PMS Evolved to End Bad Relationships, Says Scientist

[Kargathia]

Interesting, the presumption that evolution directs itself towards purposes. Any actual benefit from evolution not related to natural selection is serendipitous at best, my friend. PMS does not exist for this purpose. It does not exist for any purpose. It simply exists.

While the evidence supporting this theory is thin at best, it would fall under the purview of natural selection - women dumping an infertile partner in order to hook up with a fertile one have a better chance at producing offspring, and thus securing their continued spot in the gene pool.

Describing it as "it exists for a purpose" is indeed technically wrong, as it'd be "it exists because it bestowed a benefit".

I'm not an expert on early and prehistory, but I would think that during the time periods where this research might be valid women did not have the social ability to end relationships, infertile or otherwise.

There's a good many thousands of years when relationships as such did not really exist, but were mostly two people shagging, and raising the subsequent offspring for the first few years.

And even after that, this theory suggests that it didn't give them greater inclination to end a relationship, just be so annoying that both parties want to end it.

 

[Rhykker]

I'm not an expert on early and prehistory, but I would think that during the time periods where this research might be valid women did not have the social ability to end relationships, infertile or otherwise.

I believe the implication is that the man would be repelled by the PMS and end the relationship himself.

 

[Rhykker]

Why is it people assume PMS was selected *for* rather than not yet selected *out*?

You could write a similar article on myopia; after all, a gene that keeps you from seeing how butt ugly you are to each other is going to help produce offspring, right?

Hahahahah... You were almost onto something until I realized how easy it is to kill the guy who can't see well.

 

[Baresark]

the family unit that is the most successful and common is what is commonly known today as the "nuclear family". That is a mother, father, and two offspring.

Do not forget that not so long ago infant mortality was much, much higher than today.
So you might give birth to seven children, but only two might survive to reproduce.

Infant mortality rates shot through the roof post civilization. Prior to 10,000 BCE, smaller family units were the norm, or at least according to some anthropologists. The best rate of success was greatly increased when not having more kids than you could hope to find food for and protect. Even if you could have 7 kids, you more than likely would not be able to both feed and protect the majority of them. In primitive societies, most people were also nomadic, so a woman who spent a 7-10 year chunk of her life pregnant or feeding would be to big of a burden on a small society.

It also seems to work under the assumption that a people in ancient societies always sought to have a huge number of offspring, only evidence shows that prior to 10,000 BCE, the family unit that is the most successful and common is what is commonly known today as the "nuclear family". That is a mother, father, and two offspring.

Is this the case? I do not study anthropology so I am not familiar but from looking at some "primitive" cultures you often see polygamous units and in old civilization (those that came after 10,000 BCE) the most successful did seem to have various concubines and wives (see ancient Israel, Egypt, Mesopotamia, etc.). I honestly have no idea so this is a serious question.

A polygamous family unit was not normal for most of society. Only the extremely rich or powerful had such things. When it comes down to it, more kids than can be cared for is a burden. That is why humanity used to value kids so little during the first 9,500 years or so of "civilized" life (that and for a while an extremely mechanistic view of children was the norm for quite a while). If you had a farm and gave birth to one too many children, you might have just left it in the yard and let the pigs eat it. This is a thing that really happened (which is why I say fuck you to people who think humans are worse than ever). That said, you can still see the practice of the nuclear family in modern primitive societies. Native Americans, some African tribes, and the Native people of Northern Japan and Russia. That is of course assuming that they haven't changed, we don't have proof of.

It is, however, important to understand that nothing we think we know is absolute. The main reason the many children thing is common knowledge is because in recorded history we have seen it. Anthropologists study primitive societies and remains of them as much as they can and try to come up with the best understanding they can. It makes more sense to have smaller families when things are scarce, which doesn't mean all societies come to the same conclusion. It's more than likely there were people in every society that had "too many" kids, no matter how far back you look. But in remains of small societies, this has not been observed, to my knowledge.

I'm not an expert, I just read a lot, so I could be butt ass wrong about all of it.

