Monday, May 16, 2022

When did Europe pull ahead?


Medieval market – Nicole Oresme (15th century) (Wikicommons)


In terms of GDP per capita growth, northwest Europe began to surpass the rest of the world during the 14th century: before the conquest of the Americas, the invention of printing, the Atlantic slave trade, and the Protestant Reformation.



In a recent post, Steve Sailer asks why the European world pulled ahead of the non-European world between 1000 and 1500 AD:


[…] much of the non-European world entered a sort of cultural recession well before Europeans directly interfered with them. If you look at, say, Charles Murray’s 2003 book Human Achievement, several major non-European civilizations appear to have lost momentum in making progress in the arts and sciences over roughly the time period of 1000 or maybe 1250 to 1500. (Sailer 2022)


For Steve, the reason was the collapse of the Mongol Empire during the 14th century. That century was indeed a turning point for Europe, particularly for England and Holland:


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)


This process began before the European conquest of the Americas, the invention of printing, the creation of modern finance institutions, the Atlantic slave trade, or the Protestant Reformation. None of these can be proper explanations for this "little divergence." (Greer 2013a; see also Thompson 2012 and Hbd *chick 2013).


The divergence began within a part of Europe that was much less affected by the rise and fall of the Mongol Empire. Moreover, if we compare southern Europe with North Africa during the same period, we see the same divergence that we see more generally between Christian Europe and the rest of the world. Yet North Africa was never conquered by the Mongols.


It looks like internal causes were responsible for the divergence between Christian Europe and the rest of the world. Those causes seem to have their point of origin in northwest Europe during the long period from 500 to 1500 AD. In that region, the Western Church consolidated a pre-existing pattern of small, nuclear households, weak family ties, and residential mobility, thus strengthening a mindset of individualism and impersonal sociality (Frost 2020; Schulz et al. 2019). Then, from 1000 AD onward, the Western Church strove to pacify social relations (Frost and Harpending 2015). Those two factors—an individualistic mindset operating in a pacified social environment—allowed the market economy to expand into all areas of life and eventually replace kinship as the main organizing principle of society (Frost 2020; Macfarlane 1978; Weber 1930).


The expansion of the market economy went hand in hand with the expansion of the middle class. In England, this class began to expand in the twelfth century and would gradually replace the lower classes through downward mobility. By the 1800s, its lineages accounted for most of the English population. English society thus became more middle class in its values: "Thrift, prudence, negotiation, and hard work were becoming values for communities that previously had been spendthrift, impulsive, violent, and leisure loving" (Clark 2007, p. 166). The same process took place elsewhere in Western Europe and more generally throughout Europe to varying degrees and over different timescales (Frost 2019, p. 176).


In sum, between 500 and 1500 AD the Western Church created a system of social reproduction that would have far-reaching demographic, behavioral, and economic consequences. To understand that system, one must understand not only the Bible but also the writings of early and medieval Christianity, as well as the pagan Germanic elements it incorporated (Russell 1994). Finally, one must understand the preceding system, and its failings.


The pre-Christian world: demographic and cognitive decline


Ancient DNA from Greece suggests that mean cognitive ability began to decline at some point during Classical Antiquity (Woodley of Menie et al. 2019). A similar decline probably happened throughout the Mediterranean basin and the Middle East of that time.

There were three main causes:


·         A decline in fertility and family formation, particularly among the upper classes (Caldwell 2004; Hopkins 1965; Roetzel 2000, p. 234);

·         A corresponding increase in female hypergamy, often by freed slaves, which reduced the reproductive importance of upper-class women (Perry 2013);

·         An increase in the slave population, particularly foreign slaves (Harris 1999). This ongoing influx disrupted the process of local cognitive evolution. Even if there had been demographic overflow from the upper classes, that overflow could not have replaced the lower classes, since those classes were being replaced from external sources.


Christianity and Islam both tried to correct the ruinous demographic state of the ancient world. Islam succeeded in reversing negative population growth but failed to restart cognitive evolution. In some ways, it made such evolution more difficult. Islam increased female hypergamy by permitting male polygamy, thus further reducing the reproductive importance of upper-class women (van den Berghe 1960). Foreign slaves were also imported on a larger-scale than in antiquity, thus further disrupting local cognitive evolution (Lewis 1990). Finally, the upper classes tended to congregate in urban areas, where the death rate was higher.


Before the 20th century, population growth had been sluggish in the Muslim world. Wherever Muslims coexisted with Christians, the latter community was often the one that grew at a faster pace. This was the case in the Balkans:


By the end of the eighteenth century the Muslim population had entered a period of comparative economic and moral decline. Several explanations have been offered for this development. Certainly the fact that the Muslim population provided the soldiers contributed to its ultimate weakening. Their concentration in towns also made them more susceptible to the ravages of plague and other diseases. Turkish customs, particularly the practice of polygamy, played a part. This process of decay was clearly illustrated in the eighteenth century in the changing demography of the Balkan towns where Christian and national elements formed an increasingly larger proportion of the population (Jelavich and Jelavich, 1977, pp. 6-7)


Christianity, especially Western Christianity, succeeded not only in promoting population growth but also in restarting cognitive evolution, specifically by supporting the formation of monogamous families, by discouraging slavery, at least during the long period from 500 to 1500 AD, and eventually by creating the peace, order, and stability that allowed the middle class to expand and become dominant. The rise of Christian Europe actually began before its expansion into the Americas and Asia. The latter was, in fact, a consequence of the former.




Caldwell, J.C. (2004). Fertility control in the classical world: Was there an ancient fertility transition?  Journal of Population Research 21:1.  


Clark, G. (2007). A Farewell to Alms. A Brief Economic History of the World. Princeton University Press: Princeton.


Frost, P. (2019). The Original Industrial Revolution. Did Cold Winters Select for Cognitive Ability? Psych 1(1): 166-181.


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


Frost, P. and H. Harpending. (2015). Western Europe, state formation, and genetic pacification. Evolutionary Psychology 13(1): 230-243.


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.    


Harris, W. (1999). Demography, Geography and the Sources of Roman Slaves. Journal of Roman Studies 89, 62-75.  


