Children of Older Fathers Less Fit

[Angela]

[h=1]Older fathers' children have lower evolutionary fitness across four centuries and in four populations[/h]See:
http://biorxiv.org/content/early/2016/03/08/042788?rss=1%22&utm_source=dlvr.it&utm_medium=twitter

More proof for something that I think we already knew, I think:

"
[h=2]Abstract[/h]"Higher paternal age at offspring conception increases de novo genetic mutations (Kong et al., 2012). Based on evolutionary genetic theory we predicted that the offspring of older fathers would be less likely to survive and reproduce, i.e. have lower fitness. In a sibling control study, we find clear support for negative paternal age effects on offspring survival, mating and reproductive success across four large populations with an aggregate N > 1.3 million in main analyses. Compared to a sibling born when the father was 10 years younger, individuals had 4-13% fewer surviving children in the four populations. Three populations were pre-industrial (1670-1850) Western populations and showed a pattern of paternal age effects across the offspring's lifespan. In 20th-century Sweden, we found no negative paternal age effects on child survival or marriage odds. Effects survived tests for competing explanations, including maternal age and parental loss. To the extent that we succeeded in isolating a mutation-driven effect of paternal age, our results can be understood to show that de novo mutations reduce offspring fitness across populations and time. We can use this understanding to predict the effect of increasingly delayed reproduction on offspring genetic load, mortality and fertility."

It seems the effects aren't really significant modern society.

I wonder if that's as true with maternal age.

 

[Maciamo]

I wonder if the effect are somewhat cumulative for several generations (like epigenetic changes) or if each generation resets the fitness level. If deleterious mutations accumulate in older fathers, then these mutations are inherited by all subsequent generations. If the difference in fitness is only epigenetic or resulting from another biological process, then it shouldn't have any lasting impact over several centuries. The first case is more worrisome as it would mean that people are becoming less fit in countries where parents tend to have children in their 30's (as in the West now, and actually for quite a few centuries in Britain), as opposed to countries with a tradition of teenage marriages and pregnancies, like in many African ethnic groups.

 

[Tomenable]

This contradicts the findings of John Hajnal, who found that areas with higher parental age at offspring conception (North-Western and Central Europe) were developing faster. And other researchers also linked higher average paternal (as well as maternal) age at offspring conception with gradually rising average levels of IQ during the Middle Ages and the Early Modern Era.

This might also explain the difference of few points in average IQ scores between Poland and Western Ukraine. The book linked below (in Polish; about family structures in Pre-Modern Poland) on pages 17-20 explains that in regions such as Mazovia and Lesser Poland people were marrying relatively late (women after 23 years of age, men after 26 or after 27 years of age), while in regions such as Red Ruthenia (present-day Western Ukraine) people were marrying early (around 18-19 years of age for both sexes):

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

Eastern boundary between late marriage culture & early marriage culture more or less corresponded to this yellow line:

https://hbdchick.files.wordpress.com/2012/02/extent-and-spread-of-manorialism.jpg?w=460&h=455

The first case is more worrisome as it would mean that people are becoming less fit in countries where parents tend to have children in their 30's (as in the West now, and actually for quite a few centuries in Britain), as opposed to countries with a tradition of teenage marriages and pregnancies, like in many African ethnic groups.

I really, really don't think that teenage marriages are good for humanity from evolutionary perspective.

Notice that all countries with long-established (at least several centuries old) habits of late marriages are better-off (in all possible ways) than countries with prevalence of teenage marriages, such as Sub-Saharan Africa or the Muslim World. If you read blogs such as HBD Chick or JayMan's blog, etc. you will see that traditional family structures & patterns correlate with many things.

This research is as suspicious as those papers about Neanderthal admixture attributing "all things bad" to Neanderthals.

Angela even speculated, that perhaps Neanderthal admixture slowed down the development of civilization.

In such case I wonder, why haven't Sub-Saharans - who don't have it - colonized Alpha Centauri yet...

