Saturday, December 26, 2020

Frank Salter and the National Question


When did the interests of our elites begin to diverge from ours? (Wikicommons)


Kinship ties have historically been weak among Europeans north and west of a line running from Trieste to St. Petersburg. Within that area, and going back at least a millennium, almost everyone would be single for at least part of adulthood, with many staying single their entire lives. In addition, children usually left the nuclear family to form new households, and many individuals circulated among unrelated households, typically young people sent out as servants.


This marriage pattern is associated with an equally unusual behavioral pattern: stronger individualism; weaker loyalty to kin; and greater willingness to trust strangers. These tendencies have a psychological basis. Affective empathy is not expressed primarily within intimate relationships, as between a mother and her child. Instead, it is extended to everyone, unless that person is judged to be a moral outcaste. Morality itself is less situational and more universal—absolute rules that apply equally to everyone. Finally, the ability to internalize that kind of morality is stronger, as are the feelings of guilt you experience when breaking a rule—even if you are the sole witness to your misdeed.


Some say the "Western European Marriage Pattern" began with Western Christianity—what would become Roman Catholicism and, later, Protestantism. By forbidding cousin marriages and by framing morality in terms of universal rules, the Western Church laid the basis for a new civilization (Schulz et al. 2019). Others say this pattern goes farther back in time; the Western Church thus assimilated pre-existing social norms from its northwest European converts (Frost 2017; Frost 2020).


Whatever the cause, northwest Europeans possess a behavioral package that has helped them create larger social networks independently of kinship. One example is the market economy. Keep in mind the distinction between "market economy" and "markets." The latter are as old as history, and yet for most of history they were little more than marketplaces—pockets of economic activity limited in time and space, incapable of becoming the main organizing principle of society. That role was filled by kinship. Production of goods for a market was secondary to the reproduction of life for one’s family and kin group.


The market economy did not originate in the markets of Greece and Rome. It ultimately goes back to the North Sea communities of the seventh century. There, trade underwent a sustained expansion that would in time eclipse trade on the Mediterranean, eventually creating the current global economy (Callmer 2002, see also Barrett et al. 2004).  


Greer (2013a, 2013b) pinpoints the fourteenth century as the time when the North Sea economies began to outpace the rest of the world:


[...] the two exceptions are Netherlands and Great Britain. These North Sea economies experienced sustained GDP per capita growth for six straight centuries. The North Sea begins to diverge from the rest of Europe long before the 'West' begins its more famous split from 'the rest.'


[...] we can pin point the beginning of this 'little divergence' with greater detail. In 1348 Holland's GDP per capita was $876. England's was $777. In less than 60 years time Holland's jumps to $1,245 and England's to 1090. The North Sea's revolutionary divergence started at this time. (Greer 2013b; see also Greer 2013a and Hbd *chick 2013)


The rise of the West is usually attributed to things like the European conquest of the Americas, the invention of printing, the creation of modern financial institutions, the Atlantic slave trade, and the Protestant Reformation. Yet the West was already rising before any of that happened. The ultimate cause was behavioral: the West was better at exploiting the market concept because it could extend the sphere of high trust far beyond small groups of closely related individuals.


The rest is ... history. The market economy grew and grew and grew. Initially, its main vehicle was the nation-state; the nations of northwest Europe thus became fierce rivals for commercial dominance. Only later would the market economy be freed of that vehicle. When exactly? At the dawn of the twentieth century, when the elite of the British Empire became fully global in its ambitions? After the two world wars, which left the United States as the dominant power in the global market? During the 1980s, when offshoring of jobs got into full swing?


The liquidation of the nation-state was a process, not a point in time. Over the twentieth century our national elites went global and lost any loyalty they once had to the old working class of the West, eventually viewing it as an anachronism. After weighing the costs and benefits, they concluded it should be replaced with cheaper labor from other sources. The old working class has thus been caught in a vice. On the one hand, high-paying jobs are outsourced to low-wage countries; on the other hand, low-wage labor is insourced for those jobs that cannot be outsourced, typically in services and construction. The result? Non-elite individuals have seen their wages stagnate throughout the West, particularly in the United States. And the peoples of the West are being progressively replaced, even in their ancestral homelands.


Well, so what? Yes, they created the concept of the market economy, but that concept no longer belongs exclusively to them and no longer requires their existence. So why should they continue to exist?


That question has two answers. First, the market economy isn't just a concept. It is also certain ways of being and doing. As northwest Europeans dwindle away and eventually disappear, there will be a shift toward behaviors and mindsets that prevail elsewhere. People will become less trusting of each other, and less sure about what they pay for. Transactions will have to be checked and double-checked, and many will no longer be worth the bother. To keep the market economy from collapsing, governments will become increasingly authoritarian and adopt Orwellian levels of surveillance. Like China, but not as nice.