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


Hopkins, K. (1965). Contraception in the Roman Empire. Comparative Studies in Society and History 8(1): 124-151.  


Jelavich, C. and B. Jelavich. (1977). The Establishment of the Balkan National States, 1804-1920. Seattle: University of Washington Press.


Lewis, B. (1990). Race and Slavery in the Middle East. New York: Oxford University Press.


Macfarlane, A. (1978). The Origins of English Individualism: The Family, Property and Social Transition. Oxford: Blackwell.


Perry, M.J. (2013). Gender, Manumission, and the Roman Freedwoman. Cambridge University Press.


Roetzel, C.J. (2000). Sex and the single god: celibacy as social deviancy in the Roman period. In: S.G. Wilson and M. Desjardins (eds). Text and Artefact in the Religions of Mediterranean Antiquity. Essays in Honour of Peter Richardson. Wilfrid Laurier University Press (pp. 231-248).


Russell, J.C. (1994). The Germanization of Early Medieval Christianity: A Sociohistorical Approach to Religious Transformation. New York; Oxford: Oxford University Press.


Sailer, S. (2022). Why was much of the non-European world stagnating well before 1492? The Unz Review, May 10  


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.  


Thompson, D. (2012). The Economic History of the Last 2000 Years: Part II, The Atlantic, June 20,  


Van den Berghe, P.L. (1960). Hypergamy, Hypergenation, and Miscegenation. Human Relations 13(1):83-91.   


Weber, M. (1930). The Protestant Ethic and the Spirit of Capitalism. New York: Charles Scribner’s Sons.


Woodley of Menie, M.A., J. Delhez, M. Peñaherrera-Aguirre, and E.O.W. Kirkegaard. (2019). Cognitive archeogenetics of ancient and modern Greeks. London Conference on Intelligence  

Monday, May 9, 2022

Red is beautiful: Perceived femininity of skin color in an African population


Perceived masculinity and femininity of facial skin color. Cameroonian women rated faces of Cameroonian men, and Cameroonian men rated faces of Cameroonian women (Fiala et al. 2022, Supplementary Material).




Women are the fair sex. They are paler than men, who conversely are ruddier and browner. Today, that sexual dimorphism is hardly noticed in Western societies, having been overwhelmed by much larger differences of race and ethnicity and further obscured since the 1920s by the tanning fad (Segrave 2005). But it was noticed earlier. Wherever the visual arts developed—ancient Egypt, the Greco-Roman world, early South and East Asia, Mesoamerica—female figures were given a lighter hue and male figures a darker one (Capart 1905, pp. 26-27; Eaverly 2013; Frost 2010, pp. 35-81; Pallottino 1952, pp. 34, 45, 73, 76-77, 87, 93, 95, 105, 107, 115; Soustelle 1970, p. 130; Tegner 1992; Wagatsuma 1967).


Sexual dimorphism in skin pigmentation


Skin color was first measured objectively in the 1930s, when spectrophotometers became commercially available. By measuring how much light the skin reflects across the visible spectrum, and how much it absorbs, one could identify its pigments and quantify their relative importance. Edwards and Duntley (1939) concluded that male and female complexions differ because of differing concentrations of melanin (brown), hemoglobin (red), and carotene (yellow).


Castration keeps men from acquiring their distinctive complexion:


One of the outstanding characteristics of a human male castrate is the paleness of the skin. After treatment with androgenic hormone, however, the individual takes on a darker and more ruddy hue. This observation suggests that the skin of the castrate is deficient in melanin and blood, and that the androgenic hormone increases the content of these substances in the integument. (Edwards et al. 1941)


Estrogen has similar but much weaker effects, which are further reduced by the other female hormone, progesterone. Ovariectomy thus has much less impact on female skin than castration has on male skin (Edwards and Duntley 1949). The sex hormones seem to alter skin pigmentation not only through ongoing transient effects but also through permanent organizational effects before birth and at puberty.


A hormonal causation is also suggested by the digit ratio. This is the length of the index finger divided by the length of the ring finger, and it tells us the relative proportions of estrogens to androgens in body tissues during development. In adults, the digit ratio correlates with lightness of female skin but not with lightness of male skin (Manning et al. 2004).


Sexual dimorphism in tanning capacity


Men and women likewise differ in tanning capacity. Men tan more than women even when both are equally exposed to the sun. This was shown in a New Guinea study of three body sites: skin on the unexposed upper inner arm; skin on the exposed forearm; and time spent in the sun. Despite identical sun exposure, the men were darker than the women, and more so on exposed skin (Harvey 1985). The same finding appears in another New Guinea study, whose author ruled out the possibility of the women being less exposed, "as in most parts of New Guinea the adult females are responsible for most of the food cultivation and are therefore exposed almost continuously to sunlight." (Walsh 1964).


Differences between human populations


Skin color is more sexually dimorphic where people are medium-colored and less so where they are very fair or very dark (Frost 2007; Madrigal and Kelly 2007). This sexual dimorphism cannot fully express itself in a very fair population because female skin encounters a physiological limit when it lightens after puberty. In a very dark population, male skin likewise encounters a physiological limit to further darkening.


Are there other population differences? Has this sexual dimorphism evolved differently in different populations?


Apparently. A recent paper shows that this sex difference differs qualitatively between Europeans and sub-Saharan Africans. When Fiala et al. (2022) measured the skin color of individuals from the Czech Republic and Cameroon, they found that women had fairer skin in both groups. But their skin was fairer in different ways. Among the Czechs, female skin was less red than male skin, in line with previous studies on European or Euro-American subjects. Among the Cameroonians, however, female skin was redder than male skin, and also more yellow.


Adaptation to the natural environment?


Is the redder complexion of African women an adaptation to the natural environment? If the skin is better supplied with blood, does it better cope with UV radiation, heat load, skin injuries, or some other aspect of a tropical environment? Let’s examine these three factors, while keeping in mind that they would have to be more fitness-reducing for African women than for African men.