 

[Ukomba]

Seems more likely that the far more complicated nature of female biology and hormone interaction can have unusual effects on brain chemistry. This evolutionary trait idea assumes

1. That early and pre-humans were monogamous.
2. That a female, after driving one male away, would then still be desirable to other men.
3. A female exhibiting regular PMS would be allowed to stay in the society.
4. That it was more common for the male to be infernal than the female.
5. The lack of offspring wasn't enough to clue the male and female in to the fact that the breeding wasn't working.

All of those assumptions seem questionable at best. Behavior like that seems more likely to be a negative survival trait in a primitive social community.

 

[eberhart]

The best rate of success was greatly increased when not having more kids than you could hope to find food for and protect. Even if you could have 7 kids, you more than likely would not be able to both feed and protect the majority of them. In primitive societies, most people were also nomadic, so a woman who spent a 7-10 year chunk of her life pregnant or feeding would be to big of a burden on a small society.

That doesn't mean "permapregnancy" was not happening though, unless there are some data that back this up. Are there some decent methods to prove what was the actual number of children raised by an average family (and I mean physical sources) rather than merely a calculation that a specific number of children was beneficial? If several thousands years of more recent history are of any indication, infanticide "ad hoc" could've been much easier to figure out rather than some "natural" version of a contraception. There's an apt number of examples from behind the fence, where our various cousins live. Not sure which version of animal birth control should we presume for our ancestors though - and they vary a LOT.

Same about being a burden - it merely implies there's a cost, do we have any clue how a group defined efficiency and priorities in the first place? There's a trap in assuming the most reasonable version where conflicting instincts are involved. Not to mention survival of the family would've been in danger only if it followed "feed everyone" rule in the first place. There's enough of examples where "parents eat first" to doubt that.

As for the success - there's more to life/death than quantifiable goods that have to be divided. Disease, climate, accidents, conflicts, mistakes, birth itself, anything out of the ordinary - they all can produce an impressive death count on their own. Plus - even if we choose to believe those nomadic societies were trying to stick to 2+2 strategy, how could they even dream of accounting for infant mortality rate in any other way than... a "shotgun approach"? If decent number of kids in an entire group was the only "social security" that could be counted on, they had no luxury of "wait and see", certainly not with their lifespan. If anything, agricultural society seems to have at least lesser amount of variables to account for in comparison.

 

[Lightknight]

Wow... Rhykker, I usually enjoy your articles but your use of "bad" in this context is incredibly offensive to infertile men and women. Maybe you can imagine why an infertile male or female would be hurt by you saying the relationship is therefore inherently bad because he's shooting blanks or her uterine wall doesn't allow implantation? These titles really need to improve. I'd call it a low blow but surely that'd just come off as cheesy word play.

FYI, being around a pregnant woman can be like PMS on steroids. Holy shit, if you have experienced the mood swings women face in pregnancy then PMS is nothing but a blip on the radar comparatively.

Look, the symptoms of PMS are just because of the change in hormone levels of Estrogen and Progesterone. The cycle is necessary for switching out eggs and mood swings are always going to be an impact of flooding a system with most types of hormones.

 

[Rhykker]

Wow... Rhykker, I usually enjoy your articles but your use of "bad" in this context is incredibly offensive to infertile men and women. Maybe you can imagine why an infertile male or female would be hurt by you saying the relationship is therefore inherently bad because he's shooting blanks or her uterine wall doesn't allow implantation? These titles really need to improve. I'd call it a low blow but surely that'd just come off as cheesy word play.

I apologize if I offended; I come from a scientific background, and I was speaking from a strictly biological, evolutionary perspective, which I realize can sound cold. Along those same lines, I'm a "bad" mate because I wear glasses (and thus cannot hunt as well), I have allergies (which I would pass along to my children as a weakness), I am not physically imposing (and thus cannot defend my mate as well), etc. etc.

I thought I clarified this in the end, but allow me to expand upon it: thankfully, our society has evolved to the point where natural selection no longer dictates how we propagate our species. Despite all my "bad" traits, I can still be a good mate, because society values things other than just biology. Likewise, infertile couples have plenty of options these days, so infertility is no longer really that "bad" of a trait.

