It was the physicist and Nobel laureate Max Planck. He expressed the idea in his 1936 autobiography:
“A new scientific truth does not triumph by convincing its opponents… but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
Great article, very interesting information I didnt know about.
The most surprising by far is the Engels piece of knowedge which made me appreciate him a bit more and justified my thought that he was the best "communist" thinker of them all.
Engels, like Marx, is seen through the lens of events in the following century. Yet those events would have likely happened anyway. There would have been a revolution in Russia, and it would have been no less violent or catastrophic.
I’m not a Marxist, but I find myself moving closer to Marxism. The Cold War kept capitalism honest. Without an opposing ideology, capitalism is starting to show its worst features.
I think Marx can also be seen through the lense of his life, where he never held down a stable job and rode the financial tails of other people, notably Engels who inherited factories from his father and tried to keep them running while also trying to apply his theories towards the workers.
The revolution might have still happened but the Bolsheviks winning could have not happened or been replaced by a healthier ideology.
I agree with the Cold War theory, capitalism unchecked by forces that keep it honest to its doctrine of free markets and competition is not good.
When it comes to economic doctrine, I still see Marxism as a failure and unapplicable to reality notably because of centralized production and the pricing issue.
With regard to your last point, there is no single answer that applies equally to all human societies.
A high-trust society will require less state intervention than a low-trust one. In the latter case, the marketplace will reward those actors who are more ruthless and more willing to eliminate competitors — not by making a better product but by physically eliminating the competition (through assassination, firebombings, extortion, etc.).
This is starting to happen in Canada, and the police are powerless to act. The arsonist doesn't leave a calling card, and the burned-out business is approached by a competitor who offers to buy what's left of it. No actual threat is made. It is simply understood that the arson will continue if the competitor doesn't sell out.
Peter, excellent look into mid-nineteenth-century beliefs about the evolution of intelligence. Thanks.
As you know, you and I have differing opinions on the wisdom of or benefit from genetic enhancement of positive traits, intelligence being one of them. I think we both agree that there has been an overall decrease in intelligence starting around the beginning of the nineteenth century. I also believe we both agree that the decrease in intelligence does not bode well for the ascent of humanity. Other than genetic enhancement, what do you see as a viable event or process to increase human intelligence?
One viable event would be an end to mass immigration. This would kill several birds with one stone.
- The pressure of immigration is coming mainly from societies that are not only lower in mean IQ but also lower in social trust and higher in personal violence.
- Indirectly, it's also depressing the fertility rate by raising the cost of housing. Young people are staying longer with their parents and postponing their plans for marriage and family formation.
- Prospective parents are also having to spend money on private schools because they don't want their kids to be bullied or sexually harassed in the public system. This is having the effect of reducing family size.
A second viable event would be to prohibit employers from making a college or university degree a prerequisite for employment. In exchange, they would be free to use IQ tests to screen prospective applicants. As a result, young adults could enter the workforce at an earlier age and marry earlier. This prohibition could be waived for certain skilled jobs, but the onus would be on the employer to demonstrate that a college/university degree is absolutely necessary.
A third viable event would be a radical overhaul of higher education. Such education would be confined to three purposes: (1) periodic retraining of people who are already in the workforce; (2) intellectual debate and learning for people who are genuinely interested in debate and learning; and (3) research.
Peter, thanks for your reply. I agree with all of your viable events, but they all suffer from the time to viable results and/or efficacy. As you may imagine, I still prefer the elective genetic enhancement, but in conjunction with your three viable events.
If we can halt mass immigration, time will no longer be a pressing constraint. I believe we should encourage family formation by people who are honest, stable, and productive. We should also allow prenatal screening (as is already the case). Finally, I believe we should fully legalize egg donation and surrogacy (which is partly the case in Canada, and largely the case in the US).
My beef with eugenics is that it becomes overly focused on IQ, with other desirable traits being disregarded.
"My beef with eugenics is that it becomes overly focused on IQ, with other desirable traits being disregarded."
Yes, that would be a terrible mistake; I would not support that. One very important trait is integrity. Intelligence without integrity would be a nightmare.
I always steer clear of the term eugenics because of its connotation from the 1920s and 1930s. I prefer elective genetic enhancement — nothing coerced.
By the same argument, consumer protection laws are a restriction of our agency as consumers. We should be free to decide whether a seller is being dishonest with us.