UV radiation. The yellow pigment of skin (carotene) does provide some protection from UV (Stahl et al. 2012). So it’s plausible that African women compensate for having less melanin in their skin by having more carotene. On the other hand, there is no evidence that the red pigment of skin (hemoglobin) provides UV protection.


Heat load. When more blood is flowing to the skin, heat is radiated away more easily from the body (Hertzman 1959). It may be, then, that the increased redness of African female skin serves to disperse body heat in warmer climates. Nonetheless, we still have to explain why heat load is more fitness-reducing for African women than for African men.


Skin injuries. When more blood is flowing to the skin, wounds heals faster because more leukocytes can reach skin tissues and fight potential infections (Mathieu et al. 2006). Again, we still have to explain why this factor would matter more for African women than for African men. Coetzee et al. (2012) raise a similar objection: if ruddiness is attractive because it indicates physical health, why is it considered unattractive in the case of European women or African men?


Adaptation to the social environment?


Alternatively, the redder complexion of African women may have evolved as an adaptation to the social environment, specifically for gender recognition. In a study using Euro-American participants, people could tell whether a facial photo was male or female, at a rate much higher than chance, even when the image was blurred and provided no useful information other than the degree of redness (Tarr et al. 2001). Sexual dimorphism in skin color has two components: hue (degree of brownness and redness) and luminosity (degree of contrast between lightness of facial skin and darkness of lip/eye area). Hue is the fast channel for gender recognition. If the face is too far away or the lighting too dim, the mind will switch to the slower but more accurate channel of luminosity (Dupuis-Roy et al. 2009; Dupuis-Roy et al. 2019; Jones et al. 2015; Nestor and Tarr 2008a; Nestor and Tarr 2008b; Tarr et al. 2001; Tarr, Rossion, and Doerschner 2002). This gender cue may serve not only to tell men and women apart but also to modify male behavior by reducing aggressiveness and stimulating feelings of care and protection (Frost 2011).


African women maintain this gender cue through a different mix of skin pigments. They have more carotene in their skin, and thus a yellower complexion, to offset the loss of UV protection due to having less melanin. Unlike European women, they also have more blood in their skin and thus a redder complexion. Why is this? Perhaps increased redness does not visually alter dark skin in the same way that it visually alters light skin. When redness is increased, the dark skin of African women may look lighter and the light skin of European women may look darker. The social environment has thus favored lighter female skin in both populations, but the mix of pigments is different.


This gender cue was studied by Fiala et al. (2022) in their Czech/Cameroonian study. Cameroonian women were asked to rate facial photos of Cameroonian men, and Cameroonian men were asked to rate facial photos of Cameroonian women. The results showed a significant correlation between skin color and perceived masculinity/femininity:


The slope between perceived masculinity and colour (higher scores along all three CIELab dimensions, meaning basically lighter skin that allows both redness and yellowness to stand out) of Cameroonian men was negative - 0.29 (CI: - 0.52, - 0.05). In Cameroonian women, the slope between perceived femininity and colour was conclusively positive 0.52 (CI: 0.27, 0.76).


[…] More masculine men in the Cameroonian sample have therefore darker, less red, and less yellow skin colour.

[…] More feminine women thus have a lighter, yellower, and redder skin than less feminine women.


There was no such correlation among the Czechs. This second finding seems to contradict previous findings that facial skin color is used for gender recognition (see above). In those studies, however, the participants were Euro-American or Euro-Canadian, and they were not necessarily conscious of the visual cues they were using. At least on a conscious level, the sex difference in skin color has lost its social significance within the Western world, largely because of the growing importance of racial/ethnic differences in real life and in the virtual life of advertising and the mass media. In addition, the naturally lighter complexion of women has often been reduced or eliminated through deliberate tanning.


Ethnographic data


When we were preparing our joint paper on skin color preference, Pierre van den Berghe examined the Human Relations Area Files, a cross-cultural database. He found a strong association in traditional societies between femininity and lightness of skin color: the ideal woman was described as “white” in Europe, the Middle East, and East Asia, as “golden” in Southeast Asia, and as “red” in sub-Saharan Africa (van den Berghe and Frost 1986). We were somewhat surprised to see this idealization of female redness in different ethnographic accounts:


Tallensi (Ghana) ‑

“In skin colour they vary from black through chocolate brown to bronze, which the natives call “red” (bon‑ze'e) and regard as the most attractive bodily hue.” (Fortes 1945, p. 7)


Hausa (Nigeria) ‑

“Light skin colour, referred to as “red”, ranks high in the Hausa criteria of beauty; many variations of colour, from black to a very light reddish brown are seen.” (Smith 1965, p. 264)


Igbo (Nigeria) ‑

“In Ibo culture, however, these yellowish or reddish complexions are considered more beautiful than the darker, ‘blacker,’ complexions.” (Ardener 1954, pp. 71-72)


Somali (Somalia) ‑

“Men appreciate women of good height and stature, with good hips and breasts, and plump but not fat.  A reddish tinged skin is thought highly of in preference to a dark dull black.” (Lewis 1962, p. 13)


This ideal is explained at some length by Lugira (1970, pp. 34-35) with respect to the Ganda people of Uganda:


The Ganda concept of skin pigmentation considers light coloured complexions to be differing shades of white.  A dark brown skin colour is said to be — eruyeru, that is, somewhat white.  A really brown‑reddish‑yellow person is said to be mweru = white, which in comparison would be considered to be blonde; and this in the Ganda aesthetic language is considered as red = myufu, the most perfect skin pigmentation. (Lugira 1970, pp. 34‑35)


So the question remains open. Female skin may be redder in Africa because of selection by the natural environment, perhaps as a means to reduce heat load or facilitate wound healing. There is also evidence, however, for selection by the social environment.




Ardener, E.W. (1954). Some Ibo attitudes to skin pigmentation. Man 54: 71-73.


Capart, J. (1905). Primitive Art in Egypt. London: H. Grevel.


Coetzee, V., S.J. Faerber, J.M. Greeff, C.E. Lefevre, D.E. Re, and D.I. Perrett. (2012). African Perceptions of Female Attractiveness. PLoS ONE 7(10): e48116.


