Generally, taking a crap involves some level of pain.
I favour a third explanation: that menstrual cramping may have been a selective factor in the past, but since the advent of agriculture has been reduced to a vestigial feature. Back when our ancestors spent nearly the entirety of their time hunting, gathering food, evading predators, etc. there was little or no time left over for recreational activity such as fruitless sex. Couples who spent their time having unproductive sex when they ought to have been finding food had less of a chance of producing children and therefore passing on their genes. However, once agriculture was established, people were no longer living hand-to-mouth, and more food could be produced than was necessary to sustain the population. This allowed us to devote more time to recreation and technological development without compromising the survival of genetic material. Tens of thousands of years ago, menstrual cramps may have been much more prevalent in the general population than they are today, and as they no longer play a role in our evolutionary survival, they are becoming degenerate and less pronounced.
Because it never became vestigial. The appendix still serves several useful functions. That’s why it still exists despite incapacitating and even killing carriers.
No, it presupposes that food gathering, caring for children and avoidance of predators increased the odds of successful reproduction, nothing more, nothing less. To suggest that this isn’t true is a bit far fetched isn’t it?
No I’m not, I never said or implied any such thing. I referred to the chimpanzee branch of the ape family, which includes chimps, bonobo, australopithecines and various Homo species. At no stage and in no way did I ever state or imply that humans are descended from chimps.
You have failed to comprehend what I quite clearly posted.
[quote]
If a mechanism serves a useful purpose even only some of the time, then it’s a good bet it’s going to get passed on to subsequent generations.
[quote]
True, and if it the useful purpose is inefficiently performed and outweighed by the incapacitation of the individual it won’t be passed on. Since pain could only possibly have the benefit of delaying (and never actually preventing) STD transmission it seems a little improbable that incapacitating period pain would ever compensate for the risk at which it places the carrier. Mild period pain or psychic irritability I just might believe but incapacitation just doesn’t make sense on so many levels.
Theonly problem is that hunter-gatherers spend less time obtaining food than do agriculturalists. They have far more leisure time thn agriculturalists and as such more time for pointless copulation.
Added to this 1 hour/day spent in the act of copulation wouldnever place an individual at more risk than 3-10 days of incapacitting pain.
Added to this period pain stops during prgancy and breastfeeding, which woul have been the normal state of thes ehunter-gatherer wouldn’t it? So the mechanism would fail the vast majority of the time.
However, you haven’t explained how it could serve as a selective factor. Fruitless sex only results in no offspring; it doesn’t result in better- or worse-adapted offspring, or an increased (or even a decreased) possibility of having offspring. Whether the menstrual cramps are present or not, the effect is the same: no offspring during menstruation. As such, they cannot serve any selective function beyond possibly weeding out those females with low pain thresholds (in that those who were severely affected were more likely to be eaten by a sabretooth or some such). But then, that would be true of just about any pain.
[quote}And are there any other normal bodily functions, besides childbirth, that are painful?[/quote]
Define normal? Physical exercise is often painful. Arthritis seems to be a normal bodily function and is painful. Passing kidney stones etc. The difference is that we consider most of these to be abnormal these days and avoid them through medicine and surgery. We tend to avoid that for childbirth in many cases.
www.msu.edu/course/prr/213/Russell,ch5.doc
As shown in figure 5.1, the hours per day spent by one of the groups in hunting and gathering activities were not great. The most obvious conclusion Sahlins made from the data was that the people did not have to work hard to survive. The average length of time each person spent per day collecting and preparing food was three to four hours.
http://www.webcom.com/wildcat/ac01.htm
Two famous explorers of the earlier nineteenth century made estimates of the same magnitude for the aborigines’ subsistence activities: two to four hours a day (Eyre, 1845, 2, pp. 252, 255; Grey, 1841, 2, pp. 26163). Slash-and-burn agriculture, incidentally, may be more labor-intensive: Conklin, for example, figures that 1,200 man hours per adult per year are given among the Hanunóo simply to agriculture (Conklin, 1957, p. 151: this figure excludes other food-connected activities, whereas the Australian data include time spent in the preparation of food as well as its acquisition). The Arnhem Landers’ punctuation of steady work with sustained idleness is also widely attested in Australia and beyond. In Lee’s paper he reported that productive members of !Kung Bushman camps spend two to three days per week in subsistence. We have heard similar comments in other papers at the symposium. Hadza women were said to work two hours per day on the average in gathering food, and one concludes from James Woodburn’s excellent film that Hadza men are much more preoccupied with games of chance than chances of game (Woodburn and Hudson, 1966).
http://www.lrainc.com/swtaboo/stalkers/em_pp.html
Gardner (1972, p. 414), in describing the Paliyans, a foraging people of India, has pointed out that, “In normal times Paliyan men and women spend a bare three to four hours a day obtaining food and evidence no anxiety whatsoever about its supply.” Single individuals are able to feed themselves easily, and married couples may not feed each other. …… similar impression is left by descriptions of other tropical hunter-gatherer societies. Lee & DeVore’s famous Man the Hunter is often summarized as showing that most calories come from gathering, not hunting, that most gathering is done by females, and that hunter-gatherers need spend only a relatively small part of their time in gathering.
Are there any figures on what proportion of the female population suffer from no menstrual pain ?