The second answer is existential. It's the answer that explains every living thing on this planet. We were. We are. We will be. Existence is not justified by argument. It is justified by an act of will.



Frank Salter and the National Question


Frank Salter is an Australian political scientist who is probably best known for his book On Genetic Interests: Family, Ethnicity and Humanity in an Age of Mass Migration (2003). In a recent speech, he has argued for a new balance between the market economy and our need for kinship. This balance would be provided by “national liberalism,” as defined by the nineteenth-century thinker John Stuart Mill:


Where the sentiment of nationality exists in any force, there is a prima facie case for uniting all the members of the nationality under the same government, and a government to themselves apart [...] One hardly knows what any division of the human race should be free to do if not to determine with which of the various collective bodies they choose to associate themselves.


This twinning of nationalism with liberalism was common during the nineteenth century. Liberals saw the nation-state as a means to emancipate the individual from the confines of local and regional identities. France was the go-to model. Originally, its people mostly spoke various regional languages; only a minority could speak French. Even the laws differed from one part of the country to the other. After the Revolution, a uniform language was imposed through the schools, and the laws too were made uniform. Individuals could now freely circulate and express themselves within a much larger territory. There were also economic benefits: economies of scale, labor mobility, and a more rational distribution of the factors of production.


That logic, however, didn't stop with the nation-state. It eventually led to globalism. We like to see globalism as a healthy reaction to the sins of nationalism, particularly the two world wars, yet nationalism was already morphing into globalism before 1914. Look at John Stuart Mill's country. In the early nineteenth century it was, arguably, a nation-state. Most people under British rule were of British origin and shared the same language, culture, and life-ways. When the century came to an end, all of that had changed: the British were now a minority within a vast multinational empire. The country no longer served its people as a vehicle for their survival. It now served an increasingly globalist elite.


As Frank Salter points out, nationalism can be diverted into post-national channels. Modern techniques of propaganda can create an artificial feeling of kinship that serves elite interests:


... investment in ethnic kin carries risks due to reliance on culture, which is more prone to error than the instinct-laden bonds of family. In his book, Imagined Communities, the Marxist historian Benedict Anderson argued convincingly that national communities are perceived indirectly through cultural channels, such as stories, books, films, press reports, memorials, and so on. The same goes for events that are perceived to enhance or threaten the nation. The sense of fellowship can be extended through cultural devices to elicit bonding with hypothetical kin. Likewise, the realm of antagonisms, of distrust, hatred and combat, can be hugely inflated in scope and intensity in the ethnocentric mind. (Salter 2020)


The risks are obvious. The national elite may pursue its self-interest to the detriment of the nation it supposedly serves. Instead of using its cultural dominance to promote common national aims, it may manipulate the nation’s culture to further its own post-national and supra-national ambitions.





Barrett, J.H., Locker, A.M. and Roberts, C.M. (2004). Dark Age Economics revisited: The English fish bone evidence AD 600-1600. Antiquity 78 (301): 618-636.


Callmer, J. (2002). North-European trading centres and the early medieval craftsman. Craftsmen at Åhus, North-Eastern Scania, Sweden ca. AD 750-850+, UppSkrastudier 6 (Acta Archaeologica Lundensia Ser. in 8, no. 39), 133-158.


Frost, P. (2017). The Hajnal line and gene-culture coevolution in northwest Europe. Advances in Anthropology 7: 154-174.  


Frost, P. (2020). The large society problem in Northwest Europe and East Asia. Advances in Anthropology 10(3): 214-134.   


Greer, T. (2013a). The Rise of the West: Asking the Right Questions. July 7, The Scholar's Stage  


Greer, T. (2013b). Another look at the 'Rise of the West' - but with better numbers. November 20, The Scholar's Stage   


Hbd *chick (2013). Going Dutch, November 29


Salter, F. (2020).  Sir Henry Parkes's liberal-ethnic nationalism. Sydney Trads, December 18  


Schulz, J.F., D. Bahrami-Rad, J.P. Beauchamp, and J. Henrich. (2019). The Church, intensive kinship, and global psychological variation. Science 366(707): 1-12.


Saturday, December 19, 2020

Brain size and family structure in Estonia


Estonian schoolchildren (Wikicommons). Estonian children have smaller brains if raised by a biological parent and a step-parent. Therefore, two committed parents are better than one, right? Well, not in this case. Brains aren't smaller in Estonian children raised by a single parent (and no step-parent).



In Estonia, cranial volume was one of several anthropometric traits that were routinely measured in schoolchildren during the Soviet era. The data didn't suffer from volunteer bias because the measurements were mandatory. Mortality bias was minimal because the subjects were young. This data source is thus better in many respects than data from Western biobanks. It is now being mined by Peeter Hõrak, a University of Tartu professor, to learn more about nature and nurture in human brain development.