In addition, "pumping and dumping" is not simply a matter of dishonesty. It also imposes external costs on the rest of us (who have to pick up the bill).
I don't think the analogy holds. Consumer protection laws exist because most people don't have the time or the expertise to determine if a commercial product is safe or not. Society has a collective interest is preventing chemical products from blowing up in someone's face.
In the case of seduction, I would argue that women [and their families] have the ability and, indeed, the responsibility, to take steps to determine whether a guy is a decent suitor or a degenerate cad. If women and/or their families fail to take such steps, then I don't see why they should not bear as much responsibility for the outcome as the cad himself.
In practice, the responsibility is borne by the taxpayer. In theory, the seducer can be sued for child support but this is often impossible because (a) he doesn't have the means to pay or (b) he is impossible to locate.
In some cases, the woman is afraid to identify the man. (I know of such cases).
If changes can occur relatively fast via gene-culture coevolution… Should we interpret that as there being some hope that e.g. sub-Saharan Africa may to some extent catch up with more developed corners of the world?
Among Western Europeans, mean IQ increased by three quarters of a standard deviation between the Black Death and the Victorian Era (i.e., c. 1350 and c. 1850). This is about 50-70% of the current difference in mean IQ between Western Europeans and Sub-Saharan Africans.
So “relatively fast” means just that—this evolution has been fast compared to the broad sweep of history.
Will Sub-Saharan Africa catch up over the next seven to ten centuries? Yes, if it enjoys the same economic and social conditions that prevailed in Western Europe during the late medieval and early modern periods. Otherwise, it will take longer.
I don’t know about you, but I probably won’t be around by then.
Peter, here is a possible research direction in social science that seems to be taken rather rarely: the role of parental guidance (usually the father) in offspring mate selection, the lack thereof, and its influence on the downward slope of intelligence. Many generations ago, fathers would strongly 'suggest' the desired qualities in a potential mate for his daughter(s), such as intelligence, integrity, and initiative, and for his son(s), a loving, nurturing mate ( that will tick off the feminists). Those days are bygone for sure. Hollywood has made billions of dollars with the follow your heart in mate selection memes over the decades. It appears to me that one of the reasons for the great success of Ashkenazi Jews was due to parental guidance of offspring mate selection.
In the US and England, but not in Scotland, parents used to have a veto over the marital choices of their children until the age of 21. This veto gradually disappeared from the mid-19th century onward. A veto still exists in the sense that parents can always disinherit their offspring.
I’m more worried about seduction than poor marital choices. Males used to be punished in the US for “pumping and dumping”, either with substantial fines or with jail time.
"Males used to be punished in the US for “pumping and dumping”, either with substantial fines or with jail time."
That is interesting; I did not know that. Would you give some information on that, such as how it was proven? And wouldn't that be a case of poor mate choice?
I'm talking about extramarital sex with no genuine intention to marry.
Seduction was legally recognized in the U.S. from roughly 1848 to the early 20th century, first as a civil action and later, in some states, as a criminal offense. These laws aimed to punish men who obtained sexual access to women through fraud, promises of marriage, or deception.
Across the United States, seduction statutes typically imposed fines, prison terms, marriage as a bar to prosecution, or enhanced penalties for younger victims
The issue is moral, financial, and genetic. Seduced women tend to have children out of wedlock. Someone has to pick up the bill, and it's usually the taxpayer.
Regarding the painting at the top of the page with the two figures in red in the foreground. They look superimposed upon a scene where they don't belong. I was convinced that the painting must have been AI generated but no, it was an actual painting from 1878. How bizarre!
I was interested in the list of men whose ideas might become properly appreciated only after some time has passed. One of those was Michael Woodley of Menie. I think he often collaborated with Edward Dutton. Could Dutton also be included in your list or is he a bit of a loose cannon? I don't mean that unkindly. It's just as an amateur I find it hard to distinguish daring thinker from crank.
I like to feature lesser-known artists from the 19th century; in this case, Giuseppe De Nittis — an Italian surrealist who painted in France and England. I, too, was fascinated by the two figures in red, as well as the numerous heads tilted leftward but never rightward. A hidden message?
I was referring to the authors of several papers that "anticipated" the Reich lab's recent paper. In fact, the authors of the latter were fully aware of this earlier work, but they chose to ignore it in their bibliography. I understand the unstated reasons, but they still committed a serious breach of normal practice.
Edward Dutton has been a target of unwarranted abuse, but no one — to my knowledge —has plagiarized his work.
