Anonymous
Imperial China, with elite males polygamy (one wife + concubines = polygamy) allow elite males to obtain more children than poor ones.
The (first) wife and the concubines borne the children of the one male.
It is not important only the children of the wife inherited the estate and nobility titles. If the wife was barren there would be the children of the concubines and, anyway, the children of the concubines had better food, education and chances to find a gainful job or climb the social ladder. This is the same trickle down effect we saw in England.
The difference is in England it was the middle class to trickle down (and up as the nobility died off) where in China it was the nobility/government functionaries to trickle down.

The two rings are round but the themes are completely different.

If there is something resembling the Ring of the Nibelung in Tolkien is the Silmarillon and the accompanying tales of Hurin, Huor and their sons.

The Silmarils are the Gold or the Reno, The Ring is the Crown where Morgot put the gems. Who take the gems for himself is cursed in ruin whatever his power. When one gem is freely turned to the Vala, they send their army to defeat Morghot and his.

The Tale of Hurin Sons is there, with brother, sister, (involuntary) incest, death, the dragon.

The parts are there, but how they are used to build the plot is completely different.

But the must important feature of Tolkien works is the absence of Wotan. In the end, Wotan is the deux ex-machina of all. He know, he plot, he direct the people to obtain what he desire.
In Tolkien, there is no direct involvement of a god to obtain his desired goal. Iluvatar do not interfere with the plot. The decisions of the mortals (elves, Vala, men, dwarves or others are their, they are not influenced by the intervention of a god).

In Italy we say, about the WW2, "Italian soldiers and German officers"

The problem of Italy was, after near 20 years of Fascist regime, the heads of the Armed Forces were selected more for their fealty to the Fascist Party than for they skills. Mussolini, like Saddam, believed to be able to "seat at the table of the peace" paying a few lives of Italian soldier. They both misread the political and military conditions. And both went at war unprepared and paid with their lives.

Hypothesis for reasons for male homosexuality:

I was not aware gays were more frequent for mothers or aunts with many children.

The reason, IMHO, is pretty simple:

1) Mother with few children or one having one gay child will have a much lower fertility in the long run. 1:2, 1:3 is a severe reduction of fertility.

2) Mothers with many children will have a lower reduction of fertility if one male child is gay.

What could be the advantage to have a gay male over many children (of various sex) for the mother or the aunts?
Gays would stay in the family (until 100 years ago, the majority of people lived in farms) and lend their work to keeping the family or, if they worked out, they would leave inheritances to their family members.
This is simply a way to indirectly increase the K factor. This would not be only true for gays but also for disinterested in sex males. They would be the ox of the family.
There was a tradition in the past in Italy, where every good family would have at least one uncle going to seminar and becoming a priest (or a noun for the female). Often, from this position, they would relieve the family from the need to keep them feed, educated, etc. and when they become priests or higher, they would be in position to help their brothers/sisters sons to obtain a good job, access cheaper education, care for the older parents, uncle/aunts, etc.

So, I expect, a reduction of women fertility will result in lot less homosexuals men and more female homosexuality.

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Male are attracted by just matured or near to maturation girls over mature women or too young babes for other simple reasons:

1) If they are the first male having sex with them, there is a larger probability they bond with them forever and give them children.
2) Younger need care and this is expensive (and then become difficult to bond with them for psychological mechanisms preventing inbreeding)
3) Older female (having already know other men or probable to have know other men) are more difficult to bond with the male long term, they could have offspring the male don't want (and causing their death or other damage will not make easier for the woman to bond with the male)

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Women are rarely attracted by younger men because they usually lack the ability to provide for her children. They prefer mature men for this.

My two cents

Paternal age in lower temperature climates could affect the total genetic load?

The surviving children in a tropical setting could be different from the children surviving in temperate/cold setting?

Cold and germs kill in a different way and they should select for different traits.

The women surplus in Europe could have spilled in the near populations?

If a male could only support a female, it make sense to sell the surplus to other men. It would be better than let the die.

If the women sold were "prettier" than the women of the confining populations (but less of the women kept), they would reproduce with their new owner / husband faster than the local women.

Another point: if food was abundant but difficult to get, the old Europeans would have a surplus population spilling continuously to South and East.
They would have a difficult to invade homeland and the ability to push continuously outside.

What would be interesting to understand is the reproductive fitness of cad's children.

If cads have more children and become prevalent in the population compared to dads, their children will have less material support than now (less resource extracted from the dads and transferred to the cads from the government). This is also true in the case of a long economic collapse/crisis.

Cad's children have less support than dad's children but, with the government interference, they receive enough resources to be able to compensate for the lack of paternal investment. If we suppose that an economic crisis will reduce the resources for both groups of children, the cad's will fare much worse than the dad's.

This will put cad's at a disadvantage against the dad's in the mating, because women falling for the cad's children will have even less resources available for their children where women able to monopolize the dad's will be able to extract a lot of resources from them for their children.

In the end it is not how many children have the cad or the dad, but how many children have the women falling for the cad or the dad.