I discussed this data source in a previous post (Frost 2020). One problem is that the study population is not as homogeneous as it may seem. In fact, 16% of the fathers and 7% of the fathers were not Estonian (Hõrak 2020). This factor might explain some differences in the data, especially changes over time.



The latest study


This data source has now been used to see whether the brain size of children is influenced by family structure, specifically whether the child was raised by biological parents or by step-parents. The data came from 822 children born between 1980 and 1987 in Tartu, Estonia and were measured at around 14 years of age.


The children had significantly larger brains when the household had both biological parents:

Cranial volume was related to family structure and paternal education. Children living with both birth-parents had larger heads than those living in families containing a step-parent. [...] our findings suggest that families including both genetic parents provide non-material benefits that stimulate predominantly cranial growth. (Lauringson et al. 2020)


That's what we read in the Abstract. The brain was bigger on average in children who had been raised by both biological parents, rather than by a biological parent and a step-parent, presumably because a step-parent contributes less to the child's upbringing.


That finding is rejected, however, in the Results section. It turns out that there was no difference in brain size between children raised by both biological parents and children raised by a single parent (in almost all cases the biological mother). The brain was smaller only in children raised by a biological parent and a step-parent:


At the same time, cranial volumes of children living with a single parent were similar to those living with two providers, even though the former reported on average lower resource availability and more frequent meat shortage. Associations between family type and cranial volume thus cannot be explained on the basis of dilution of material resources. (Lauringson et al. 2020)

Differences in family structure also failed to correlate with differences in the child's height. If life in a stepfamily had somehow harmed the child's development, that harm was much less observable in overall body growth than in cranial volume.


So what's going on here? Keep in mind two things about Estonian society of the late 20th century:


- A single parent was almost always a woman, often a widow who refused to remarry, either because she still felt attached to her deceased spouse or because she considered the potential husbands available to be more trouble than they were worth.


- A step-parent could be of either sex. A stepfather often took over from a man who had sired the child out of wedlock or during a short-lived marriage.


Thus, on average, the biological father was a different kind of man in the two situations. In the first situation, he was usually the sort of man who would remain with the mother of his child until his death. In the second, he was often the sort of man who would leave the mother of his child once a more interesting woman came into view. One may presume there are differences in genetic quality between the two kinds of men. This hypothesis is actually advanced in the study:


An alternative (yet not mutually exclusive) explanation to the observed associations between family type and cranial volume of children would be that parents prone to remarrying possess on average (genetically) smaller heads than those prone to avoiding divorce or remaining single after divorcing. Such a scenario would assume robust genetic correlations between cranial volume and personality traits related to marriage stability. Twin studies have shown that genetic factors account for 13-53% of the variation in divorce [...], and if personality traits associated with a propensity to divorce are genetically correlated with cranial volume or its growth rate, one would detect smaller heads of children growing up in divorced/separated families. Such an explanation would be consistent with the predictions of life history theory, assuming that qualities characteristic of slow pace of life-including high somatic investment into body and brain growth and propensity for relatively low mating effort (in relation to parenting effort)-have coevolved (and cluster) with higher mental abilities and conscientious and risk-averse personality traits [...]. Consistent with this view are also the findings in our sample where fathers with only primary education were shorter and more prone to divorce/separate than others. (Lauringson et al. 2020)


We see a similar problem of interpretation with the relationship between father absence and early sexual maturity in daughters. Using a large sample of 1,247 daughters, Surbey (1990) found that daughters with an absent father matured four to five months earlier than those who lived with both parents continuously and seven months earlier than those with an absent mother. Surbey argued that the presence of a strange male accelerates the speed of sexual maturation. In other words, at a subconscious level, the girl does not recognize the man as a father. She recognizes him as a potential mate, and her body gears up for procreation.


This hypothesis was challenged by Mendle et al. (2006) who examined the daughters of twin mothers.


In a pair of twin mothers of which only one raises her children with a stepfather, the offspring of both twins are equally likely to display early age of menarche. It therefore appears that some genetic or shared environmental confound accounts for the earlier association found in female children living with stepfathers.


It seems, then, that people who end up as step-parents are, on average, genetically different from other parents. They tend to have the mental and behavioral characteristics of a "fast" life history.





Frost, P. (2020). Declining intelligence in the 20th century: the case of Estonia. Evo and Proud, August 3


Hõrak, P. (2020). Personal communication.


