Tuesday, 19 February 2013

Modern sub-fertility may be a pathologically slow life history, triggered by a supernormal stimulus of modernity

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The universal pattern of chosen sub-fertility in all Western societies (except among the devoutly, traditionally-religious) could be conceptualized as being a consequence of an extreme 'supernormal' stimulus operating on the speed of life history.
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A supernormal stimulus is a maladaptively exaggerated  consequence of evolved behaviour, triggered by a super-powerful stimulus that has not been encountered in evolutionary history.
So a seagull may nurture a fake plastic egg with garish colours in preference to its own fertilized natural egg, or a male butterfly mate with a crude cardboard mimic of a female with unnaturally well-defined wing patterning.

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Life history speed refers to the reproductive strategy on a scale from FASTER - with rapid maturation, focus on mating effort, and a priority of achieving earlier and more frequent reproduction with less individual care (resources) per child; to SLOWER - with delayed sexual maturation, a long-termist socio-economic plan taking priority over reproduction, fewer offspring, and each child provided with more parental resources. 
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The decision between faster or slower life history strategy is probably 'set'  in childhood in response to environmental stimuli which (under ancestral conditions) have signaled what was likely to be the most adaptive reproductive strategy (that which is most likely to lead to the greatest number of viable offspring). 

Signals of instability (perhaps experiences of starvation or disease, absent father, chaotic environment) lead to a perceived risk of earlier death; and therefore more rapid sexual maturation and early mating efforts implicitly aimed at parenting a larger number of offspring - on the expectation that not children all will survive to adulthood.   
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In contrast, signals of a stable environment trigger a slower life history, because under stable conditions a slow maturing individual with higher parental care can build the ability to exploit specialized niches in a situation of high competition. 
(For example, delaying reproductive effort and instead embarking on a long apprenticeship to become a high status and economically secure specialist craftsman; or delaying sexual maturation to 'build' a more beautiful and long-lastingly attractive face and body.)
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It is possible that extreme prosperity/ comfort/ lack of hunger/ lack of disease stress/ unprecedented security and stability (or some other aspect of modernity) is acting as a supernormal stimulus to the 'mechanism' of life history calibration in early childhood.
So that an environmental signal (of a type unprecedented in human evolutionary history) may be triggering such a slow life history that (in the real world) it is incapable of replacing the current population - and is therefore maladaptive.
Because the supernormal signal (whatever it is) is unprecedented in evolutionary history, humans behaviour in response to that signal is not adaptive - and as it turns out the response is actively maladaptive, or counter-productive: a response which necessarily harms reproductive success by leading to chosen sterility (or sub-fertility).
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The failure to reproduce can perhaps be conceptualized as an extreme, pathological lack of urgency concerning reproduction; when people are giving reproduction such a low priority that in practice reproduction is sub-replacement or indeed never actually happens - they run out of time.
(About a third of women college graduates in Western Europe currently choose to have zero children.)
...Rather as if each child implicitly responded to the ultra-secure, supernormal stimuli of modern childhood with a built-in but subliminal expectation that she will live for 200 years with more than a century of youthful fecundity and vigour - and delays reproductive effort accordingly.
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So that a twenty year old women who is planning a successful career for which the training period extends perhaps into post-reproductive age, may nonetheless express a desire to have a large family... at some point, eventually - maybe in about fifty years time... 
(or so it feels at a subliminal level, so her instincts may be saying unconsciously - in response to the supernormal stimuli of childhood).
Of course, in theory, individuals can choose otherwise - can choose to make marriage and family an early and urgent priority.
But this choice by an individual is unlikely when reproduction does not feel like an urgent priority - except when this feeling is over-ridden by social factors: specifically when there is cohesive and psychologically-effective support-for early marriage and family (and/or sanctions-against delayed reproduction); and this only happens in devout, cohesive traditionally religious groups.