Colonizing Alpha Centauri in year 1871 when playing as the Zulus was possible in Sid Meier's Civilization, though:

 

[Tomenable]

Based on evolutionary genetic theory we predicted that the offspring of older fathers would be less likely to survive and reproduce, i.e. have lower fitness. In a sibling control study, we find clear support for negative paternal age effects on offspring survival, mating and reproductive success across four large populations with an aggregate N > 1.3 million in main analyses.

What it means is older fathers = eugenic effects on society. Younger fathers = neutral or dysgenic effects on society.

This study claims that in Western Europe genotypic intelligence was rising until 1850, and has been declining since then:

http://www.sciencedirect.com/science/article/pii/S0160289611001620

Phenotypic IQ is still increasing, due to the Flynn Effect. But this is rather not related to genes, only to environment.

Quote:

In this study the pattern of temporal variation in innovation rates is examined in the context of Western IQ measures in which historical genotypic gains and losses along with the Flynn effect are considered. It is found that two alternative genotypic IQ estimates based on an increase in IQ from 1455 to 1850 followed by a decrease from 1850 to the present, best fitted the historical growth and decline of innovation rates (r = .876 and .866, N = 56 decades). These genotypic IQ estimates were found to be the strongest predictors of innovation rates in regression in which a common factor of GDP (PPP) per capita and Flynn effect gains along with a common factor of illiteracy and homicide rates were also included (β = .706 and .787, N = 51 decades). The strongest temporal correlate of the Flynn effect was GDP (PPP) per capita (r = .930, N = 51 decades). A common factor of these was used as the dependent variable in regression, in which the common factor of illiteracy/homicide rates was the strongest predictor (β = − 1.251 and − 1.389, N = 51 decades). The genotypic IQ estimates were significant negative predictors of the Flynn effect (β = −.894 and −.978, N = 51 decades). These relationships were robust to path analysis. This finding indicates that the Flynn effect, whilst associated with developmental indicators and wealth, only minimally influences innovation rates, which appear instead to be most strongly promoted or inhibited by changes in genotypic intelligence.

According to this study innovation rates (inventions per 1 million people) have been declining in Western Civilization since ca. 1850. This has not been noticeable so far, because as long as total population was increasing, absolute number of scientists was increasing. But now, as fertility rates are below replacement level, and genotypic IQ continues to decline, probably progress will slow down.

Also note, that today stupid people reproduce faster than smart people, because they don't go to college/university, and instead they marry before 20 and by 25 they already have several children; while smart people usually still have none by this time.

In the past, before the progress of modern medicine, children mortality was much higher in poor families than in rich families. But today in socialist systems, the state supports poor families with benefits (money of taxpayers), and they also start reproducing early on (because they don't continue education after basic level) and end up like this: single mothers with 15 kids (each with different father perhaps! ), whose existence is sustained only by taxpayer money because their parents don't work / contribute to the economy:

"Somebody needs to pay for my 15 kids" (and she is just 37 years old, so still can make a dozen more!):

https://www.youtube.com/watch?v=3anuIAgJmys

 

[Maciamo]

This contradicts the findings of John Hajnal, who found that areas with higher parental age at offspring conception (North-Western and Central Europe) were developing faster. And other researchers also linked higher average paternal (as well as maternal) age at offspring conception with gradually rising average levels of IQ during the Middle Ages and the Early Modern Era.

This might also explain the difference of few points in average IQ scores between Poland and Western Ukraine. The book linked below (in Polish; about family structures in Pre-Modern Poland) on pages 17-20 explains that in regions such as Mazovia and Lesser Poland people were marrying relatively late (women after 23 years of age, men after 26 or after 27 years of age), while in regions such as Red Ruthenia (present-day Western Ukraine) people were marrying early (around 18-19 years of age for both sexes):

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

Eastern boundary between late marriage culture & early marriage culture more or less corresponded to this yellow line:

https://hbdchick.files.wordpress.com/2012/02/extent-and-spread-of-manorialism.jpg?w=460&h=455

I really, really don't think that teenage marriages are good for humanity from evolutionary perspective.