Lauringson, V., G. Veldre, and P. Hõrak. (2020). Adolescent Cranial Volume as a Sensitive Marker of Parental Investment: The Role of Non-material Resources? Frontiers in Psychology 15 December


Surbey, M.K. (1990). Family composition, stress, and the timing of human menarche. In T.E. Ziegler & F.B. Bercovitch (eds.) Socioendocrinology of Primate Reproduction, pp. 11-32, New York: Wiley-Liss Inc.

Tuesday, December 8, 2020

Large differences at a few genes?

By equalizing the environment, socialist regimes made genetic influences more noticeable (Wikicommons).



Current thinking is that cognitive ability differs from one person to the next through small differences at very many genes.  This view is stated in a recent review of the genetics of intelligence:


It became clear that the problem was power: the largest effect sizes of associations between individual single-nucleotide polymorphisms (SNPs) and intelligence were extremely small, accounting for less than 0.05% of the variance of intelligence. The average effect size of the tens of thousands of SNPs needed to explain the 50% heritability of intelligence is of course much lower. If the average effect size is 0.005%, 10,000 such SNP associations would be needed to explain the 50% heritability of intelligence. (Plomin and von Stumm 2018)


This view is not shared by IQ researcher Volkmar Weiss, who argues that a few genes have variants that differ more substantially in their effects. Fortuitous combinations of such variants may explain the births of exceptionally intelligent individuals to above-average parents:


The possibility of rapid social ascent and descent suggests that the differences in thinking power, the IQ, are based on a simple genetic polymorphism, which prevents the solidification of society. A broad middle class, which marries upwards or downwards or among itself, connects the social extremes. The data supports it: The children of this middle class have a 25% chance of becoming part of the intellectual elite, 25% chance of belonging to the mentally healthy working class and a 50% chance of maintaining the social status of their parents. (Weiss 2020, p. 14)


Consequently, "in each generation the greatest number of highly gifted people do not come from marriages between highly gifted people, but from marriages of the middle class" (Weiss 2020, p. 13).


Weiss acknowledges that very many genes have some influence on cognitive ability, but in most cases the influence is secondary or tertiary. He argues that selection for intelligence, particularly in recent times, has operated mostly on a subset of genes with substantial effects. He cites a study by Davis et al. (2015) on the DUF1220 gene, which varies in the number of copies of a protein-coding sequence called CON2. Populations of European descent have 26 to 33 copies, and each additional copy is associated with a 3.3 point increase in IQ. Are there other genes with substantial effects on cognition? Perhaps.



IQ research in the DDR


Weiss grew up in East Germany and did his initial research on IQ there. He witnessed how the genetics of IQ, initially a taboo subject, became more and more acceptable in the socialist regimes of Eastern Europe. The authorities had made a systematic effort to erase class differences and equalize the social environment, only to find that differences in intellectual ability remained.  Indeed, by equalizing the environment, they had made the influence of genes more noticeable:


Contrary to the expectations of the Marxists, equal opportunities under favourable environmental conditions always lead to an increased genotype-phenotype correlation and thus to an increase in 'heredity'. ... This means that the better equal opportunities are guaranteed in an efficient educational system, the greater the variability of people based on genetic differences." (Mohr 1975, p. 48 [transl. by Weiss])


In the 1960s, and even more so in the 1970s, East Germany gave up its policy of preferentially admitting the children of workers or peasants to university … and thus preferentially hiring them for intellectually demanding jobs (Weiss 2020, pp. 44-45). The educational system now became oriented toward performance, with special classes for the highly gifted. Pragmatism was the keynote: the authorities wished to identify talented individuals and help them succeed. Academic research followed the same trend. In 1972, Weiss defended a doctoral dissertation in East Berlin on the inheritance of mathematical and technical abilities (Weiss 2020, p. 47).


On the eve of its dissolution, the Eastern bloc was learning lessons that the Western bloc had not yet learned … or had learned too long ago.





Davis, J. M., Searles, V. B., Anderson, N., Keeney, J., Raznahan, A., Horwood, J., Fergusson, D. M., Kennedy, M. A., Gledd, J. and J. M. Sikela. (2015). DUF1220 copy number is linearly associated with increased cognitive function as measured by total IQ and mathematical aptitude scores. Human Genetics 134: 67-75.


Mohr, H. (1975). Der prinzipielle Konflikt zwischen Biologie und Marxismus. In G. Szczesny (ed.). Marxismus, ernstgenommen: ein Universalsystem auf dem Prüfstand des Wissens. Reinbek bei Hamburg: Rowohlt pp. 30-50


Plomin, R., S. von Stumm. (2018). The new genetics of intelligence. Nature Reviews Genetics 19: 148-159.


Weiss, V. (2020). The Population Cycle that Drives Human History. Leipzig, Germany



Monday, November 30, 2020

The genetics of susceptibility to COVID-19

Left: Frequency of an rs2258666 allele in Indian populations (TT-plus strand or AA-minus strand). Right: COVID-19 case-fatality rate (August 2020).