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It is interesting to speculate on the specific identity of this putative supernormal stimulus which (I speculate) is sabotaging human life history; but with science in its current, diabolical, state the specific identity probably will never be known.
(Or if the supernormal stimulus is indeed discovered, the finding would probably never be accepted generally, because it will no doubt conflict with Leftism. After all, most true things do conflict with Leftism...)
Either way, natural selection will deal with the problem by (at the individual selection level) replacing the population who are vulnerable to the life history delaying effects of the supernormal stimulus with individuals who are immune to its effects - leading to a selection pressure for faster life history; and also (at the group selection level) by differential growth of devoutly, traditionally religious groups in which individual choice is shaped-by or subordinated-to the social norms.
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So the prediction/ prophecy (supported by other lines of evidence) is for most people in most places an unstable and chaotic, low-complexity social world - consisting of short-termist, fast life history, cognitive generalists; and another very different   higher-complexity system, consisting of of slower life history 'communitarian' religious groups, with lower mortality and longer life expectancy and fewer offspring per women, with higher levels of specialized skills - and in which above-replacement fertility is encouraged/ maintained/ enforced by socially-regulated marriage and family fertility. Probably, the slower life history system will be the stronger of the two.
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NOTE ADDED 21 Feb 2013: I would tend to go with nutrition; not so much 'good' nutrition as the absence of periods of starvation stress (from famine, or from serious illnesses lasting a week or more - e.g. long illnesses with with nausea, vomiting, anorexia, hypercatabolism etc). In other words, few periods of starvation stress triggers slower life history - while a *complete absence* of periods of childhood starvation might be the supernormal stimulus that triggers a pathologically slow life history. This hypothesis would be testable.

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26 comments:

Thursday said...

I have heard tossed around the idea that intelligence is negatively correlated with fertility, except among the religious, where it is the opposite. It may even have been you. But is there a cite for this?

If so, we are headed for a future where a religious elite rules over a horde of low IQ individuals.

Daybreaker said...

"Signals of instability (perhaps experiences of starvation or disease, absent father, chaotic environment) lead to a perceived risk of earlier death; and therefore more rapid sexual maturation and early mating efforts implicitly aimed at parenting a larger number of offspring - on the expectation that not children all will survive to adulthood."
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If "missing father" is a cue for fertility the children of "friends with benefits" relationships (and worse) ought to be plumping for early fertility in a big way. Instead, the last time I read up on this, the emotional wounds of divorce and growing up in unstable situations were leading to less reproductive success (at least in the mostly white families studied). The kids, when they grew up, were less happy and less functional, and low on romantic trust (obviously). They were willing to defer reproduction to secure their own status and ability to make a buck independently of whether a partner would stay true.

Elizabeth I had plenty of family instability. It didn't lead to her plumping for early marriage and lots of babies. It led to her dying a virgin queen.

Bruce Charlton said...

@T - Anyone from Francis Galton to Richard Lynn - very solid finding: there is even a Wiki page on the subject.

@D - Fertility is not the same as fast life history - Mormons have very slow life history but are fertile.

The point is not that I already know what the supernormal signal is which triggers sub-fertility, but to suggest that it would worth looking for the signal/s.

Or else to acknowledge what makes the signal unneccessary: old-time religion.

Daybreaker said...

The point is not that I already know what the supernormal signal is which triggers sub-fertility, but to suggest that it would worth looking for the signal/s.
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This I agree with. And I agree with you that the main barrier to the needed research would be political correctness.


Or else to acknowledge what makes the signal unneccessary: old-time religion.
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I agree with that too.

But (as I said earlier - not published) old-time Christian religion does not fail gracefully. It can look great (on the whole) while it stays in the saddle, but it breeds terrible enemies, and when they get in charge the post-Christian state is likely to be appalling. I don't even think I need to point to the specific mechanisms - that's just an obvious reality now.

Mangan said...

Bruce, this is a brilliant idea. Wish I'd thought of it.

Bruce Charlton said...

@Dennis - that's how it seemed to me! - but these initially-brilliant things of mine have a tendency to fade over time...

Bruce Charlton said...

As to a guess at the specific nature of the supernormal stimulus - it would have to be something/s that began to operate right back around 1800 among the upper classes (one sign of it would be the growth of feminism from that era onwards); near the beginning of the rise in prosperity (per capita) due to the agrarian/ industrial revolution - because that is when the current demographic transition began. Then the signal progressively went down the social classes.

Probably something linked with 'increasing prosperity', literacy, cognitive specialization... that kind of thing.

Alternatively, it may be something to do with 'individualism' - and an escape from the repression entailed by group-selection (group selection only works when individual-satisfaction-maximizers - free riders - are sufficiently prevented or eliminated).