I see what you mean about the leftward tilt of heads. With the group of men bottom left, craning their necks to read the newspaper seller's headlines is understandable, but also, for no apparent reason, the policeman and the bearded gent bottom right?
I was already familiar with two of di Nittis' works ('Child in the Sun' and 'Westminster Bridge') because when I come across a painting I like, usually on Richard Morris's X account, I put it in my screen saver folder, which is set up to change every minute. That way I get to see all 400 or so paintings I've saved until now. While some are added others that I tire of get deleted. I would say around 95% of the paintings in the folder are from between 1850 - 1950.
Ah, I see what you mean about the group you mentioned. Similar to Steve Sailer in that people read him but no one admits to it or acknowledges where 'their' ideas came from. And I'm glad that Edward Dutton's work isn't frowned upon by either yourself or the group of men you mentioned. I've certainly seen him interview David Pfiffer and Emil Kirkegaard and they all seem to be on the same page.
By definition, a phenotype is a range of possibilities that is permitted by the genotype. For instance, a person may perform different kinds of work, speak different languages, and live with different women. Same genotype, but different phenotypic expressions.
Yes, we are malleable. Infinitely malleable? Please. Has the word "infinitely" lost its original meaning?
As I said above, much of our malleability is simply variation within the bounds of our phenotype. This is how we have adapted to different natural and cultural environments. We push the bounds of our phenotype, and it becomes a template for natural selection — which selects for genetic variants that help us fit the new phenotype with less effort.
So, over successive generations, the new phenotype becomes a new genotype. There are many terms for this process in the scientific literature: genetic assimilation, the Baldwin effect, etc. The key point is that cultural evolution paves the way for genetic evolution. Culture creates a new environment, and we have to adapt to that environment, just as we have to adapt to climate or local food.
As for your ethnographic examples, they reveal a certain degree of exaggeration. My doctoral supervisor was renowned for his research on the third gender among the Inuit. Yet, near the end of his life, he became alarmed by the way his research was being misused for political purposes. He pointed out that Inuit gender is malleable only before puberty. At puberty, boys and girls are expected to assume their biological identity as men and women. This also used to be the rule in Western cultures: boys were often dressed up as girls until the age of 6. Yet those same "trans-girls" would grow up to become men like Ernest Hemingway or Franklin Roosevelt.
"boys were often dressed up as girls until the age of 6."
Yes! That's called "breeching". :-)
Anyway,
It seems, things like Matriarchy/Polyandry or 3rd Gender are not at the "genetic" level. It appears that, rather, something's happened to disturb the 1:1 sex ratio and they ended up with excess males or females...
Meanwhile,
The Yanomami people of the Amazon Rainforest are heavily tilted towards being left-handed (an obvious "genetic" trait), which is, if Ed Dutton is to be believed, a sign that something "wrong" occurred in the brain: "sinistrality", if Ed Dutton is to be believed, correlates with r-selected strategies, low impulse control/aggression and lower-than-average IQ.
P.S.:
I've no PhD in Biology or what-not, I'm self-taught/dilettante, so I'm just trying my best! :-)
More boys are born than girls in all human populations, although the sex ratio at birth is highest in East Asians and lowest in SubSaharan Africans. This might be an adaptation to polygyny. I wrote about this subject in:
Frost, P. (2001). Polygyny and sex ratios. In: V.L. Bullough (ed.), Encyclopedia of Birth Control. Santa Barbara (Cal.): ABC-CLIO, pp. 218-223.
Science also advances one funeral at a time. I forget who said that.
It was the physicist and Nobel laureate Max Planck. He expressed the idea in his 1936 autobiography:
“A new scientific truth does not triumph by convincing its opponents… but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
You beat me to it.
German physicist Max Planck
Great article, very interesting information I didnt know about.
The most surprising by far is the Engels piece of knowedge which made me appreciate him a bit more and justified my thought that he was the best "communist" thinker of them all.
Engels, like Marx, is seen through the lens of events in the following century. Yet those events would have likely happened anyway. There would have been a revolution in Russia, and it would have been no less violent or catastrophic.
I’m not a Marxist, but I find myself moving closer to Marxism. The Cold War kept capitalism honest. Without an opposing ideology, capitalism is starting to show its worst features.
"Without an opposing ideology, capitalism is starting to show its worst features."
Agreed; unfettered capitalism soon manifests as avarice.