Very interesting. I hadn't noticed the geographical split within Europe between regions where people traditionally marry early vs late. It's amazing how well it matches the modern GDP per capita. The only exceptions are Scotland, Ireland and Wales, but the map appears to be wrong for Scotland. According to Western European marriage pattern on Wikipedia, Lowland Scotland saw patterns similar to England, and their map place also Highland Scotland and Wales in the high age range.

Ireland was traditionally poorer than Britain until US companies starting investing massively in the past few decades. Now the average age at first marriage in Ireland is 31.5 years old for women and 33 for men, is the highest for both genders combined in Europe outside Scandinavia.

Countries that remained poor, like Belarus, Russia, Ukraine, Moldova, Macedonia and Albania, still have the lowest ages at first marriage. So the question is whether people in richer countries get married later, or if, as you postulated, later marriages has a eugenic effect that benefits society and make countries richer. It's important not to confuse cause and effect. The case of Ireland would suggest that people first get richer, then get married older. So it's not because children have older parents that they get higher IQ or increased productivity. It's simply the result of increased prosperity.

The area on the map with the high age of marriage also match the area of Germanic influence in Europe since the Middle Ages. All these regions, except southwest France and north-central Spain (former Visigothic kingdom), happen to have over 5% of Germanic Y-DNA. I am not sure there is really any reliable data on regional disparities for the traditional age of marriage within France and Spain though.

Another way of looking at it is that regions with late marriage and higher GDP per capita have higher Northwest European admixture, and that regions with young marriage and lower GDP per capita have higher Neolithic farmer ancestry.

The two maps don't match up perfectly, but if we make the difference Neolithic ancestry and Northwest European ancestry, regions with higher Northwest European ancestry also happen to be the richer ones.

 

[Tomenable]

Yes many things appear to correlate, but correlation is not always causation.

This is a nice website with various kinds of economic etc. data since year 1800:

http://www.gapminder.org

Click "Gapminder World" for historical data on wealth and health since 1800:

http://www.gapminder.org/data/

I found the case of North Korea vs. South Korea development simply striking:

GDP/capita PPP$ inflation-adjusted in 2015:

South Korea ---- 34,640 $
North Korea ---- 1,390 $

South Korea has 25-times higher GDP per capita than North Korea!

I doubt that genetic differences between North & South Koreans have anything to do with this.

But then you have cases such as for example the "Asian Tigers" versus Sub-Saharan countries.

An excerpt from "The Bleeding Continent..." by Venatius Chukwudum Oforka (link):

https://books.google.pl/books?id=ZZ...r about one-seventieth of that amount&f=false

"(...) When Zambia became independent in 1964, Zambians were, on average, twice as wealthy as the South Koreans. By the turn of the century, South Koreans have become, on average, twenty-seven times richer than the Zambians. Again, thirty years ago, Singapore and Kenya were just about equally poor. Today Singaporeans earn an average of about 24,000 pounds a year, while the average Kenyan earns about 340 pounds a year or about one-seventieth of that amount. (...)"

But on the other hand North Koreans are 25-times (see above) poorer than South Koreans.

Which means that they are about as poor as Zambians (who are 27-times poorer than SKs).

 

[Angela]

Tomenable:
This contradicts the findings of John Hajnal, who found that areas with higher parental age at offspring conception (North-Western and Central Europe) were developing faster. And other researchers also linked higher average paternal (as well as maternal) age at offspring conception with gradually rising average levels of IQ during the Middle Ages and the Early Modern Era.

You're comparing disparate things. The paper is investigating the increasing accumulation of deleterious mutations with paternal age at conception. There's no doubt that this happens from what I can see. There's an extensive citation list at the end of the paper. You should take a look at it.

The Hajnal line theory is something completely different. It has to do with the declining fertility in certain parts of Europe through a combination of late marriage and high rates of celibacy particularly for women.