C. said...

One thing I've noticed is just how young American people today tend to look. I don't just mean physical age or lack of wrinkles, I mean that they lack this indefinable sort of adult *presence* even at their most mature and stable.

It's most striking when you look at female performers from the 80s and earlier and compare them to the ones today (if you can stand it). Even if you're comparing a 20-year-old singer from then and a 35-year-old from today, the earlier one somehow strikes you as "this is an adult person" and the later one doesn't.

Aaron said...

I've often thought that modern life is mismatched with our lifespan and fertility window, that modern life would require a much longer life and much later fertility window. In the past, and even in societies that lacked a formal caste system, there were a fewer number a easily understood roles to move into. Now people spend half their lives in the educational system and jockey to social climb in some eternal game of musical chairs.

Daybreaker said...

@D - Fertility is not the same as fast life history - Mormons have very slow life history but are fertile.
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It's not the same but it's related. If both extended family A and extended family B have three viable babies per woman, but extended family A has them at ages 15-18 and extended family B has them at ages 25-28, extended family A is going to blow away extended family B.

Eventually extended family B's fertility will be crushed by the need to pay for the swarming babies of extended family A, which are there already. You'll get an Idiocracy effect: for the forward-looking and cautious, it's never an ideal time to have babies.

Bruce Charlton said...

@D - it may be that you don't fully understand life history theory - because what you say is not true in some environments. Otherwise all life histories would be fast.

FHL said...

Hello! I still read this blog! I haven't posted recently because I have been busy with work at a new job and most of your recent posts involve Mormons, of whom I know absolutely nothing about and have little interest in, mostly since I don't actually know any Mormons.

But I must say I am overjoyed that "intermittent blogging" means just that!

People were commenting on your presumed departure from the Orthosphere in such a way that made me anxious that I too had to make a comment before you were swept up onto a fiery chariot heading up towards the heavens where you would disappear forever, your writing fading away into the wasteland of forgotten websites, mentioned only once or twice a year in whispers in internet corners by a handful of anonymous persons, who would probably end up misquoting you anyway.

Glad that didn't happen! Phew! Forgive me for saying so, it is quite selfish of me, but I am relieved to find out that you're not Holy enough to be whisked away into the clouds on a flaming chariot.

:D


Relating to this post, I may be mistaken, and I will admit I am not sure I fully understand this post, but I think that perhaps your ideas are very similar to my ideas on why "game" seems to work so well (I know you don't like the "game" blogs, and I don't like them either, but I must say that from what I read on them some time ago, they give a fairly accurate picture of the current state of affairs) , and why the current state of finding and keeping a spouse is so messy and screwed-up nowadays. I don't have the energy or time right now to fully flesh out a theory, but I might post more on this later. In short, a woman's natural and reasonable desire for a competent, strong, and unshakable husband as well as a man's natural and reasonable desire for a loyal and loving wife has been routed into the most twisted path by a culture and economic/technological situation that screws with the natural order and conceals reality, leading to the present state of chaos.

Bruce Charlton said...

@FHL - glad to know you are still 'lurking'...

Daybreaker said...

@D - it may be that you don't fully understand life history theory - because what you say is not true in some environments. Otherwise all life histories would be fast.
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I'm sure my understanding can be improved.

I'm not oblivious enough to think all life histories must be "fast". It only looks that way when my main points vanish.

Some bloggers like to publish comments very selectively. I'm cool with that. If I didn't like your blog, I wouldn't be here. It suits me to know that any comment I have published here helps your blog to be exactly the way you want it to be, otherwise you wouldn't have chosen to publish it. The way I look at it, focusing on the positive, I'm trying to help the blog, and you're helping me do that by applying a very strong editorial hand.

Bruce Charlton said...

@D - thanks for not taking offense! But I do value those comments I publish, and I do at least read and ponder the ones I don't.

Thursday said...

The finding that intelligence in modern societies is negatively correlated with reproduction in the general population is well established.

But is there data that the reverse is true for religious people in modern societies? That is that there is actually a positive correlation between intelligence and fertility among the religious.

FHL said...

Haha! I just noticed something funny.

When I wrote "But I must say I am overjoyed that 'intermittent blogging' means just that!" I actually meant it in the serious and literal sense. I was not being sarcastic.