Again, I apologize if I offended.

 

[Baresark]

The best rate of success was greatly increased when not having more kids than you could hope to find food for and protect. Even if you could have 7 kids, you more than likely would not be able to both feed and protect the majority of them. In primitive societies, most people were also nomadic, so a woman who spent a 7-10 year chunk of her life pregnant or feeding would be to big of a burden on a small society.

That doesn't mean "permapregnancy" was not happening though, unless there are some data that back this up. Are there some decent methods to prove what was the actual number of children raised by an average family (and I mean physical sources) rather than merely a calculation that a specific number of children was beneficial? If several thousands years of more recent history are of any indication, infanticide "ad hoc" could've been much easier to figure out rather than some "natural" version of a contraception. There's an apt number of examples from behind the fence, where our various cousins live. Not sure which version of animal birth control should we presume for our ancestors though - and they vary a LOT.

Same about being a burden - it merely implies there's a cost, do we have any clue how a group defined efficiency and priorities in the first place? There's a trap in assuming the most reasonable version where conflicting instincts are involved. Not to mention survival of the family would've been in danger only if it followed "feed everyone" rule in the first place. There's enough of examples where "parents eat first" to doubt that.

As for the success - there's more to life/death than quantifiable goods that have to be divided. Disease, climate, accidents, conflicts, mistakes, birth itself, anything out of the ordinary - they all can produce an impressive death count on their own. Plus - even if we choose to believe those nomadic societies were trying to stick to 2+2 strategy, how could they even dream of accounting for infant mortality rate in any other way than... a "shotgun approach"? If decent number of kids in an entire group was the only "social security" that could be counted on, they had no luxury of "wait and see", certainly not with their lifespan. If anything, agricultural society seems to have at least lesser amount of variables to account for in comparison.

While all of that is true, if you read the rest of my previous statement, anthropological studies point towards the "nuclear family" unit in primitive societies. We can sit here and talk about what we think all day long, the only issue is there hasn't been any findings of larger family units in primitive remains, so far as I have read about. It may be out there and I haven't read about it. I only go by what is there as proof far more than I what I think is possible. You are also suggesting that the world was a death ridden place, but any society works towards the relative safety of it's people. That means education about the world around them such as avoiding larger animals that can kill them, avoiding poisonous or dangerous food, and primitive morning and burial rituals worked against disease development. Also, they were not trapped together in small spaces so there isn't a large danger of a sickness spreading through a whole society.

Like I said previously, I could be wrong about it. I may be reading the wrong books. But to assume that the only possible way is the "shotgun approach" isn't realistic. I also pointed out that it is more than likely that in every society since the beginning of mankind. There are always people who have more or less kids throughout history. The "nuclear family" is only an approximation from archaeological digs.

 

[Lieju]

I'm not an expert on early and prehistory, but I would think that during the time periods where this research might be valid women did not have the social ability to end relationships, infertile or otherwise.

I believe the implication is that the man would be repelled by the PMS and end the relationship himself.

Because I would eat all their food?
That's how I act a day or few before my period starts. I get really hungry for salty/fatty food.
Dunno if it's part of the PMS though.

Also all women I've ever known have been more annoyed during menstruation because pain and mess.

I don't think this makes all that much sense.
Surely menstruation itself would be better for creeping out infertile men?

 

[Lightknight]

Wow... Rhykker, I usually enjoy your articles but your use of "bad" in this context is incredibly offensive to infertile men and women. Maybe you can imagine why an infertile male or female would be hurt by you saying the relationship is therefore inherently bad because he's shooting blanks or her uterine wall doesn't allow implantation? These titles really need to improve. I'd call it a low blow but surely that'd just come off as cheesy word play.

I apologize if I offended; I come from a scientific background, and I was speaking from a strictly biological, evolutionary perspective, which I realize can sound cold. Along those same lines, I'm a "bad" mate because I wear glasses (and thus cannot hunt as well), I have allergies (which I would pass along to my children as a weakness), I am not physically imposing (and thus cannot defend my mate as well), etc. etc.