For those unfamiliar with it.
https://en.wikipedia.org/wiki/Hajnal_line

Where did you get your map, by the way? I haven't seen any that have the line that far east. Most of them look like this, with at least half of Poland being east of the line.

A more modern examination of it in a mega data study can be found here:
http://eml.berkeley.edu/~webfac/eichengreen/Dennison.pdf

The most persuasive explanation of it I've found is a connection to the manorial system.

I think it's clear how this could be of benefit economically in certain circumstances. I've mentioned quite a few times that I saw the operation of this in real life in my own area. Land, especially fertile land, was scarce, whether you owned your own land or rented it from a landlord. In the latter case, it was a form of sharecropping. Upon the death of the tenant, to whom would the landlord give the lease? Through tradition, it was usually given to the "family", but to which man? Obviously, it would go to the strongest, the most capable and intelligent. Other intelligent siblings might go into the priesthood or the convent and some boys might engage in trading or join the army. The rest stayed as unpaid labor on the farm. Family control was strict. No daughter would be given to a man who didn't have land to farm or a decent job.

What the authors are investigating, as I said, is something completely different. They are investigating, in effect, infant and child mortality based on paternal age.

There are all other kinds of studies based on congenital birth defects by area which I've seen, but paternal age at conception is only one factor; there are all kinds of environmental possibilities as well, including rates of alcoholism, lack of nutrition etc.

"The effects of paternal age on offspring are not yet well understood and are studied far less extensively than the effects of maternal age.^[61] Fathers contribute proportionally more DNA mutations to their offspring via their germ cells than the mother, with the paternal age governing how many mutations are passed on. This is because, as humans age, male germ cells acquire mutations at a much faster rate than female germ cells.^[6][7][22]
Around a 5% increase in the incidence of ventricular septal defects, atrial septal defects, and patent ductus arteriosus in offspring has been found to be correlated with advanced paternal age. Advanced paternal age has also been linked to increased risk of achondroplasia and Apert syndrome. Offspring born to fathers under the age of 20 show increased risk of being affected by patent ductus arteriosus, ventricular septal defects, and the tetralogy of Fallot. It is hypothesized that this may be due to environmental exposures or lifestyle choices.^[61]
Research has found that there is a correlation between advanced paternal age and risk of birth defects such as limb anomalies, syndromes involving multiple systems, and Down's syndrome.^[6][22][62] Recent studies have concluded that 5-9% of Down's syndrome cases are due to paternal effects, but these findings are controversial.^{[6][19][22][63]}
There is concrete evidence that advanced paternal age is associated with the increased likelihood that a mother will suffer from a miscarriage or that fetal death will occur.[6]"

https://en.wikipedia.org/wiki/Congenital_disorder

Map of congenital anomalies per 100,000 in 2004

I think it should also be kept in mind that very young age in the mother, and even in some cases in fathers, has also been shown to have deleterious effects. That may be one factor, in addition to close cousin marriage, for the feebleness of many offspring of aristocratic families, since the girls were often married off very young.

Someone also claims to have found a correlation between mean within country IBD rates and the Hajnal line.

 

[Angela]

You're comparing disparate things. The paper is investigating the increasing accumulation of deleterious mutations with paternal age at conception. There's no doubt that this happens from what I can see. There's an extensive citation list at the end of the paper. You should take a look at it.

The Hajnal line theory is something completely different. It has to do with the declining fertility in certain parts of Europe through a combination of late marriage and high rates of celibacy particularly for women.

For those unfamiliar with it.
https://en.wikipedia.org/wiki/Hajnal_line

Where did you get your map, by the way? I haven't seen any that have the line that far east. Most of them look like this, with at least half of Poland being east of the line.

A more modern examination of it in a mega data study can be found here:
http://eml.berkeley.edu/~webfac/eichengreen/Dennison.pdf

The most persuasive explanation of it I've found is a connection to the manorial system.