Dupuis-Roy, N., S. Faghel-Soubeyrand, and F. Gosselin. (2019). Time course of the use of chromatic and achromatic facial information for sex categorization. Vision Research 157: 36-43.


Dupuis-Roy, N., I. Fortin, D. Fiset, and F. Gosselin. (2009). Uncovering gender discrimination cues in a realistic setting. Journal of Vision 9(2): 10, 1-8.


Eaverly, M.A. (2013). Tan Men/Pale Women. Color and Gender in Archaic Greece and Egypt, a Comparative Approach. Ann Arbor: The University of Michigan Press.


Edwards, E.A., and S.Q. Duntley. (1939).The pigments and color of living human skin. American Journal of Anatomy 65(1): 1-33.


Edwards, E.A., and S.Q. Duntley. (1949). Cutaneous vascular changes in women in reference to the menstrual cycle and ovariectomy. American Journal of Obstetrics & Gynecology 57(3): 501-509.


Edwards, E.A., J.B. Hamilton, S.Q. Duntley, and G. Hubert. (1941). Cutaneous vascular and pigmentary changes in castrate and eunuchoid men. Endocrinology 28(1): 119-128.


Fiala, V., P. Ture?ek, R.M. Akoko, Š. Pokorný, and K. Kleisner. (2022). Africans and Europeans differ in their facial perception of dominance and sex-typicality: a multidimensional Bayesian approach. Scientific Reports 12(1): 6821.


Fortes, M. (1945). The Dynamics of Clanship among the Tallensi. London: Oxford University Press.


Frost, P. (2007). Comment on Human skin-color sexual dimorphism: A test of the sexual selection hypothesis. American Journal of Physical Anthropology 133(1): 779-781.


Frost, P. (2010). Femmes claires, hommes foncés. Les racines oubliées du colorisme. Quebec City: Les Presses de l'Université Laval, 202 p.


Frost, P. (2011). Hue and luminosity of human skin: a visual cue for gender recognition and other mental tasks. Human Ethology Bulletin 26(2): 25-34.


Harvey, R. G. (1985). Ecological factors in skin color variation among Papua New Guineans, American Journal of Physical Anthropology 66(4): 407-416.


Hertzman, A.B. (1959). Vasomotor regulation of cutaneous circulation. Physiological Reviews 39(2):280-306. doi: 10.1152/physrev.1959.39.2.280. PMID: 13645236.


Jones, A.L., R. Russell, and R. Ward. (2015). Cosmetics alter biologically-based factors of beauty: evidence from facial contrast. Evolutionary Psychology 13(1):


Lewis, I.M. (1962). Marriage and the Family in Northern Somaliland. Kampala: East African Institute of Social Research.


Lugira, A.M. (1970). Ganda Art. Kampala: Osasa pub.


Madrigal, L., and W. Kelly. (2006). Human skin-color sexual dimorphism: A test of the sexual selection hypothesis. American Journal of Physical Anthropology 132(3): 470-482.


Manning, J.T., P.E. Bundred, and F.M. Mather. (2004). Second to fourth digit ratio, sexual selection, and skin colour. Evolution and Human Behavior 25(1): 38-50.


Mathieu, D., J.C. Linke, and F. Wattel. (2006). Non-Healing Wounds. Handbook on Hyperbaric Medicine. Springer, pp. 401-428.


Nestor, A., and M.J. Tarr. (2008a).The segmental structure of faces and its use in gender recognition. Journal of Vision, 8(7): 7, 1-12. .


Nestor, A., and M.J. Tarr. (2008b). Gender recognition of human faces using color. Psychological Science 19(12): 1242-1246.


Pallottino, M. (1952). Etruscan Painting. Lausanne: Skira.


Segrave, K. (2005). Suntanning in 20th Century America. Jefferson (North Carolina): McFarland & Company.


Smith, M.F. (1965). Baba of Karo: A Woman of the Muslim Hausa. London: Faber & Faber.


Soustelle, J. (1970). The Daily Life of the Aztecs. Stanford, California: Stanford University Press.


Stahl, W., and H. Sies. (2012). β-Carotene and other carotenoids in protection from sunlight. The American Journal of Clinical Nutrition 96(5): 1179S–1184S


Tarr, M.J., D. Kersten, Y. Cheng, and B. Rossion. (2001). It's Pat! Sexing faces using only red and green. Journal of Vision 1(3): 337, 337a.


Tarr, M. J., B. Rossion, and K. Doerschner. (2002). Men are from Mars, women are from Venus: Behavioral and neural correlates of face sexing using color. Journal of Vision 2(7): 598, 598a,


Tegner, E. (1992). Sex differences in skin pigmentation illustrated in art. The American Journal of Dermatopathology 14(3): 283-287.


van den Berghe, P.L., and P. Frost. (1986). Skin color preference, sexual dimorphism and sexual selection: A case of gene-culture co-evolution? Ethnic and Racial Studies 9(1): 87-113.


Wagatsuma, H. (1967). The social perception of skin color in Japan. Daedalus 96(2): 407-443.


Walsh, R. J. (1964). Variation in the melanin content of the skin of New Guinea natives at different ages. Journal of Investigative Dermatology 42(3): 261-265.


Saturday, April 30, 2022

Recent cognitive evolution in West Africa: the Niger's role


Before European contact, West African societies were more complex in the north and the east, i.e., in the Sahel and the Nigerian forest. This pattern is mirrored geographically by the frequencies of alleles associated with cognitive ability (Piffer 2021, Fig. 7).



Cognitive evolution did not end when Homo sapiens began. It continued at different rates of change and in different ways in different human populations. This is no less true for Sub-Saharan Africa, especially West Africa.


Before European contact, West African societies were more complex in the north and the east, i.e., in the Sahel and the Nigerian forest. Those areas saw the creation of towns, the formation of states, and increasing use of metallurgy and luxury goods from the fourth century onward.