I think Marx can also be seen through the lense of his life, where he never held down a stable job and rode the financial tails of other people, notably Engels who inherited factories from his father and tried to keep them running while also trying to apply his theories towards the workers.
The revolution might have still happened but the Bolsheviks winning could have not happened or been replaced by a healthier ideology.
I agree with the Cold War theory, capitalism unchecked by forces that keep it honest to its doctrine of free markets and competition is not good.
When it comes to economic doctrine, I still see Marxism as a failure and unapplicable to reality notably because of centralized production and the pricing issue.
With regard to your last point, there is no single answer that applies equally to all human societies.
A high-trust society will require less state intervention than a low-trust one. In the latter case, the marketplace will reward those actors who are more ruthless and more willing to eliminate competitors — not by making a better product but by physically eliminating the competition (through assassination, firebombings, extortion, etc.).
This is starting to happen in Canada, and the police are powerless to act. The arsonist doesn't leave a calling card, and the burned-out business is approached by a competitor who offers to buy what's left of it. No actual threat is made. It is simply understood that the arson will continue if the competitor doesn't sell out.
"I agree with the Cold War theory, capitalism unchecked by forces that keep it honest to its doctrine of free markets and competition is not good."
Indeed, as I see it.
Peter, excellent look into mid-nineteenth-century beliefs about the evolution of intelligence. Thanks.
As you know, you and I have differing opinions on the wisdom of or benefit from genetic enhancement of positive traits, intelligence being one of them. I think we both agree that there has been an overall decrease in intelligence starting around the beginning of the nineteenth century. I also believe we both agree that the decrease in intelligence does not bode well for the ascent of humanity. Other than genetic enhancement, what do you see as a viable event or process to increase human intelligence?
One viable event would be an end to mass immigration. This would kill several birds with one stone.
- The pressure of immigration is coming mainly from societies that are not only lower in mean IQ but also lower in social trust and higher in personal violence.
- Indirectly, it's also depressing the fertility rate by raising the cost of housing. Young people are staying longer with their parents and postponing their plans for marriage and family formation.
- Prospective parents are also having to spend money on private schools because they don't want their kids to be bullied or sexually harassed in the public system. This is having the effect of reducing family size.
A second viable event would be to prohibit employers from making a college or university degree a prerequisite for employment. In exchange, they would be free to use IQ tests to screen prospective applicants. As a result, young adults could enter the workforce at an earlier age and marry earlier. This prohibition could be waived for certain skilled jobs, but the onus would be on the employer to demonstrate that a college/university degree is absolutely necessary.
A third viable event would be a radical overhaul of higher education. Such education would be confined to three purposes: (1) periodic retraining of people who are already in the workforce; (2) intellectual debate and learning for people who are genuinely interested in debate and learning; and (3) research.
Peter, thanks for your reply. I agree with all of your viable events, but they all suffer from the time to viable results and/or efficacy. As you may imagine, I still prefer the elective genetic enhancement, but in conjunction with your three viable events.
If we can halt mass immigration, time will no longer be a pressing constraint. I believe we should encourage family formation by people who are honest, stable, and productive. We should also allow prenatal screening (as is already the case). Finally, I believe we should fully legalize egg donation and surrogacy (which is partly the case in Canada, and largely the case in the US).
My beef with eugenics is that it becomes overly focused on IQ, with other desirable traits being disregarded.
Great addition points made.
"My beef with eugenics is that it becomes overly focused on IQ, with other desirable traits being disregarded."
Yes, that would be a terrible mistake; I would not support that. One very important trait is integrity. Intelligence without integrity would be a nightmare.
I always steer clear of the term eugenics because of its connotation from the 1920s and 1930s. I prefer elective genetic enhancement — nothing coerced.
Seduction laws imply that women have no agency; that they can't help but go to bed with their seducer.
If women have no agency, then why do we let them make mating decisions at all? Why do we let them obtain higher education? Why do we let them vote?
By the same argument, consumer protection laws are a restriction of our agency as consumers. We should be free to decide whether a seller is being dishonest with us.
In addition, "pumping and dumping" is not simply a matter of dishonesty. It also imposes external costs on the rest of us (who have to pick up the bill).
I don't think the analogy holds. Consumer protection laws exist because most people don't have the time or the expertise to determine if a commercial product is safe or not. Society has a collective interest is preventing chemical products from blowing up in someone's face.