I think it's clear how this could be of benefit economically in certain circumstances. I've mentioned quite a few times that I saw the operation of this in real life in my own area. Land, especially fertile land, was scarce, whether you owned your own land or rented it from a landlord. In the latter case, it was a form of sharecropping. Upon the death of the landlord, to whom would the landlord give the lease? Through tradition, it was usually given to the "family", but to which man? Obviously, it would go to the strongest, the most capable and intelligent. Other intelligent siblings might go into the priesthood or the convent and some boys might engage in trading or join the army. The rest stayed as unpaid labor on the farm. Family control was strict. No daughter would be given to a man who didn't have land to farm or a decent job.

What the authors are investigating, as I said, is something completely different. They are investigating, in effect, infant and child mortality based on paternal age.

There are all other kinds of studies based on congenital birth defects by area which I've seen, but paternal age at conception is only one factor; there are all kinds of environmental possibilities as well, including rates of alcoholism, lack of nutrition etc.

"The effects of paternal age on offspring are not yet well understood and are studied far less extensively than the effects of maternal age.^[61] Fathers contribute proportionally more DNA mutations to their offspring via their germ cells than the mother, with the paternal age governing how many mutations are passed on. This is because, as humans age, male germ cells acquire mutations at a much faster rate than female germ cells.^[6][7][22]
Around a 5% increase in the incidence of ventricular septal defects, atrial septal defects, and patent ductus arteriosus in offspring has been found to be correlated with advanced paternal age. Advanced paternal age has also been linked to increased risk of achondroplasia and Apert syndrome. Offspring born to fathers under the age of 20 show increased risk of being affected by patent ductus arteriosus, ventricular septal defects, and the tetralogy of Fallot. It is hypothesized that this may be due to environmental exposures or lifestyle choices.^[61]
Research has found that there is a correlation between advanced paternal age and risk of birth defects such as limb anomalies, syndromes involving multiple systems, and Down's syndrome.^[6][22][62] Recent studies have concluded that 5-9% of Down's syndrome cases are due to paternal effects, but these findings are controversial.^{[6][19][22][63]}
There is concrete evidence that advanced paternal age is associated with the increased likelihood that a mother will suffer from a miscarriage or that fetal death will occur.[6]"

https://en.wikipedia.org/wiki/Congenital_disorder

Map of congenital anomalies per 100,000 in 2004

I think it should also be kept in mind that very young age in the mother, and even in some cases in fathers, has also been shown to have deleterious effects. That may be one factor, in addition to close cousin marriage, for the feebleness of many offspring of aristocratic families, since the girls were often married off very young.

Someone also claims to have found a correlation between mean within country IBD rates and the Hajnal line.

View attachment 7640

Razib discusses the paper in his latest blog post, and one of the study authors posts a number of responses.
http://www.unz.com/gnxp/the-cost-of-inbreeding-in-terms-of-health/#comments

Razib's focus was more on the effects of extensive first cousin marriage on genetic fitness, and particularly with regard to Pakistani populations.

 

[Tomenable]

Most of them look like this, with at least half of Poland being east of the line.

The line is schematic, not exact (it is a straight line connecting two points, Trieste with Tallin).

According to this publication (pages 17-18), marriage patterns in Western Poland were the same as in Eastern Poland:

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

The difference was only between Eastern Poland and Western Ukraine (or Red Ruthenia - as it was known back then).

 

[Tomenable]

Most of them look like this, with at least half of Poland being east of the line.

The line is not exact, but schematic (it is a straight line connecting two points - Tallin with Trieste).

According to this publication (pages 17-18), there was no difference in marriage patterns between Western and Eastern Poland:

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

The difference was only on the border between Eastern Poland and Western Ukraine (Red Ruthenia, as it was called back then).

 

[Tomenable]

Most of them look like this, with at least half of Poland being east of the line.

This line is not exact, but schematic (it is a straight line connecting two points - Tallin with Trieste).