I thought I clarified this in the end, but allow me to expand upon it: thankfully, our society has evolved to the point where natural selection no longer dictates how we propagate our species. Despite all my "bad" traits, I can still be a good mate, because society values things other than just biology. Likewise, infertile couples have plenty of options these days, so infertility is no longer really that "bad" of a trait.

Again, I apologize if I offended.

You did clarify that you were talking about something bad in terms of ability to successfully reproduce. I understood that preface as a way to acknowledge that it could be hurtful when said that way but it still struck home a bit. Just enough for me to bring it up.

I think it is just the conjunction of the terms bad and relationship. The term relationship being the more operative component, taking on a more social meaning than successful genes. My wife and I haven't decided to have children yet, so we don't know one way or the other, but I would hate to think of myself or for her to think of herself as not holding up one end of the relationship due to infertility which neither of us would have any control over. That would be a deeply painful experience to view in that way, especially when I have such a strong personal desire to pass on my bloodline. Having less-fit-for-survival traits doesn't make your relationship bad. Being a bad "mate" is not the same as being bad at relationships. But I understand exactly what you mean and there's no need for further elaboration with me as long as you understand my side of things which you clearly do.

Anyways, your articles are always a favorite read of mine. My comment on titles needing to improve is a general complaint that could apply to almost any media outlet and not leveled at you. Though I suppose word-play attention grabbing titles are as old as news itself. I appreciate your considerate response (or any response at all, really) and look forward to reading whatever you write next.

 

[Lightknight]

Seriously though, for this to work it would have to also imply that women don't have wild mood swings when pregnant when in reality they get even worse. Some scientist just tried to look at possible evolutionary advantages and jumped to an unnecessary conclusion when the benefits of the menstrual cycle is the very ability to have offspring at all.

Riddle me this, do animals express PMS symptoms?

 

[eberhart]

While all of that is true, if you read the rest of my previous statement, anthropological studies point towards the "nuclear family" unit in primitive societies.

The question is, how many of those contemporary primitive societies can be considered representative of humans as a whole, at least in case of this topic and associated choices. It could be my false impression, but isn't a significant percentage of currently existing ones bound to a specific climate and conditions? Not sure if there's a decent number of societies in more harsh areas (like eg. far-north?) that are also comparable in terms of development with their eg. "deep jungle counterparts". That does not mean I consider extreme an average environment for our ancestors, but it could mean we are missing a huge part of the picture. Note that I am not claiming anything at this point, more like being curious and doubtful at the same time.

We can sit here and talk about what we think all day long, the only issue is there hasn't been any findings of larger family units in primitive remains, so far as I have read about.

Again - not claiming anything, but it's difficult to categorize findings if we have only limited clues about the society itself - if there was any model that could fit a geographically and climatically (if there's such a word ) diversified and ridiculously long phase of development.

You are also suggesting that the world was a death ridden place, but any society works towards the relative safety of it's people. That means education about the world around them such as avoiding larger animals that can kill them, avoiding poisonous or dangerous food, and primitive morning and burial rituals worked against disease development.

True, but the efficiency of those methods hasn't been overly impressive in the past. Obviously, tens of thousands of years can easily mean that it simply resulted in the extinction of those groups that failed *too much* while the system worked at some level. But...

But to assume that the only possible way is the "shotgun approach" isn't realistic.

I prefer to assume "shotgun approach" as the only *effective* way that could realistically work over time. What else was there - proto-contraception? Not really encouraging if preventing pregnancy is the main goal. Abstinence? We still have to figure out that one Lucky guesses about future mortality rate and failure of unlucky groups? Selective breeding? Hm, this one could have some merit, but... quite a lot of talking necessary (and a knowledge I don't have). This is my main issue - reducing number of pregnancies would require a certain amount of know-how and resources and/or quite a bit of social development. Reducing number of children was less complex as it could happen either by simple action, inaction or regardless of any - and we can observe certain aspects that seem already pretty well developed in ancient societies, along with myths and rituals.