This increase in social complexity used to be attributed to the influence of Arab traders from North Africa and the Middle East, but we now have archaeological evidence of urbanism and long-distance trade as far back as 300 AD—long before the arrival of Arab traders (McIntosh and McIntosh 1988, pp. 114-116). A Niger Delta site, dated to the 9th century, has yielded bronze objects that show little if any Arab influence. The bronze has an unusually high silver content and only traces of zinc, an alloy not used in either Europe or the Arab world at that time (McIntosh and McIntosh 1988, pp. 120-121). While the increase in social complexity was undoubtedly assisted by Arab traders and, later, European traders, it seems to have begun as an indigenous development along the Niger River, which served as West Africa’s main trading route between the coast and the interior:


In the case of the Middle Niger and the Nigerian forest, trade has figured prominently in explanations of increasing complexity. Local or regional trade in kola (at Ife) and stone and iron (at Jenne-jeno) are postulated as the small-scale beginnings of exchange systems that rapidly expanded. […] such goods were but the visible tip of a vast iceberg of archaeologically undetectable trade commodities, such as slaves, food staples, condiments, salt, and oil […]. The natural ecological zonation of the subcontinent would have encouraged exchange of foodstuffs and salt between adjacent zones from very early on. (McIntosh and McIntosh 1988, p. 122)


This trade accelerated with the formation of states and ruling elites. A positive feedback loop developed in which trade was “as much a symptom as a cause of complexity.”  By supplying materials for artistic and ceremonial production, it gave “elites opportunities to appropriate materials and symbols and to manipulate them in ways that legitimize their power” (McIntosh and McIntosh 1988, p. 123). Trade thus stimulated elite formation, which in turn stimulated trade.


Thus, as trade increased along the Niger and into adjoining areas, so did social complexity. Did this new environment select for cognitive ability? Piffer (2021, see Figure 7) calculated the polygenic scores of alleles associated with educational attainment for several West African populations. Mean cognitive ability seems to increase as one goes from west to east. The polygenic score is lowest for the Mende (Sierra Leone) and progressively higher for Gambians, the Esan (Nigeria), and the Yoruba (Nigeria). The Yoruba have almost the same polygenic score as do African Americans, even though the latter have about 20% European admixture.


Igbo achievement


It’s a pity that we have no polygenic data on the Igbo (formerly the Ibo), who live near the mouth of the Niger and seem to have gone the farthest on this trajectory of cognitive evolution. Indeed, they excel academically:


The superior Igbo achievement on GCSEs is not new and has been noted in studies that came before the recent media discovery of African performance. A 2007 report on "case study" model schools in Lambeth also included a rare disclosure of specified Igbo performance […] and it confirms that Igbos have been performing exceptionally well for a long time (5 + A*-C GCSEs); in fact, it is difficult to find a time when they ever performed below British whites. (Chisala 2015)


In addition to high cognitive ability, the Igbo are said to have a different mindset: “the Ibo have a greater achievement motivation and are more willing to explore new avenues of power than either the Yoruba or the Hausa.” They have “a general belief in the possibility, indeed necessity, of manipulating one’s world; of determining one’s own destiny; of ‘getting up’ in the world” (Slater 1983).


By the time of Nigerian independence, these characteristics had made the Igbo a dominant force in the country’s life:


All over Nigeria, Ibos filled urban jobs at every level far out of proportion to their numbers, as laborers and domestic servants, as bureaucrats, corporate managers, and technicians. Two-thirds of the senior jobs in the Nigerian Railway Corporation were held by Ibos. Three-quarters of Nigeria's diplomats came from the Eastern Region. So did almost half of the 4,500 students graduating from Nigerian universities in 1966. (Baker 1980)


The Igbos were nonetheless a minority within Nigeria, a fact reflected in the leadership that took over after independence. That leadership was resented by the Igbo, who saw it not only as beyond their control but also as corrupt, incompetent, and fraudulent. In 1966, a group of Igbo officers carried out a coup d’état and executed the Prime Minister, the Premier of the Northern Region, and the Premier of the Western Region. There then followed a counter-coup and a wave of persecution that led to the deaths of 8,000 to 30,000 Igbo and the exodus of between one and two million to their homeland in the Eastern region. When the Igbo learned that the new government would fragment their region into three parts, they revolted and declared their independence. Thus began the Nigerian Civil War (1967-1970).


Henry Kissinger (1969) summed up the situation in a memorandum to President Nixon: “The Ibos are the wandering Jews of West Africa — gifted, aggressive, Westernized; at best envied and resented, but mostly despised by the mass of their neighbors in the Federation.”


If we go back to the eighteenth century, and to the earliest European observations, we see that the Igbo were already viewed as “competitive, individualistic, status-conscious, antiauthoritarian, pragmatic, and practical—a people with a strongly developed commercial sense” (Mullin 1994, p. 286). West Indian slave-owners saw them as adept at learning English. “In Jamaican descriptions of all named peoples, Ibo were the most adroit in using language distinctively and in some instances deceptively” (Mullin 1994, pp. 286-287).


In general, cognitive ability seems to be higher in populations that specialize in trade, since the cognitive demands are likewise higher. The Igbo specialized in trade at an early date, thanks to their location on the Niger Delta and their role as middlemen in exchanges between the coast and the interior (Frost 2015).




Baker, P.H. (1980). Lurching toward unity. The Wilson Quarterly, 4, 70-80.  


Chisala, C. (2015). The IQ gap is no longer a black and white issue. The Unz Review, June 25.


Frost, P. (2015). The Jews of West Africa?  Evo and Proud, July 4.


Kissinger, H.A. (1969). Memorandum, January 28. U.S. Department of State Archive.  


McIntosh, S.K., and R.J. McIntosh. (1988). From stone to metal: New perspectives on the later prehistory of West Africa. Journal of World Prehistory 2(1): 89-133.


Mullin, M. (1994). Africa in America: Slave Acculturation and Resistance in the American South and the British Caribbean, 1736-1831. University of Illinois Press.


Piffer, D. (2021). Divergent selection on height and cognitive ability: evidence from Fst and polygenic scores. OpenPsych   


Slater, R. (1983) Bureaucracy, Education and The Ibo: A Review. Journal of Educational Administration and History 15(1): 46-49.