According to this publication (pages 17-18), there was no difference in marriage patterns between Western and Eastern Poland:

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

The difference was on the border between Eastern Poland and Western Ukraine (or Red Ruthenia - as it was called back then):

(...) Znacznie bogatsze i oparte na bardziej wiarygodnym materiale źródłowym są badania nad ludnością chłopską już w epoce metrykalnej (XVII i XVIII w.) potwierdzające częściowo hipotezę Hajnala. Kobiety z terenów Śląska, Wielkopolski, Małopolski i Mazowsza zawierały związki małżeńskie późno, właśnie w wieku ok. 23 lat[33], zaś na terenach Rusi Czerwonej zarówno wśród rzymskich, jak i greckich katoliczek typowe było wychodzenie za mąż po osiągnięciu 18-19lat[34]. Wiek zawierania pierwszych małżeństw przez mężczyzn na większości terenów Królestwa Polskiego odpowiadał modelowi opisanemu przez Hajnala, a więc mieli oni przeciętnie co najmniej 26 lat (...)

Translation:

(...) Much richer and based on more reliable source materials are research studies on peasant populations in time periods for which marriage parish records exist (17th and 18th centuries), which partially confirm Hajnal's hypothesis. Women from the regions of Silesia, Greater Poland, Lesser Poland and Mazovia were getting married late, around 23 years of age[33], while in territories of Red Ruthenia both Roman Catholic and Greek Catholic women typically married at 18-19 years of age[34]. The age of first marriage for males in most of the territory of the Kingdom of Poland corresponded to the model described by Hajnal, so they were on average at least 26 years old (...)

If you look at present-day Poland, Lesser Poland = South-Eastern part and Mazovia = North-Eastern part. So in all of present-day Poland (but not of historical Kingdom of Poland, which extended farther east - into modern Ukraine) there were late marriages.

At least that was the case during the 17th - 18th centuries (for earlier centuries sources are less detailed).

Where did you get your map, by the way?

I got it from HBD Chick's blog - the arrows and the yellow line which can be seen there, show the spread and extent of manorialism (which corresponds better to Hajnal Line than does drawing a straight line connecting Trieste with Tallin, as it turns out).

 

[Maciamo]

Thanks for the links, Angela.

The Hajnal line article on Wikipedia explains that, west of the line, nobles married the youngest because they could afford it. Marriages were tied to the economy. "When times were better, more people could afford to marry early and thus have more children and conversely more people delayed marriages (or remained unmarried) and bore fewer children when times were bad". In short, wealthier people had more children, and poor people often couldn't afford to marry at all. If any of you has watched Downtown Abbey, as I am sure many have, you can get an idea of the lot of the servants who either never married or married so late that they ended up not having children.

What is odd with this is that, at the individual level, the older age of marriage was not a sign of higher wealth, but the contrary. Nowadays richer people get married later because they typically study longer and want to advance their career, travel, and have different partners before they settled down. In contrast high school drop-outs have the highest rates of teen pregnancy and early marriage. But until the mid 20th century the trend was reversed.

Nevertheless, at the country level, a high age of first marriage did correlate with higher GDP in past centuries. The richest European countries from the 16th to the 19th century were England and the Low Countries, which also happened to have the highest age of marriage. I don't know how to explain that if poor people married later? High social class disparity?

East of the Hajnal line, people married young and few remained unmarried. This was not because the economy was better in eastern Europe and the Balkans (it wasn't), but because mortality rates were much higher so they couldn't afford not to have high fertility rates.

 

[Tomenable]

In short, wealthier people had more children, and poor people often couldn't afford to marry at all.

It is not so much about the number of children who were born, but rather about how many children actually survived to adulthood (how many lived to reproductive age). Because back then, mortality of babies and children was huge, and especially in poor families most of children were dying before reaching 18 years of age.