In the case of seduction, I would argue that women [and their families] have the ability and, indeed, the responsibility, to take steps to determine whether a guy is a decent suitor or a degenerate cad. If women and/or their families fail to take such steps, then I don't see why they should not bear as much responsibility for the outcome as the cad himself.
In practice, the responsibility is borne by the taxpayer. In theory, the seducer can be sued for child support but this is often impossible because (a) he doesn't have the means to pay or (b) he is impossible to locate.
In some cases, the woman is afraid to identify the man. (I know of such cases).
If changes can occur relatively fast via gene-culture coevolution… Should we interpret that as there being some hope that e.g. sub-Saharan Africa may to some extent catch up with more developed corners of the world?
Among Western Europeans, mean IQ increased by three quarters of a standard deviation between the Black Death and the Victorian Era (i.e., c. 1350 and c. 1850). This is about 50-70% of the current difference in mean IQ between Western Europeans and Sub-Saharan Africans.
So “relatively fast” means just that—this evolution has been fast compared to the broad sweep of history.
Will Sub-Saharan Africa catch up over the next seven to ten centuries? Yes, if it enjoys the same economic and social conditions that prevailed in Western Europe during the late medieval and early modern periods. Otherwise, it will take longer.
I don’t know about you, but I probably won’t be around by then.
Peter, here is a possible research direction in social science that seems to be taken rather rarely: the role of parental guidance (usually the father) in offspring mate selection, the lack thereof, and its influence on the downward slope of intelligence. Many generations ago, fathers would strongly 'suggest' the desired qualities in a potential mate for his daughter(s), such as intelligence, integrity, and initiative, and for his son(s), a loving, nurturing mate ( that will tick off the feminists). Those days are bygone for sure. Hollywood has made billions of dollars with the follow your heart in mate selection memes over the decades. It appears to me that one of the reasons for the great success of Ashkenazi Jews was due to parental guidance of offspring mate selection.
In the US and England, but not in Scotland, parents used to have a veto over the marital choices of their children until the age of 21. This veto gradually disappeared from the mid-19th century onward. A veto still exists in the sense that parents can always disinherit their offspring.
I’m more worried about seduction than poor marital choices. Males used to be punished in the US for “pumping and dumping”, either with substantial fines or with jail time.
"Males used to be punished in the US for “pumping and dumping”, either with substantial fines or with jail time."
That is interesting; I did not know that. Would you give some information on that, such as how it was proven? And wouldn't that be a case of poor mate choice?
I'm talking about extramarital sex with no genuine intention to marry.
Seduction was legally recognized in the U.S. from roughly 1848 to the early 20th century, first as a civil action and later, in some states, as a criminal offense. These laws aimed to punish men who obtained sexual access to women through fraud, promises of marriage, or deception.
Across the United States, seduction statutes typically imposed fines, prison terms, marriage as a bar to prosecution, or enhanced penalties for younger victims
Sources:
https://time.com/5776805/seduction-law-history/
https://lawdefiner.com/seduction-meaning-in-law/
https://access.heinonline.com/HOL/LandingPage?handle=hein.journals/clr21&div=20&id=&page=
Thanks for the info. This seems like a morality issue.
The issue is moral, financial, and genetic. Seduced women tend to have children out of wedlock. Someone has to pick up the bill, and it's usually the taxpayer.
Seduction laws imply that women have no agency; that they can't help but go to bed with their seducer.
If women have no agency, then why do we let them make mating decisions at all? Why do we let them obtain higher education? Why do we let them vote?
Regarding the painting at the top of the page with the two figures in red in the foreground. They look superimposed upon a scene where they don't belong. I was convinced that the painting must have been AI generated but no, it was an actual painting from 1878. How bizarre!
I was interested in the list of men whose ideas might become properly appreciated only after some time has passed. One of those was Michael Woodley of Menie. I think he often collaborated with Edward Dutton. Could Dutton also be included in your list or is he a bit of a loose cannon? I don't mean that unkindly. It's just as an amateur I find it hard to distinguish daring thinker from crank.
I like to feature lesser-known artists from the 19th century; in this case, Giuseppe De Nittis — an Italian surrealist who painted in France and England. I, too, was fascinated by the two figures in red, as well as the numerous heads tilted leftward but never rightward. A hidden message?
I was referring to the authors of several papers that "anticipated" the Reich lab's recent paper. In fact, the authors of the latter were fully aware of this earlier work, but they chose to ignore it in their bibliography. I understand the unstated reasons, but they still committed a serious breach of normal practice.