As for findings itself - I honestly don't know how they are interpreted in the first place. The amount of certain skeletons among random groups? Burial sites, with the assumption that eg. discarded children even got there? Not to mention a nomadic lifestyle that could also exclude probability of reconstructing a picture to a significant extent.

Still, that's all I can do at this point - accept your answers about the data, express doubt about their interpretation.

 

[lacktheknack]

Note, most women do not experience PMS, and its actually contested if it even exists in the first place. This theory is illogical.

*citation needed*

Clearly, you've never lived for ten years with a sister in a state of permanent menstruation.

 

[PunkRex]

Seems more likely that the far more complicated nature of female biology and hormone interaction can have unusual effects on brain chemistry. This evolutionary trait idea assumes

1. That early and pre-humans were monogamous.
2. That a female, after driving one male away, would then still be desirable to other men.
3. A female exhibiting regular PMS would be allowed to stay in the society.
4. That it was more common for the male to be infernal than the female.
5. The lack of offspring wasn't enough to clue the male and female in to the fact that the breeding wasn't working.

All of those assumptions seem questionable at best. Behavior like that seems more likely to be a negative survival trait in a primitive social community.

I can see where he's coming from but PMS isn't a thing in other animals, as far as I know. Human history is a game of clans and territories, women would have had to move around a lot, a trait that makes them more aggressive to this constantly changing life style seems kind of detrimental.

 

[PhiMed]

I think that is a stretch, to be quite honest. It works under the assumption that it's necessary for PMS to exist to reduce the likelihood of a woman staying with a man who is not producing offspring.
No. It works under the assumption that an emotional-physiologic adaptation that causes relationships which have not produced offspring to end will be more likely to result in viable offspring of the organism which possesses that trait.

Only, it's been shown that sex is not solely for reproduction in humans.

Irrelevant. Evolution is based on the premise that pairings which produce the most viable offspring pass on their traits, while those that produce fewer offspring do not.

Sex is also a means of keeping the bond between a man and a woman strong so they stay together to raise offspring.

Unless you're implying that this will result in a higher likelihood that their offspring will survive to reproduce, this is also irrelevant. Evolutionary stress does not care about an individual organism's emotional well-being.

Women have other impulses as time goes on that strengthen their desire to have a child. PMS need not ever exist when a great many women seem to want to have them anyway.

I don't think that there is any way you could interpret this article that could possibly be seen as an argument against this point.

It also seems to work under the assumption that a people in ancient societies always sought to have a huge number of offspring,

Again, irrelevant. Evolution does not care what individual organisms "seek". The only thing that matters is how many of their offspring survive to reproduce.

only evidence shows that prior to 10,000 BCE, the family unit that is the most successful and common is what is commonly known today as the "nuclear family". That is a mother, father, and two offspring.

Quantifiably false. "Successful" from an evolutionary standpoint relies only on the number of progeny that reproduce. If a pair only replace themselves, then their genes will not propagate. Simple as that. 50% of the population has the genes of Genghis Khan as part of their genetic makeup. I'd say that, from an evolutionary perspective, that is one successful organism. Do you think he did that by just having one son and one daughter with one woman?

Also, people seem to be working under the assumption that all traits people have are beneficial for one reason or another. That is completely false. Some traits people just have because that is how it happened. Just because the trait exists does not mean that there was ever an evolutionary advantage to having it.

Nope. Genes that persist in large numbers do so for a reason. If you are referring to traits which have an incredibly low frequency, then perhaps this point could be defensible, but for a trait to be this pervasive, there must have been an evolutionary advantage to it at some point. Otherwise, it would not have become so ubiquitous.

 

[Baresark]

snip

I would love to respond to what you said, but I don't play the break down and approach idea by idea game.

 

[PhiMed]

snip

I would love to respond to what you said, but I don't play the break down and approach idea by idea game.