Figures from Poland in the 15th - 17th centuries (see the table below) show, that the number of children surviving to adulthood depended on financial status and social class (rich and middle-income peasants had more children surviving to adulthood than poor peasants; rich and middle-income nobles more than poor nobles; etc.):

Table 1. shows that in the 15th century middle-income peasants were just above replacement level (1,1 children per parent) and rich peasants were reproducing faster (1,6 children per parent). Data for poor peasants is not given here, but they had sub-replacement fertility rates (lower than those of middle-income peasants):

Here similar data for England in the 16th-17th centuries (based on studies of wills), and the pattern was the same:

People with more assets at death, had more children surviving to adulthood (note: this data for England refers to children per couple, not sons per father - so a replacement rate of 2,1 from this chart corresponds to 1,05 from the table posted above):

Quote (and a graph below): "(...) the rich had more surviving children than did the poor. From a study of wills made between 1585 and 1638, he finds that will makers with £9 or less to leave their heirs had, on average, just under two children. The number of heirs rose steadily with assets, such that men with more than £1,000 in their gift, who formed the wealthiest asset class, left just over four children. (...)"

That was also the case among Ashkenazi Jews. For example one study of the Jewish District in the town of Brody from 1764 showed, that Jewish homeowner households had 1.2 children per adult member, while Jewish tenant households had only 0.6.

 

[Tomenable]

If any of you has watched Downtown Abbey, as I am sure many have, you can get an idea of the lot of the servants who either never married or married so late that they ended up not having children.

Data on servants as percentage of the total population by region in the Polish-Lithuanian Commonwealth:

http://homoeconomicus.uwb.edu.pl/pdf/Struktury_demograficzne.pdf

======================

When it comes to that study which I mentioned in post #4:

https://www.gwern.net/docs/algernon/2012-woodley.pdf

https://lesacreduprintemps19.files.wordpress.com/2013/05/were-the-victorians-smarter-than-us.pdf

 

[Maleth]

It is not so much about the number of children who were born, but rather about how many children actually survived to adulthood (how many lived to reproductive age). Because back then, mortality of babies and children was huge, and especially in poor families most of children were dying before reaching 18 years of age.

......it was common all over europe and probably all over the world. All has to do with hygiene and nutrition. Rich people had more of both as they could afford it, besides being able to pay for what ever medicine was available during that time.

 

[Tomenable]

Deleted, double post.

 

[Tomenable]

Children of older fathers tend to live longer and age slowly - because they have longer telomeres:

http://www.techtimes.com/articles/4...ildren-genetic-mutation-research-confirms.htm

"Children of older dads albeit less attractive, however, are likely to live longer than their counterparts with younger fathers. Lee Smith, a geneticist at Edinburgh University said that research found that children of older men tend to have longer telomeres, a compound structure at the end of the chromosomes that are associated with longevity."

But they are 5-10% less attractive (for example instead of 10/10 they will be 9,5/10 - not a big deal):

"Someone born to a father of 22 is 5-10 per cent more attractive than those with a 40-year-old father."

 

[LeBrok]

Children of older fathers tend to live longer and age slowly - because they have longer telomeres:

http://www.techtimes.com/articles/4...ildren-genetic-mutation-research-confirms.htm

"Children of older dads albeit less attractive, however, are likely to live longer than their counterparts with younger fathers. Lee Smith, a geneticist at Edinburgh University said that research found that children of older men tend to have longer telomeres, a compound structure at the end of the chromosomes that are associated with longevity."

But they are 5-10% less attractive (for example instead of 10/10 they will be 9,5/10 - not a big deal):

"Someone born to a father of 22 is 5-10 per cent more attractive than those with a 40-year-old father."

Obviously longer telomeres makes people ugly. They should do this experiment again.

 

[Angela]

Obviously longer telomeres makes people ugly. They should do this experiment again.

It's absolutely amazing what some journals will publish nowadays.

This "attractiveness" conclusion is an experiment based on the subjective judgments of 12 people.

At least they did mention in a passing reference the fact that the children of older fathers are more prone to autism and schizophrenia.

As for longevity nowadays, given modern medicine in the western world, children survive who never would have in the past.

 

[Tomenable]

the children of older fathers are more prone to autism

Maciamo had some good threads about Aspies:

http://www.eupedia.com/forum/thread...t-least-some-Asperger-traits?highlight=autism

http://www.eupedia.com/forum/search.php?searchid=1947353