ACE2 is a cell receptor that mediates the infection of lung tissue by coronaviruses, either the one that causes COVID-19 or others that cause the common cold. The ACE2 gene has 1,700 alleles, some of which are associated with increased susceptibility to coronavirus infection (Frost 2020).


This difference in susceptibility has been shown in a recent Indian study (Srivastava et al. 2020). COVID-19 is most fatal in the western states of Gujarat, Maharashtra, Madhya Pradesh, and Punjab. Conversely, it is least fatal in the northeast states of Assam, Arunachal Pradesh, and Nagaland. This pattern closely correlates with genetic variation at the rs2285666 locus of ACE2. The presence or absence of a single allele explains 35% of the variation in the COVID-19 case-fatality rate.


The authors conclude that some kind of selection has been acting on rs2285666. If we look at the map, susceptibility to COVID-19 seems to be strongest in those regions with the longest history of sedentary living and large urban centers. Conversely, it seems to be weakest in the Northeast, which is home to people who, until recent times, belonged to small communities that routinely moved from one cultivable area to another.


These findings are consistent with the hypothesis that the ACE2 receptor has coevolved with human environments. Because respiratory viruses boost the immune response of lung tissue and thereby prevent more serious pulmonary diseases (e.g., tuberculosis, pneumonia, pneumonic plague), some human populations may have gained protection from severe respiratory infections by becoming more susceptible to mild respiratory infections, such as those normally caused by coronaviruses. This commensal relationship would have been especially adaptive where respiratory pathogens could easily propagate, that is, in crowded environments where many people live in proximity not only to each other but also to livestock. In regions that have long had crowded environments, natural selection may have favored susceptibility to infection by coronaviruses, which are normally mild in their effects, as a means to maintain a strong immune response to deadly pulmonary diseases (Frost 2020).





I'm sorry for the break in my posting. When the pandemic first struck, I expected to have a lot of time on my hands, so I began a series of writing projects: four articles and a manuscript for a book. Unfortunately, my free time dried up over the summer, and my workload became overwhelming. I hope I've now found the right balance between my writing projects and my regular work.




Frost, P. (2020). Does a commensal relationship exist between coronaviruses and some human populations? Journal of Molecular Genetics 3(2): 1-2.


Srivastava, A., A. Bandopadhyay, D. Das, R.K. Pandey, V. Singh, N. Khanam, N. Srivastava, P.P. Singh, P.K. Dubey, A. Pathak, P. Gupta, N. Rai, G.N.N. Sultana, and G. Chaubey. (2020). Genetic Association of ACE2 rs2285666 Polymorphism with COVID-19 Spatial Distribution in India. Frontiers in Genetics. September 25

Wednesday, August 12, 2020

The large society problem in Northwest Europe and East Asia


Allegory of Justice punishing Injustice – Jean-Marc Nattier (Wikicommons). Initially, economic and social activity was organized among closely related individuals, a limitation that kept societies from realizing their full potential as they grew larger. Northwest Europeans and East Asians overcame this limitation through behavioral and mental changes.

I have published an article on "the large society problem in Northwest Europe and East Asia." Comments are welcome.




Kinship was the organizing principle of early societies, defining how people should behave toward each other. Social and economic activity was thus organized mostly among closely related individuals, a limitation that would keep societies from realizing their full potential as they grew larger. The "large society problem" has not been fully solved anywhere, but Northwest Europeans and East Asians have gone the farthest toward a solution. In general, the solution has been to weaken the relative importance of kinship and strengthen forms of sociality that can include everyone, and not just close kin. In particular, one must think and feel in certain ways, i.e., be susceptible to social norms that are absolute, universal, and independent of kinship; feel guilty after breaking social norms; feel empathy for non-kin; and orient oneself toward society. This mindset shows similarities and differences between Northwest Europeans and East Asians. Both groups adapted to a larger social environment by becoming more empathetic toward non-kin and more susceptible to universal social norms. Northwest Europeans became more individualistic while acquiring stronger internal controls of behavior (affective empathy, guilt proneness). East Asians became more collectivistic while acquiring stronger internal controls (cognitive empathy) and stronger external controls (shaming, family-community surveillance, inculcation of normative behavior).





Frost, P. (2020). The large society problem in Northwest Europe and East Asia. Advances in Anthropology 10(3): 214-134.

Monday, August 3, 2020

Declining intelligence in the 20th century: the case of Estonia

Soviet-era stamp. In Estonia, cranial volume shrank between the cohort of girls born in 1937 and those born in 1962, apparently because the intellectually gifted were more likely to pursue higher education and postpone childbearing.