So, you dislike how I structured my post, so you can't be bothered with responding, other than to say you object to the way in which I wrote it? That's a bit petty, isn't it? If you don't want to respond, then don't. Don't just criticize how I arranged the text, then take your ball and go home. It's a good thing they're no longer disciplining low-content posts here, because this would pretty much be the definition of one.

I only chose to present it that way because quoting your post in its entirety in one block, then referring to your individual points before I explained why I took issue with them would be too cumbersome. I don't feel like I was disrespectful or insulting in my post, but I feel like your post was supposed to make me feel bad about... something. I don't really understand why you're taking offense to compositional structure, rather than content.

 

[Baresark]

snip

I would love to respond to what you said, but I don't play the break down and approach idea by idea game.

So, you dislike how I structured my post, so you can't be bothered with responding, other than to say you object to the way in which I wrote it? That's a bit petty, isn't it? If you don't want to respond, then don't. Don't just criticize how I arranged the text, then take your ball and go home. It's a good thing they're no longer disciplining low-content posts here, because this would pretty much be the definition of one.

I only chose to present it that way because quoting your post in its entirety in one block, then referring to your individual points before I explained why I took issue with them would be too cumbersome. I don't feel like I was disrespectful or insulting in my post, but I feel like your post was supposed to make me feel bad about... something. I don't really understand why you're taking offense to compositional structure, rather than content.

I wasn't insulted, but the constant breaking down of posts has, in my experience, always lead to the central idea of a post being left behind. You end up responding to little things here and there and then the whole reason for the post is lost.

But I will, in the interest of debate, respond to your post... though I'm not going to break it down as you did.

Only, it's been shown that sex is not solely for reproduction in humans. Unless you're implying that this will result in a higher likelihood that their offspring will survive to reproduce, this is also irrelevant. Evolutionary stress does not care about an individual organism's emotional well-being.

You improperly broke up these ideas, one of the reasons I dislike breaking down whole statements into individual ideas. Both parents present greatly increases the likelihood that offspring will survive. It's the presence of both parents that increase the likelihood of survival. Sex is also a way of keeping the man and woman interested in each other because humans have a long period of time before one of our offspring is capable of caring for itself.

Quantifiably false. "Successful" from an evolutionary standpoint relies only on the number of progeny that reproduce. If a pair only replace themselves, then their genes will not propagate. Simple as that. 50% of the population has the genes of Genghis Khan as part of their genetic makeup. I'd say that, from an evolutionary perspective, that is one successful organism. Do you think he did that by just having one son and one daughter with one woman?

Number of progeny is completely irrelevant if you cannot ensure their survival to adulthood. More mouths to feed and more attention divided between a large number of offspring does not ensure survival of the young. In nomadic societies food is not ensured (as it was not for the first several thousand years of civilization). It's easy to point out to a single incredible instance of genetic propagation and call it the most successful. I also pointed out in my previous posts that most people were not rich or powerful enough to see so many young survive. Forget the fact that my references were EXCLUSIVELY aimed at pre-civilized life and not anything that happened after 8,000 BCE. We know that in the civilized world (ie. time when humanity settled down into non-nomadic societies and city states), it was common place for the "shotgun approach" to be used. Food was a lot more scarce and hard to come by for large and growing civilizations than it was for primitive hunter-gather societies who's size was limited by the amount of food that could be found or hunted.

Nope. Genes that persist in large numbers do so for a reason. If you are referring to traits which have an incredibly low frequency, then perhaps this point could be defensible, but for a trait to be this pervasive, there must have been an evolutionary advantage to it at some point. Otherwise, it would not have become so ubiquitous.[/qhote]

You are incorrect. A trait with no downside will persist, even if it does not provide any kind of advantage. It simply has to be a common trait in the population and not be selected out (ie. offer a disadvantage).

 

[Baresark]

snip

I would love to respond to what you said, but I don't play the break down and approach idea by idea game.

And just what is wrong with that approach?

It has in my experience, always lead to the central idea of a post getting lost. It always seems to be broken down to the point that there is debate of language used rather than ideas being exchanged. If you like to break apart posts like that, that is absolutely fine. I'm not saying don't, I'm just saying that I have never seen it to be advantageous.