The Inductivist had a few data about it:

Mean number of offspring
Wealthy liberal women (n = 35) 1.60
Wealthy conservative women (n = 43) 2.49

Marital Status and fertility
Mean number of offspring

Women with less than four-year degree (sample size = 1,759)
Married 2.23
Separated/Divorced 2.14
Never-Married .46*

Women with four-year degree or more (sample size = 866)
Married 1.88
Separated/Divorced 1.63
Never-Married .15*

At the end, if the women falling for the cad have a lot less children than the women falling for the dads this will keep the number of cads a bay.

Interesting post.

What could be the reasons of the different falling rate of births for the different groups?
The 2008 crisis hit them all, but Whites, apparently, endured better than the rest.
Do you have some figures about the fertility rates between 1920-1950? Do the effect on the fertility rate was the same or similar? I found some and, apparently, yes. TBR fell faster from higher levels for Blacks than for Whites and rebound faster from lower level for Whites than Blacks.

It appear Blacks are hit sooner and harder and recover later and less than Whites.

The prospect of continuous economic troubles in the future of the USoA make me think the trend of faster declining birthrates for Blacks and Hispanics will continue in the future, where Whites will stabilize and could rebound a little like in the '90s.

I note there is a bump on the graph of TFR for all groups (smaller for Whites) coincident with the housing bubble top and a sharp fall (smaller for the Whites) coincident with the house price top starting.

Do the increase of TFR was linked to family formations? Probably.
This is marked for Blacks. The TFR fall before the bump (delayed births) to allow capital accumulation to buy the home. The home increase in price (people feel wealthier) and they start having children. House prices fall, jobs are lost, people feel poorer and stop having other children, New house formations are delayed.

Thank you for the reply.

Do you think Black (and other)'s TFR could fall under the TFR of Whites if the present economic conditions become worse and stay so for a long (5-10-15 years) time?

In Denmark the TFR of locals is now a bit higher than the TFR of immigrants.

"Milan has the same family system as Sicily according to Todd. How then can you explain the difference in IQ and achievement?"

I don't know Todd, but he is smoking something strong.

Sicily had a lot less advanced economy, much more agriculture and less industry. Also Sicily had a lot of emigration where Milan had a lot of immigration (at least from the Unification of Italy until now).

Self selection of immigrants and emigrants will favor the best, more skilled, with higher IQ. These will adapt to the new place and prosper where the latter will probably return home poor and pissed.

My theory is "guilt" is an effect of the neurotic trait.
People feel guilty when they believe or feel they have not done what they believe was the right thing to do.

The neurotic trait is useful in northern, colder, climates because push people to worry about the future and act to prevent possible bad outcomes. For example accumulating wood and food for the winter.
Guilt is an useful emotion because it gives the drive to make right what was done wrong.
A person feeling guilty would be more prone to confess her wrongdoing to his kin or neighbours. In an harsh habitat this would increase the coping ability of the group, because it would allow the group to fix problems earlier and prevent greater problems later.

A different course of inquiry could be this:
oestrogenisation made women more caring for the children in Europe and allowed/forced an increased paternal investment on offspring.

Do oestrogenisation make women more caring for children and cuckolding less frequent?
Because, if she cuckolds her male provider, she should do it with another male provider and, in ancient time, the previous children would be in a dangerous situation (or at least very disadvantaged).

Maybe it is a chance, but fairy tales talk about the fairy princess menaced by their darker haired/skinned sisters.

Maybe microcefalin variant gene correlate to larger brain just because larger brains/head are more useful in cold climates than smaller brains and smaller heads.

The volume/surface ratio would be better for people with larger brains/heads. This could have some impact on survival ratios.

Exposition to cold can impair thinking. And this could have a profound effect on people not already adapted to cold environments in other ways.

Natural selection just selected for people lasting more time in cold. The other died/never reproduced as fast as the cold resistant.

This is a citation found online
http://www.ski-adventure-guide.com/hypothermiasymptom.html

Medium Hypertermia

"The brain function starts to come up with symptoms of its own.These present themselves by absent mindedness, becoming confused, having short term memory problems.This single hypothermic symptom alone explains why snow expedition victims become lost, even in terrain which is familiar to them."

And this is talking about people able to use clothes made in the last couple of centuries and already pre adapted in many ways (like the hunter/gathers eating meat rich diets able to produce more heat discussed in a previous OP by Peter Frost).

Islam is regarded as an Abrahamic religion just because the Muslims say so. They specifically reject the other books as "corrupted" and cite them only when convenient to them.

If we believe "guilt" is an internalization of paternal teaching and it is an inheritable trait something will follow logically.

1) A "guilt" prone individual will be more receptive to internalize any teaching and rule given by a fatherly figure.

2) Highly intelligent individuals could "virtualize" the fatherly figure if the fatherly figure is lacking or missing. They could drop their real father as a source for the rules they internalize and took someone else or something else.

Highly intelligent individuals, if not properly educated by their family are known to be prone to believe silly memes (from astrology to communism….).
This could be not because they are more intelligent but because the proneness to internalize some belief is associated with higher intelligence.

Brain neoteny could explaining because some individuals are more prone than others to move from a belief to another and internalize them. They are able to internalize them but, until later in age, they are unable to fix them permanently. Maybe before they are communist fanatics then they become muslim fanatics later in life.

It would be interesting a break up of IQ and actual voters.
In many states less than half and probably around a quarter of voters actually vote. And the voters mean IQ is probably not the same as the population mean IQ.

Low IQ people do not vote as much and like high IQ people.