Is the genetic basis for intelligence declining from one generation to the next? That’s the conclusion of several recent studies on alleles associated with high educational attainment. By adding up such alleles over the genome, we can get a person's "polygenic score." By calculating the mean polygenic score for each generation, we can then find out whether this genetic basis is declining.

The polygenic score has declined among Icelanders since the cohort born in 1910 and among Euro Americans between the 1931 and 1953 cohorts (Beauchamp 2016; Kong et al. 2017). The Icelandic study is especially interesting because that country took in very few immigrants during the period under study. The decline was thus driven by internal factors. One reason seems to be the tendency of university-educated people to delay reproduction and have fewer children. But that's not the whole story. Even among Icelanders who didn’t pursue higher education, fertility was lower among the intellectually gifted, apparently because their intelligence was associated with a desire to plan for the future and delay gratification.

Before the twentieth century, such forward-looking people were reproductively successful. They were the ones who had enough resources to survive disasters of one sort or another: famine, disease, the Little Ice Age, etc. Today, such disasters are a lot less deadly, and it no longer matters so much whether one is a grasshopper or an ant.

Moreover, because of demographic and cultural changes during the twentieth century, it’s no longer possible to count on the same degree of assistance for child-raising from relatives and grandparents. With childbearing at later ages, grandparents are either dead or too frail to help. With people moving around more, not all relatives live nearby. If you’re the sort of person who plans for the future and delays gratification, you may be a lot more intimidated than your forbears by the costs of raising a family.

Shrinking cranial volume in Estonians

Cranial volume correlates with IQ and with educational attainment, albeit imperfectly (see Frost 2020). Has it been declining in tandem with the decline in alleles for educational attainment?

In Soviet-era Estonia, cranial volume was one of several anthropometric traits that were measured in girls born between 1937 and 1962. Because the measurements were mandatory, there was no volunteer basis; mortality bias was minimal because all the participants were younger than 20. In this respect, the study is better than Western biobank studies. On the other hand, the results may be less applicable to Western populations, given the differences in demographic history. Estonia had no postwar baby boom. Fertility then rose from the late 1960s until the breakup of the Soviet Union. By the late 1980s, fertility was actually higher in Estonia than in any other major region of Europe.

Nonetheless, there were demographic similarities between Soviet Estonia and the West, particularly the rising prevalence of single mothers and the influence of education on fertility:

- Divorce rates began to rise during the interwar years, equalling or exceeding those of Scandinavia from the 1970s onward.

- Throughout the twentieth century, Estonian women with only primary education bore 0.5 to 0.75 more children on average than women with tertiary education. In the population under study, taller children and those with larger crania were more likely to go on to secondary and/or tertiary education, independently of sex, socioeconomic position, and rural vs urban origin (Valge et al. 2019).

The second factor seems to explain why cranial volume declined from the older cohorts to the younger ones:

[...] the majority of selection for smaller cranial volume acted indirectly via educational attainment, whereas the direct path of selection in the SEM model was non-significant (Figs. 2 and 4). In other words, consistent with our prior expectations, girls with larger heads were selected against because they were more likely to obtain higher education than girls with smaller heads. Lower education (Tiit, 2013) and rural origin (Kulu, 2005) have been independently and additively associated with higher fertility in Estonia throughout the past century. The reason for the link between education and fertility is that early reproduction, a major determinant of LRS, is not compatible with schooling for both cultural and genetic reasons. (Valge 2020)

 It is doubtful that this decline is due to ethnic change. All of the girls were from Estonian schools (Russian-speakers had their own schools). Nonetheless some of them were of mixed background. According to a personal communication from the corresponding author, 84% of the fathers and 93% of the mothers were Estonian. Ideally, the study should be redone without individuals of mixed parentage. The problem here is not only that one of the parents was non-Estonian but also that such individuals were disproportionately economic migrants who had trouble finding suitable work elsewhere in the Soviet Union.

Other anthropomorphic changes

Height also declined. Unlike cranial volume, this decline was not wholly explained by educational/socioeconomic differences:

Notably, higher reproductive success of shorter girls in Estonia could not be entirely ascribed to indirect selection via educational attainment, nor via other measured socioeconomic variables such as rural/urban origin, although indirect selection via education did account for a large portion of total selection (Fig. 4). The finding that selection against height remains after controlling for education or income (that favours less-educated individuals who are generally shorter than highly-educated ones) is consistent with findings of studies reviewed by Stulp and Barrett (2016).

Female hips and female jaws became narrower even after controlling for educational/socioeconomic differences. There seems to have been selection for rounder female faces, but this selection is significant only if one allows for nonlinear effects. Finally, there was no direct selection on two markers of overall health and nutritional status: handgrip strength and lung capacity.

In general, "direct selection favoured shorter, slimmer and lighter girls with smaller heads, more masculine facial and body shapes and slower rates of sexual maturation."