You see, I took "intermittent" to mean something like "irregular" or "whenever I get an idea," which could be in a couple of a months, or the very next day. The reason I placed it in quotation marks was because I simply wanted to refer to your previous post, NOT because I was poking fun at you. Honestly. And when I said that stuff about you riding the chariot into the heavens, I was poking fun at the other comments as well my myself, because I, like others who commented, worried that "intermittent" might not actually mean "irregular" but rather "never again." So when I said I was glad that you did not just disappear, I was being serious. I meant "I am glad that you are writing something, whether intermittently or not, rather then never writing again."

I mean, I didn't seriously think you'd get swept away in a flaming chariot, but I thought that maybe nothing new would come to mind or maybe you would decide to not share your thoughts anymore and you would never post anything ever again.

Now here's where it gets funny.

When I first read your reply, I thought, "How nice. He's glad that I'm still reading." But then I thought about those periods at the end of your statement, that ellipsis. And then I thought about the the quotation marks around the word "lurking." And then I thought "Wait a minute... am I being mocked?"

So I looked back at my post and thought about how you could have taken it. It was all too clear. I think you thought that I was poking fun at you because you continue writing daily posts after telling people that it was going to be intermittent. But you see, I didn't notice that at first, because I took intermittent to mean "whenever I had something to talk about" so I just figured you had something to talk about.

Now here's where it gets funnier.

I actually wish that I had intended it in the way that you took it (if that is the way you took it), not to insult you but in harmless jest, because you actually have a history with this sort of thing. I am not sure if you notice this or not (I assume you must since you noticed it in my message even though it wasn't my intention to put it in there) but I remember at least one occasion when you stated you were taking a break from blogging only to come back within the same week and pound out some of your best posts. I remember thinking to myself: "If that's the quality of writing he produces when he decides to take a break from writing then he should always be on break. Based on previous experience, I can say that if Dr. Charlton ever decided to quit writing altogether, he'd have a stunning masterpiece in publication at the printing press two weeks later."

Bruce Charlton said...

@FHL - It is a matter of intentions.

Previously I intended to write a post every day, and if I had nothing to say I would cobble something together; and if I didn't feel like it - I would make myself.

Now, when I wake-up late with a blank mind, like today, I just won't force-out a post...

Or maybe I will?

Bruce Charlton said...

@Thursday - "The finding that intelligence in modern societies is negatively correlated with reproduction in the general population is well established. But is there data that the reverse is true for religious people in modern societies? That is that there is actually a positive correlation between intelligence and fertility among the religious."

This is the situation for Mormons - http://mormonfertility.blogspot.co.uk/

This was also the pattern, I believe, in many large scale agricultural societies such as Medieval Europe - which is why higher intelligence evolved in such times and places.

But before the industrial revolution, fertility is only half of the picture - since child mortality rates were very high; probably approaching 100 percent among the poorest classes, and extremely high among the ruling class. The advantage of the intellectual middle class was probably not so much in higher rate of births, but in lower rate of deaths.

JayMan said...

"Slow" life-history, in humans, is a product of evolving in a stable, albeit Malthusian environment. All people who have a history of living in a high-latitude civilization will predominantly exhibit a slow life history.

The reason is simple: in a stable, but resource-limited environment, quality starts to be preferred over quantity. One can have a fast life-history and have lots of children, but that ultimately will be a less successful strategy than having fewer children and investing heavily in each (giving each a leg up in the competition to obtain resources for their own families).

Such conditions would have produced traits that conditioned people to seek to attain the means in which to successfully raise a family before trying to do so. In pre-industrial times, this typically meant having a plot of land to farm. Marriage (and hence reproduction) was typically delayed until this could be attained. Apparently, in Western Europe, individuals would either work to earn his plot or wait in line to inherit one (in Eastern Europe and East Asia, plots were subdivided among children and they would marry as soon as they would attain one). In either case, this created a need to feel "resource secure" before having children.

In today's world, we have made the hoops to attain the keys to unlock resources many and long (education, career). While this is not a big fertility hit for men, this is a huge menace for women, who wait so long to have children that they fall short of their intended goal. Indeed, it is not that educated women as a group lack the desire to have children, but they put off family formation during their youth for so long, that they fall far short of their desired number of offspring.