Monday, March 28, 2022

Cognitive ability of indigenous Arctic peoples


In cold environments, human cognitive ability was an adaptation not to resource scarcity, as is often claimed, but to an abundance of resources that could be exploited only through a high level of planning, coordination, and tool development.

Caribou on Thelon River (Wikicommons – Cameron Hayne)



A reader has asked me, via Twitter: “Do you have any articles as to why the IQ of Siberian and Inuit peoples is lower than Northern Europeans despite similarly cold climate?”


Actually, indigenous Arctic peoples seem to be close to the global maximum of cognitive ability. It is also true, however, that the maximum is at more temperate latitudes, specifically within two broad regions:


·         East Asia – this is a “plateau” of populations with consistently high mean IQ, i.e., Chinese, Koreans, and Japanese. For Unz (2013), this plateau arose during the time of recorded history through the upper classes continually replacing the lower classes: “Each generation, the poorest disappeared, the less affluent failed to replenish their numbers, and all those lower rungs on the economic ladder were filled by the downwardly mobile children of the fecund wealthy.” A secondary cause was the imperial examination for civil-service jobs: "in China the proud family traditions would boast generations of top-scoring test-takers, along with the important government positions that they had received as a result."


·         Europe – this second plateau likewise arose during the time of recorded history, at first slowly during antiquity and then more rapidly during the late medieval to early modern period (Clark 2007; Woodley 2017). The latter increase was driven by expansion of the middle class, particularly by craftspeople who participated in the proto-industrial revolution of the 15th to early 19th centuries. There are thus “peaks” in the plateau, notably Ashkenazi Jews and the descendants of cottage-industry communities in Ulster, Lancashire, Yorkshire, Brittany, Flanders, Alsace, Westphalia, Saxony, the Zurich uplands, the Piedmont, and Lombardy (Cochran et al. 2006; Dunkel et al. 2019; Frost 2007; Piffer 2019; Seccombe 1992, pp. 205-217). Those communities contributed disproportionately to European population growth through early marriage and high childbearing, thus changing Europe’s cognitive landscape (Seccombe 1992, pp. 205-217). 

      The fatalism of serfs gave way to the rationalism of craftspeople: "The life-choices that structure family continuity through time had more predictable consequences; critical objectives could be achieved more regularly. Increasingly, the problem of uncontrolled randomness in life's fortunes was addressed through the calculus of probabilities, rather than through ritual, prayer, pleas for divine intercession, and stoicism ..." (Seccombe 1992, p. 212). 

There is another high-IQ peak among the Finns (Piffer 2019), for reasons that remain uncertain (Late transition from hunting to farming? Absence of serfdom?).


If cold climates select for cognitive ability, why do we find maximum cognitive ability at temperate latitudes? This is the apparent contradiction I address in my 2019 paper. In short, I argue that cold climates selected for cognitive ability only when humans were hunter-gatherers. This selection was driven not by resource scarcity, as is often claimed, but rather by an abundance of resources that could be exploited only through a high level of planning, coordination, and tool development (Frost 2019). With the advent of farming, and increasing social complexity, the pressure of selection shifted southward to environments that imposed new cognitive challenges: literacy and numeracy, state formation, laws and law enforcement, social stratification, expansion of the built environment, growth of music, literature, and the fine arts, development of religious beliefs and practices, construction of roads and other infrastructures, and so on.


This cognitive evolution initially went farther in the Middle East. Then, sometime around the 16th century, that region seemed to hit a ceiling as the pace of social complexification slowed down. The slowdown had several causes. First, there was demographic stagnation and loss of food production, due to the cumulative effects of erosion, salinization, and overgrazing. Second, there were ideological constraints. Although Islam was not alone in seeking to limit the free expression of ideas, it was more effective than Christianity in preventing the rise of a secular intellectual class that could spur progress in science and technology. Third, a true market economy failed to develop in the Middle East. The concept of trade was widely understood, but production of goods and services remained mostly within the household, i.e., family members, servants and, more broadly, relatives and in-laws. As a result, the market could not replace kinship as the main organizing principle of society.


Finally, and perhaps most importantly, cognitive evolution continued in Europe and East Asia because their lower classes were continually replaced, demographically, by their middle and upper classes. This process, described by Gregory Clark for England and Ron Unz for China, has three key elements:


1. Social class correlates positively with IQ.


2. Social class correlates positively with reproductive success. Lower classes fail to reproduce themselves, whereas higher classes more than reproduce themselves.


3. There are no barriers to downward social mobility. Lower classes are thus continually replaced by the demographic overflow of higher classes (Clark 2007; Unz 2013).


These three elements are not universal. Hunter-gatherers and simple farming societies have little or no social stratification. Other societies are stratified but have no State that can monopolize the use of violence. There is instead an ongoing free-for-all that selects for ruthlessness, charisma, and the ability to mobilize male violence. Finally, some societies are so stratified that downward mobility is impossible. Social classes are permanent “castes.”


In sum, cognitive evolution was initially driven by cold climate at higher latitudes and later by increasing social complexity at lower latitudes. Some higher-latitude groups then moved south to exploit the opportunities being created by increased social complexity. Those groups were not the ones who initiated the transition to farming, sedentism, and social complexity. Instead, they arrived after the fact, being cognitively pre-adapted for the opportunities that others had created and thus better able to pursue this evolutionary trajectory (Frost 2019).


Studies of cognitive ability in Arctic peoples


To return to the original question, indigenous Arctic peoples seem to be close to the global maximum of cognitive ability, but the evidence is limited and questionable. This situation has three causes:


·         Difficulties in administering IQ tests to people who are unfamiliar not only with modern concepts but also with the modern question-and-answer paradigm. Traditionally, indigenous Arctic people learn not by asking questions but by observing a “master” and then copying whatever he or she does. Asking questions can also be impolite, especially if too many are asked in rapid succession. I should point out that the same difficulties used to exist in Western societies. People in Britain and North America were unfamiliar with standardized written tests until the rise of publicly funded schools and competitive civil-service exams in the late 19th century (Wikipedia 2022). It wasn’t because people got smarter that mean IQ rose during the 20th century. They just got better at taking tests.