The genetic basis for intelligence has declined in European populations, apparently since the early twentieth century. This decline is attested by two "hard" measures: 1) alleles associated with educational attainment; and 2) cranial volume. Furthermore, it is attested in two relatively homogenous societies, i.e., Iceland and Estonia.

In Estonia, the decline seems entirely due to the intellectually gifted going to university and postponing family formation. In Iceland, this factor explains only part of the decline: the intellectually gifted chose to postpone family formation even when they didn't go to university. Perhaps the Soviet system was better at steering gifted individuals into higher education.

On a final note, this problem will not go away on its own. If we wish to have large numbers of intellectually gifted people who plan for the future and delay gratification, we will need to reverse certain social and cultural changes of the twentieth century.

Comments by Peeter Horak

In an email, Peeter pointed out that the decrease in height due to natural selection might be offset by an increase in height due to lower pathogen load (as a result of vaccination and antibiotics, see Hõrak and Valge 2015). In addition, we currently don't know the direction of selection on boys. It may entirely cancel out natural selection on girls if men's income and education correlate positively with their reproductive success. In the sample under study, taller boys and those with larger heads went on to obtain more education; if they were reproductively successful, there would be sexually antagonistic selection: selection would favor larger boys and smaller girls at the same time.


Beauchamp, J.P. (2016). Genetic evidence for natural selection in humans in the contemporary United States. Proceedings of the National Academy of Sciences 113(28): 7774-7779

Frost, P. (2020). Did women jumpstart recent cognitive evolution? Evo and Proud, July 1

Hõrak, P., and M. Valge. (2015). Why did children grow so well at hard times? The ultimate importance of pathogen control during puberty, Evolution, Medicine, and Public Health, 2015 (1): 167–178,

Kong, A., M.L. Frigge, G. Thorleifsson, H. Stefansson, A.I. Young, F. Zink, G.A. Jonsdottir, A. Okbay, P. Sulem, G. Masson, D.F. Gudbjartsson, A. Helgason, G. Bjornsdottir, U. Thorsteinsdottir, and K. Stefansson. (2017). Selection against variants in the genome associated with educational attainment. Proceedings of the National Academy of Sciences 114(5): E727-E732

Valge, M., P. Horak, and J.M. Henshaw. (2020). Natural selection on anthropometric traits of Estonian girls. Evolution and Human Behavior in press.

Valge, M, R. Meitern, and P. Horak. (2019). Morphometric traits predict educational attainment independently of socioeconomic background. BMC Public Health 19: 1696.

Saturday, July 25, 2020

Selection for slow life history?

One of several posters to promote family formation in the dwindling Parsi community (Jiyo Parsi)

In India, and overseas, the Parsis are renowned for their achievements, particularly in business but also in science, culture, and philanthropy. 

They are also known for something else: they’re dying out. From 114,000 in 1941, they were down to half that number by 2011. Today, more than 30% of Parsis don't marry, and an equal proportion are over 60 years old. Their fertility rate is 0.8—in other words, the average Parsi woman gives birth to less than one child during her lifetime. This existential crisis is worrying not only the Parsis but also the Indian government. In 2013, a program was set up to subsidize fertility treatments and promote family formation in the community (Dore 2017).

Extinction is irreversible. If the Parsis die out, the loss will be greatest in those things we don’t fully understand: the workings of the human mind. That is precisely where the Parsis have succeeded the most. How much of that success has been due to learning and how much to innate factors?

A few steps toward an answer were taken by Greg Cochran and Henry Harpending in their paper on Ashkenazi intelligence:

Since strong selection for IQ seems to be unusual in humans (few populations have had most members performing high-complexity jobs) and since near-total reproductive isolation is also unusual, the Ashkenazim may be the only extant human population with polymorphic frequencies of IQ-boosting disease mutations, although another place to look for a similar phenomenon is in India. In particular, the Parsi are an endogamous group with high levels of economic achievement, a history of long-distance trading, business and management, and who suffer high prevalences of Parkinson disease, breast cancer and tremor disorders, diseases not present in their neighbours. (Cochran et al. 2006)

Such disorders may be a side-effect of strong selection for intelligence over a short time in a small population. This was historically the case with Ashkenazi Jews. They are unusually prone to four neurological disorders: Tay-Sachs, Gaucher, Niemann-Pick, and mucolipidosis type IV. All four affect the brain by increasing the capacity of lysosomes to store sphingolipid compounds for axonal growth and branching. Furthermore, Tay-Sachs is caused in Ashkenazi Jews by two unrelated mutations and Gaucher disease by five. Random chance simply cannot explain why so many mutations exist in the same metabolic pathway and have reached such high frequencies.