Edward Dutton has been a target of unwarranted abuse, but no one — to my knowledge —has plagiarized his work.
I see what you mean about the leftward tilt of heads. With the group of men bottom left, craning their necks to read the newspaper seller's headlines is understandable, but also, for no apparent reason, the policeman and the bearded gent bottom right?
I was already familiar with two of di Nittis' works ('Child in the Sun' and 'Westminster Bridge') because when I come across a painting I like, usually on Richard Morris's X account, I put it in my screen saver folder, which is set up to change every minute. That way I get to see all 400 or so paintings I've saved until now. While some are added others that I tire of get deleted. I would say around 95% of the paintings in the folder are from between 1850 - 1950.
Ah, I see what you mean about the group you mentioned. Similar to Steve Sailer in that people read him but no one admits to it or acknowledges where 'their' ideas came from. And I'm glad that Edward Dutton's work isn't frowned upon by either yourself or the group of men you mentioned. I've certainly seen him interview David Pfiffer and Emil Kirkegaard and they all seem to be on the same page.
Fascinating, Dr Frost!
Keep it going, in both Academia and on The Internet!
I've a question, if I may:
How does an evolutionist respond to egalitarians who cite obscure tribes as so-called "evidence" for "infinite malleability of the brain"?
(Basically, these egalitarians believe the "New Soviet Man" is possible – perhaps, desirable.)
Examples:
Mangaia in the Cook Islands where there's no sexual restraint.
https://en.wikipedia.org/wiki/Mangaia#Culture
The Pirahã people of the Amazon Rainforest whose language is, let's say, very "unique".
https://en.wikipedia.org/wiki/Pirah%C3%A3_language#Color
Tribes in Africa where a Matriarchy rules...
"3rd Gender" conceptions, such as in Thailand...
Etc.
By definition, a phenotype is a range of possibilities that is permitted by the genotype. For instance, a person may perform different kinds of work, speak different languages, and live with different women. Same genotype, but different phenotypic expressions.
Yes, we are malleable. Infinitely malleable? Please. Has the word "infinitely" lost its original meaning?
As I said above, much of our malleability is simply variation within the bounds of our phenotype. This is how we have adapted to different natural and cultural environments. We push the bounds of our phenotype, and it becomes a template for natural selection — which selects for genetic variants that help us fit the new phenotype with less effort.
So, over successive generations, the new phenotype becomes a new genotype. There are many terms for this process in the scientific literature: genetic assimilation, the Baldwin effect, etc. The key point is that cultural evolution paves the way for genetic evolution. Culture creates a new environment, and we have to adapt to that environment, just as we have to adapt to climate or local food.
As for your ethnographic examples, they reveal a certain degree of exaggeration. My doctoral supervisor was renowned for his research on the third gender among the Inuit. Yet, near the end of his life, he became alarmed by the way his research was being misused for political purposes. He pointed out that Inuit gender is malleable only before puberty. At puberty, boys and girls are expected to assume their biological identity as men and women. This also used to be the rule in Western cultures: boys were often dressed up as girls until the age of 6. Yet those same "trans-girls" would grow up to become men like Ernest Hemingway or Franklin Roosevelt.
https://www.anthro1.net/p/adieu-bernard-1936-2025
"boys were often dressed up as girls until the age of 6."
Yes! That's called "breeching". :-)
Anyway,
It seems, things like Matriarchy/Polyandry or 3rd Gender are not at the "genetic" level. It appears that, rather, something's happened to disturb the 1:1 sex ratio and they ended up with excess males or females...
Meanwhile,
The Yanomami people of the Amazon Rainforest are heavily tilted towards being left-handed (an obvious "genetic" trait), which is, if Ed Dutton is to be believed, a sign that something "wrong" occurred in the brain: "sinistrality", if Ed Dutton is to be believed, correlates with r-selected strategies, low impulse control/aggression and lower-than-average IQ.
P.S.:
I've no PhD in Biology or what-not, I'm self-taught/dilettante, so I'm just trying my best! :-)
More boys are born than girls in all human populations, although the sex ratio at birth is highest in East Asians and lowest in SubSaharan Africans. This might be an adaptation to polygyny. I wrote about this subject in:
Frost, P. (2001). Polygyny and sex ratios. In: V.L. Bullough (ed.), Encyclopedia of Birth Control. Santa Barbara (Cal.): ABC-CLIO, pp. 218-223.