·         Ideological constraints. IQ research was discouraged in the Soviet Union, partly because of the dominant belief in environmental determinism and partly because of a desire to avoid stigmatizing certain national groups. A ban on intelligence testing was thus imposed in 1936 and gradually lifted only in the 1960s and early 1970s (Grigoriev and Lynn 2009).


·         Lack of research on alleles associated with educational attainment. This avenue of research offers a better measure of innate cognitive ability but is still in its infancy with respect to Arctic peoples. I know of only one relevant study. Piffer (2013) found that the Met allele at COMT, a gene linked to executive function, working memory, and intelligence, is more frequent in farming societies than in hunter-gatherers, with one interesting exception: "hunter-gatherers living at high latitudes (Inuit) show high frequencies of the Met allele, possibly due to the higher pressure on technological skills and planning abilities posed by the adverse climatic conditions near the North Pole."



Siberia (Evenk, Altai, Yakuts)


In Siberia, IQ tests were conducted in 1929 and later in 2015-17. The first period saw testing among the Evenk of the northeast and the Altai of the south.


When a Binet test was administered to 5 Evenk children 7 to 19 years old, the mean score was 70.16. The study’s author reported that the children had trouble understanding units of measurement and number.


He reported that when Evenk children were questioned about devices for measurement, they did not have the concept of an absolute unit of measurement. They thought that the unit changed with the material measured. Bulanow [the author] reported further that when he asked Evenk adults how many children they had “It was difficult, almost impossible, to get from parents precise information as to how many of their children were alive, how many of their children had died, what was the age of their children, and so on.” (Grigoriev and Lynn 2009, p. 449)


When a Binet test was administered to 52 Altai children 8 to 20 years old, the mean score was 66.9. Again, the subjects had problems with units of measurement: “when they were questioned about the length of a meter, the Altai would often ask: “Which meter?” They thought that the meter in one shop could be longer than in another” (Grigoriev and Lynn 2009, p. 450). Nonetheless, adult Altai showed remarkable aptitudes in other areas of life:


Although adult Altai performed calculations poorly at the time of study, they showed a remarkable ability for visual estimation of large quantities. A herdsman, who could count only to 20–30, noticed very well the absence of one horse, cow or sheep in a herd of many hundreds. He looked at a huge herd and noted that a particular cow was absent. Another example of the great visualization ability of the Altai was that they could remember and showed the way through wild territory, where they had been only once many years previously (Grigoriev and Lynn 2009, p. 450)


In recent years, there has been a renewed effort to study cognitive ability among indigenous Siberian peoples:


·         Shibaev and Lynn (2015) tested 29 Evenk children and found a mean score of 80. Also tested were 13 ethnic Russian children, who had grown up under similar conditions. Their mean score was 85.

·         Shibaev and Lynn (2017) tested 287 Yakut children and 52 ethnic Russian children from eastern Siberia. The mean score was 97.0 for the Yakuts and 97.9 for the ethnic Russians.

·         Shibaev et al. (2020) tested 518 Yakut children and 956 ethnic Russian children. The age range was wider than in previous studies, and the IQ difference between the two groups seemed, in general, to be greater at younger ages than at older ones. At 9 years of age the Russians had a 3 point advantage over the Yakuts, whereas at 17 this advantage was zero. Yakut children may have a slower rate of cognitive maturation. There is also some doubt as to the comparability of the two groups, since the Russians came largely from a city (Tomsk), while the Yakuts came from a city (Yakutsk) and a small town (Vilyuysk).


The authors note that the differences between ethnic Russians and indigenous Siberians can be largely explained by an urban-rural divide:


[…] for both Russians and Yakuts the IQs of the city samples were higher than the IQs of the village samples. For the Russians, there was a difference of 10.5 IQ points between the combined city samples and the village sample, while for the Yakuts the difference was 4.4 points. The higher IQs of the city samples is a common result found in many previous studies reporting that urban populations typically obtain higher IQs than rural populations. (Shibaev and Lynn 2017)


Shibaev and Lynn (2017) attribute this urban-rural divide to differential migration: smarter people move to the city, and dumber people stay home in the village. I would argue that villagers are less familiar with modern concepts and the modern question-and-answer paradigm.


Arctic North America (Inuit)


Like indigenous Siberians, the Inuit (Eskimos) display an unusual ability to find their way across vast expanses of territory, a task that requires remembering huge amounts of visuospatial data. Adults are reported to have an "extraordinary ability to find their way through what appears to be a featureless terrain by remembering visual configurations [...]. According to some reports, such memories persist for long periods of time. Elderly hunters have succeeded in guiding parties through terrain seen only in their youth" (Kleinfeld 1973, p. 344)


Nonetheless, Inuit have done poorly in most IQ studies, especially in older studies of traditional Inuit. Kleinfeld (1973) cites several reasons:


Unfamiliarity with test-taking:

Eskimos' performance on standardized tests may be lowered because of their unfamiliarity with test-taking conventions and because of cultural biases of the tests. Eskimos, for example, may find it difficult to view a trivial, pointless task such as copying a design or running through a finger maze as worthy of serious concentration and maximum effort.


Racial context of test-taking

Eskimos, especially young males, have become increasingly antagonistic to any sort of testing and research, which they view as another form of White exploitation. Co-operation, if given at all, may be perfunctory, resulting in extremely low test scores.


Extreme caution during test-taking

Eskimos, especially males, have been socialized into extreme caution before making a judgment. The hunter is taught never to take risks, never to call out a hasty evaluation because the penalty can be swift death not only for himself but also for others who rely on his decision. […] Especially more traditional Eskimos tend to have a slow, cautious response style which may depress their scores on speeded figural tests.


Slower rate of cognitive maturation

[There is] some evidence that Eskimos' peak performance on figural tests occurs later than that of Western groups. [This] raises the possibility of a slower rate of cognitive maturation among Eskimos which would be consistent with their somewhat slower rate of physical maturation […]. If this is the case, the usual age-matched comparisons between Western and Eskimo children on figural tests may be misleading.