Cost of living, and its maker as a signal of resource abundance, is a powerful force acting upon fertility. Since cost of living is heavily affected by population density, we can see that this has produced a strong relationship between the two.

Low fertility is not a permanent state, but a temporary adjustment of the human population to new societal conditions. Eventually, fertility WILL rebound, as the genes that predispose people to fail to reproduce in the current environment become selected out and the genes that lead people to reproduce anyway become favored.

Bruce Charlton said...

@J - I think you misunderstand my argument. What you describe will indeed happen over a multi-generational evolutionary timescale - but what I am talking about here is a calibration of an individual person's life history in response to childhood experience.

An early example of this kind of research would be: Father absence and reproductive strategy: An evolutionary perspective P Draper, H Harpending - Journal of Anthropological Research, 1982 - JSTOR - which can be accessed via Google Scholar

JayMan said...

I'm not convinced of most claims about physical maturation rates being affected by environmental cues. We know that the age of maturation has been declining for both sexes, but we have no real idea on the cause(s). The most likely source is better nutrition, or, more accurately, as you noted over at Magnan's, fewer periods of "starvation stress" in today's youth.

As I noted over at Magnan's, the association between fatherlessness and early maturation is caused by heredity.

Indeed, that presents a confound to any potential test of the notion that maturation is affected by environmental cues: how do you control for heredity?

But going further, the onset of maturation isn't related to the modern decline in fertility, since those trends clearly go in opposite directions.

Bruce Charlton said...

@J - like I said - Life History can evolve to become faster or slower over generations; and *also* an individual's life history may be 'set' by crucial experiences in early life (maybe even in the womb - quite a lot of evidence to support that).

Two processes.

Of course, whether one or another or both of them is actually happening in any specific situation is a matter for empirical investigation.

But there is no way that sub-replacement fertility in a population can be adaptive - and so it could not have evolved. I think the mechanism has to be a pathology, and it has to work at the individual level.

Perhaps it never emerged before because previously there was always religion - which has been a major mechanism for group selection. As religion has dwindled, so individualism emerged, and pathologies of Life History were left unopposed.

JayMan said...

"and *also* an individual's life history may be 'set' by crucial experiences in early life (maybe even in the womb - quite a lot of evidence to support that)."

Pre-natal forces I'd quicker believe. That is otherwise known as developmental noise.

"But there is no way that sub-replacement fertility in a population can be adaptive - and so it could not have evolved. I think the mechanism has to be a pathology, and it has to work at the individual level."

Sub-replacement fertility that we currently see isn't "adaptive" per se; it's adaptation in progress. We are currently witnessing ongoing selection in response to changing environmental conditions (one with lengthy educations and effective contraception).

"As religion has dwindled, so individualism emerged, and pathologies of Life History were left unopposed."

Strictly speaking, this is true. But this is a transient phenomenon. Fertility will rebound as evolution adjusts the population to modern conditions.

Bruce Charlton said...

@JM - Well, sort of. The world population has been growing incredibly rapidly, to that is not problem, as such. But I am trying to explain an astonishing thing, biologically speaking - chosen subfertility in conditions of unprecedented material abundance.

tyrionlannister69 said...

" In contrast, signals of a stable environment trigger a slower life history, because under stable conditions a slow maturing individual with higher parental care can build the ability to exploit specialized niches in a situation of high competition.
(For example, delaying reproductive effort and instead embarking on a long apprenticeship to become a high status and economically secure specialist craftsman; or delaying sexual maturation to 'build' a more beautiful and long-lastingly attractive face and body.)"


i´m not sure with that, because puberty is happening earlier. For girls, the age of puberty has been falling since the 19th century. The same period has seen a similar decline for boys. So if Rushton is right about r/K selection, then what is essentially happening is that the dad cultures are beginning to adopt the mating strategies of the cad cultures, because genes that favor that developmental trajectory are spreading within the population. Modern social environments favor a reproductive strategy of early puberty, low parental investment and, especially, low paternal investment, in short, the ‘cads’ are outbreeding the ‘dads.

Natural selection now favoring the “cads” over the “dads”. As sexual relationships become less stable and shorter-term, women will ignore men who are oriented towards stable, long-term relationships.