I could just as easily theorise that the women who have menstrual pain aren’t as healthy as those who don’t. There does seem to be studies being done that indicate environmental factors play a large role in menstrual pain severity, e.g food and cigarette smoke.
In some environments, perhaps, but I very much doubt that this was the case for some of the less hospitable biomes colonized by humans and their ancestors. Anyone can laze about in some tropical paradise, feeding off of fruit that falls from the trees, but sustaining oneself in an arctic, alpine, or even temperate climate requires considerably greater effort, especially in the winter. Perhaps intensity of menstrual pain correlates with geography…? I wonder if there is a significant difference between, say, the Polynesians and the Inuit.
There is the further point that practiced agriculturalists are usually guaranteed a steady and replenishable supply of food, whereas hunter-gatherers often are not, and so are at greater risk of starvation. Hence, over broad periods of time, the agriculturalists are more at liberty to engage in unreproductive sex than are hunter-gatherers.
As I and others have mentioned, the pain is not typically incapacitating, but rather discomforting. If it were literally incapacitating and as long in duration as you claim, surely today’s employed women would call in sick 10 days a month.
I admit this is a good argument against my theory, since the hunter-gatherers will presumably continue to have sex during the female’s pregnancy. One might speculate, though, that the female’s receptiveness to (purely recreational) sex for a continuous nine months is the couple’s “reward” for having successfully conceived in the first place. Maybe that’s stretching it, though.
This is actually HennaDancer, jumping in while Martin’s in the potty.
Ain’t nobody going to stop having sex, regardless of food supply. So long as orgasms are involved, humans are going to Do It.
Also, I’ve breastfed my two sons and in both cases started my period a scant two months after birth. For those of you not in the know, after you give birth, there’s a 4-6 week time during which you have all those periods you missed. Okay, it only seems like that. Anyway, you bleed for over a month. You are not fertile then. I have about 5 weeks of this, then a couple weeks off, then I’m starting back on my regular period. That’s completely breastfeeding, on demand. I don’t know for sure when my fertility starts back up again but I’m betting I could get knocked up almost as soon as the previous kid was out.
On the other hand, my friend didn’t start again until her kid was almost two but still nursing occasionally. Bitch.
My point in this is to say that nursing a child will not keep you from getting pregnant again.
HennaDancer
No, it appears to be universal. AT least I’ve never seen any evidence of a place where it isn’t true. It’s true of the !kung San of the Kalahari and of the far northern Eskimo, for the aboriginals of the Central Australian Deserts as well as the Malaysian rainforests. I can’t think of any more extreme biomes than those. It seems to be universal. In any environment hunter-gatherers spend less time obtaining food than do agriculturalists.
Which is also not true. Hunter gatherers suffer less from the effects of drought, famine and starvation than do agriculturalists. Far more pre-industrial agriculturalists died of starvation, both absolutely and in percentage terms, than did hunter-gatherers.
Women affected to that degree today use medicines, including oral contraceptives, to reduce the intensity, that’s why they don’t call in sick. Also 10 days is the extreme and I mostly associated with the unusual 60 day menstrual cycle.
Yes, but if recreational sex places individuals at reproductive risk sufficiently to warrant period pain then they would be just as likely to die during intercourse in pregnancy. In the case of the female moreso.
Yes I have, because time available for sex, which is not necessary for survival of the individual, is exactly equivalent to that time remaining after all more pressing needs are taken care of. In one month, any given individual in a primitive society will have to fulfill certain tasks, which may involve hunting, fishing, gathering food and materials for tools and weapons, construction of shelters from the weather, production of tools and weapons, and fending off predators. A certain amount of time is left over. Since some of the survival tasks can be delayed or time-shifted, it is of greatest benefit to the species as a whole (but not necessarily to the individual) to prefer performing the survival tasks during periods of infertility, leaving more time available for sex during periods of ovulation. One way of encouraging this behaviour is to make the female unreceptive to sex during menstruation, since ovulation is unlikely to be occurring at that time. A non-destructive way of accomplishing this might be to induce mild pain during menstruation, since the intensity would not prevent most women from performing their other duties.
About 20 hours/day then if the anthropologists figures are to be believed. Far more than the time avaialale to modern people or even pre-industrial people.
It hardly sems like time for copulation was ever an issue for humans before we invented agriculture. Maybe there were some small pockets where time was of concern, even after dark, but they must have been tiny and couldn’t really have spread any such genetic predisposition to most of the humans on the planet.
Basically it seems to be a good time to bring out the razor. It can simply be explained becuase menstruation wasn’t common in pre-industrial females and so it was never an issue. Or we can go with te more complex hypothesis that it served to allocate time.
Well, some anthropologist are convinced of something else: that painful childbirth is a product of the way human skeletons have evolved as we’ve walked upright (the pelvis must be a certain shape /size to support the body and the organs) and the fact that fetal heads have to be big to hold all the necessary grey matter. These two things aren’t all that compatible (according to this theory). It makes for a tight fit and requires a pretty complex serious of movements to get the baby down and out through the birth canal. It’s so tight that babies have to twist and turn and their skull bones get squeezed together during birth. Some women have their tailbones broken because of the fit. That is not a product of Victorian prudery.
It’s true that most woment do not exercise many important pelvic muscles (and that doing so might greatly improve some of the discomforts of labor), but the fact is that the cervix simply must be cranked open by the uterine cramps (and the pushing of the baby’s head) and that’s painful for some women. You can’t exercise the cervix.