Those mutations apparently spread through heterozygote advantage. Though harmful when two copies are inherited from both parents, they are beneficial when only one copy is inherited, as is more often the case. With a better supply of sphingolipids and no adverse effects, the brain can process information more efficiently.

Jared Diamond (1994) was the first to argue that chance cannot explain the high prevalence of so many lysosome storage disorders in a single population. He suggested the cause was selection for intelligence. His theory was then developed by Cochran et al. (2006). Other researchers have further confirmed Diamond’s theory by showing that Ashkenazim have high frequencies of alleles associated with educational attainment (Dunkel et al. 2019; Piffer 2019).

Frequent neurological/cerebral diseases among the Parsis

We see a similarly high prevalence of neurological or cerebral diseases among the Parsis. Parkinson’s disease is considerably more prevalent among them than among other Indians or even people of developed countries. Strokes are at least twice as common. Essential tremors are exceptionally frequent (Gourie-Devi 2014).

These diseases seem to have a genetic basis among the Parsis. A mitochondrial genome study found 420 unique genetic variants within that community, 178 of which are associated with Parkinson's disease. Others are linked to other neurodegenerative disorders, as well as colon, breast, and prostate cancer. A surprising number of these unique variants, 217, are linked to increased longevity. Finally, and perhaps curiously, some variants are linked to asthenozoospermia, i.e., reduced sperm motility (Patell 2020)

The above results are consistent with the findings of an earlier genetic study of the Parsis, specifically their autosomal, Y chromosome, and mitochondrial DNA. Signals of selection were strongest in SNPs associated with humoral immunity, cerebellar physiology, and neurological disorders like early epilepsy (Lopez et al. 2017).


The evidence is only suggestive, but it looks like the Parsis have undergone strong selection for intelligence over a relatively short time; hence, the high prevalence of neurological disorders.

In addition, this community seems to have adapted to its economic and social niche through a "slow life history" strategy. The Parsis are predisposed to live longer and thus learn more over a longer time. They may also be predisposed to longer birth intervals and higher parental investment in each child (K selection). Such a reproductive strategy is consistent with lower male fertility.

A slower life history, combined with higher intelligence, may have assisted the trading lifestyle of the Parsi community. Trade requires a high level of cognitive ability, particularly for literacy and numeracy, as well as lower time preference and a longer learning period. 

Ironically, low time preference may explain the demographic decline of the Parsis, and other people like them. If you’re future-oriented, you’re also keenly aware of future costs, particularly those of getting married and having a family. So you’ll postpone marriage and family formation until you’re financially ready. Unfortunately, that day may never come. Or it may come too late.

This problem was known to traditional societies, and there used to be social incentives to ensure that young people would marry before they got too old. Unfortunately, those incentives have disappeared in modern societies.

If you wait to check all the boxes, you may check into an old-age home … alone.


Cochran, G., J. Hardy, and H. Harpending. (2006). Natural history of Ashkenazi intelligence. Journal of Biosocial Science 38: 659-693

Diamond, J.M. (1994). Jewish Lysosomes. Nature 368: 291-292.

Dore, B. (2017). Glimmer of hope at last for India's vanishing Parsis. BBC News

Dunkel, C.S., Woodley of Menie, M.A., Pallesen, J., and Kirkegaard, E.O.W. (2019). Polygenic scores mediate the Jewish phenotypic advantage in educational attainment and cognitive ability compared with Catholics and Lutherans. Evolutionary Behavioral Sciences 13(4): 366-375.

Gourie-Devi M. (2014). Epidemiology of neurological disorders in India: review of background, prevalence and incidence of epilepsy, stroke, Parkinson's disease and tremors. Neurology India 62(6): 588-598.  

López, S., Thomas, M. G., van Dorp, L., Ansari-Pour, N., Stewart, S., Jones, A. L., Jelinek, E., Chikhi, L., Parfitt, T., Bradman, N., Weale, M. E., and Hellenthal, G. (2017). The genetic legacy of Zoroastrianism in Iran and India: insights into population structure, gene flow, and selection. American Journal of Human Genetics 101(3): 353-368.

Patell, V.M., N. Pasha, K. Krishnasamy, B. Mittal, C. Gopalakrishnan, R. Mugasimangalam, N. Sharma, A-K. Gupta, P. Bhote-Patell, S. Rao, R. Jain, and The Avestagenome Project. (2020). The First complete Zoroastrian-Parsi Mitochondria Reference Genome: Implications of 2 mitochondrial signatures in an endogamous, non-smoking population. bioRxiv preprint doi:

Piffer, D. (2019). Evidence for Recent Polygenic Selection on Educational Attainment and Intelligence Inferred from Gwas Hits: A Replication of Previous Findings Using Recent Data. Psych 1(1): 55-75.