuclear families, there's no extracting that pattern. It's all speculative, but the research failures as described don't really indicate much one way or the other.
no one has yet mentioned the fact that women can consciousely change their menstral cycle and do soo all the time in large groups... this fact throws the entire study out the window of a fast moving car. great meme ! probably a study done by men to validate cuts in spending on reproductive health care for teenagers and low socio economic groups.
Actually in groups (as in offices) women change their menstrual cycle over time to match the dominant female. It's not conscious, but seems to be part of the herd physiology.
Although studies have not supported the theory of menstrual synchronization, nevertheless women themselves report having experienced this phenomenon quite frequently. It is believed by some to be a defense mechanism for a single female drawing attention from too many males. Synchronicity spreads the choices. https://en.wikipedia.org/wiki/Menstrual_synchrony It seems the matter is not quite settled yet. For many more citations, google........ menstrual synchronicity
I did google that and "menstrual synchrony dominant female". Nothing came up. That's why I asked for the cite.
Well, it is not much interest to me, but here is the site that cited a rather strange study which apparently produced the phenomenon. Read more: http://www.thegrindstone.com/2011/0...office-for-menstrual-synchrony/#ixzz5IQkWAUp8
I was thinking of the moon being the cause, agree not gravity Hard to do since it has no sweat pad Pheromones good call Problem - moon has a fixed cycle. From the cycle you can pick, roughly, 28 cycles ie from full moon to full moon, 1 day after full moon to 1 day after full moon. Work your way through the 28 days No sync - coincidence Please Register or Log in to view the hidden image!
pheromones and high-school erections maybe now, I understand why at the time I approached the blackboard in a math class holding a notebook in front of the erection embarrassed and In hopes that it would go unnoticed .................... it was good to be young once
Sure, the 1971 McClintock paper is the go to study that people cite. And as I mentioned in my first post, it has never been replicated. It's like Linus Pauling and vitamin C. Got a lot of traction back then and entered into the scientific mythos. Unfortunately, seems to be bunk. Like sine waves of varying frequency, women's cycles converge...and then diverge. It could be that varying cycles was the selective evolutionary pressure.
Well, I tend to believe the intelligent people who actually experience the phenomenon. This may be classified as anecdotal, but does not invalidate the observation.