In their reviews of the literature, Kleinfeld (1973) and Taylor and Skanes (1976) note that Inuit generally outperform Whites on visual discrimination and spatial tests. Interestingly, Inuit children do almost as well as non-Inuit children on English spelling tests while doing poorly in other aspects of English, perhaps because they memorize the shapes of words. On the other hand, they underperform White children on verbal-educational and inductive reasoning tests. The latter finding may reflect lack of familiarity with English in earlier studies. When Taylor and Skanes (1976a) tested Inuit and White first graders for vocabulary and arithmetic, using the Wechsler Pre-School and Primary Scale of Intelligence, they found no significant differences between the two groups in spatial, verbal-educational, and inductive reasoning abilities. When the same researchers tested a larger sample of Inuit and White children from different age groups, using a series of digit span tests and Raven’s progressive matrices, they found that the Inuit children caught up with the White children with increasing age on the digit span tests and that the Inuit children outperformed the White children on the Raven’s progressive matrices (Taylor and Skanes 1976b).


Wright et al. (1996) tested the IQ of Inuit children in Arctic Quebec during the first two grades of school, using Coloured Progressive Matrices (CPM). Mean scores were consistently higher than age-appropriate U.S. norms and were comparable with data for White children in southern Quebec. In addition, the scores of children with two Inuit parents did not differ significantly from those of children with mixed Inuit/White heritage. 


Nonetheless, Inuit children do worse at school than other children, having not only lower rates of academic achievement but also higher dropout and suicide rates. For Clifton and Roberts (1988), the reason is inferior self-perception of their ability and less active involvement in the educational process. This mindset may be rooted in the traditional Inuit attitude toward education, where the “student” simply observes and copies the “master.”


In sum, the Inuit seem to have about the same level of cognitive ability as people of European origin, with perhaps some interesting differences: superior visuospatial skills, higher risk aversion, slower cognitive maturation, and a more imitative and less inquisitive approach to learning. It is still unclear whether they have lower verbal-educational and inductive reasoning abilities. In their review, McShane and Berry (1988, p. 392) conclude that indigenous Arctic peoples do well relative to Euroamerican norms, showing “high performance on both piagetian and psychometric tests of visually based spatial, analytic, disembedding, and inductive abilities.” The two researchers attribute reports of lower verbal ability to second-language familiarity with the test language. Clearly, more research is needed, if only to adapt the northern educational system to Inuit needs.


It must be said that the Inuit are ill-suited to the Western model of education and, more broadly, to the Western model of sedentism, individualism, and asociality. Young Inuit feel useless in that kind of society, and all too many end up committing suicide.


Conclusion and discussion


We have only a few studies of cognitive ability among indigenous Arctic peoples. This paucity is due only in part to methodological problems. In the Soviet Union, all IQ research ceased between 1936 and the 1960s. It has recommenced among indigenous Arctic peoples only over the past decade. Meanwhile, similar research in Canada and the U.S. has been nonexistent since the 1990s.


If we look at the existing research, we may doubt whether the subjects were fully familiar with test-taking and the modern question-and-answer paradigm. Another problem is that indigenous Arctic children seem to have a slower rate of cognitive maturation. If Yakut subjects are still catching up to Russian subjects at the age of 17, it might be more appropriate to compare the two groups at an older age. In practice, this would be difficult because young adults start following different life paths after 17. Finally, indigenous Arctic peoples may allocate their mental capacities differently, being better, for instance, at processing visuospatial data than other kinds of information. Since IQ tests have been designed for Western children, the test design may not correspond to the mental tasks that some non-Western groups prioritize.


Yes, dear reader, I hear you. If people do well on one cognitive task, they should do well on all others, shouldn’t they? Isn’t that what the g factor is all about? In other words, people will tap into the same mental capacity for any cognitive task.


The relative strength of the g factor, however, has been calculated from subjects in Western or Westernized societies. Does it have the same strength across different mental domains among people who until recently were nomadic hunters? Anthropologists, like John Berry, have argued that hunters allocate much more of their mental capacity to visuospatial orientation:


Hunters, by this way of thinking, require good visual acuity, keen disembedding skills and a well-developed sense of spatial orientation. To hunt successfully, the hunter must be able to discern the object of the quest (which is often embedded in a complex visual landscape), then disembed the object, and finally return to home base. In contrast, agriculturalists need not develop these particular skills, but rather they need to invest in other areas of development, such as conservation (in both the economic and the Piagetian senses) and close social interactions. (Berry 2008, p. 3)


It would be interesting to find out whether these skills have become hardwired to some degree through gene-culture coevolution. Are hunting peoples inherently better at orienting themselves in space? Did vast expanses of land favor the success of people who could more easily find their way across vast expanses of land? To answer that question, John Berry launched a project in the late 1980s with the geneticist L.L. Cavalli-Sforza. They wished to recruit participants among the Inuit of northern Canada and use aptitude for soapstone carving as a means to measure visuospatial skills:


With most individuals having had a reasonably fair chance and stimulation to become artists, one is in a better condition to study possible genetic factors contributing to artistic talent, if any. Another great advantage of carrying out this study among the Inuit is the frequency with which adoptions (also early ones, at birth) occur in this population. Frequencies of adoptions reported during the meeting varied from 15% to 30%. Adoptions allow one to distinguish cultural from biological inheritance by studying correlations of adopted children with foster relatives on one hand and biological relatives on the other. (Berry and Cavalli-Sforza 1986)


Cavalli-Sforza was thinking, here, along the lines of gene-culture coevolution. He had in fact been one of the founders of that paradigm, although he preferred the term “dual inheritance theory.” Now, he would have a chance to investigate it in the field.


Then, suddenly, he backed out of the project. For “health reasons.” Yet neither his biography nor his autobiography mentions any health problems during that period of his life.





Berry, J.W. (2008). Models of Ecocultural Adaptation and Cultural Transmission: The Example of Inuit Art, paper presented at the conference Adaptation et socialisation des minoritiés culturelles en région, June 3-4, Quebec City.


Berry, J.W., and L.L. Cavalli-Sforza. (1986). Cultural and Genetic Influences on Inuit Art. Report to the Social Sciences and Humanities Research Council of Canada, Ottawa.


Clark, G. (2007). A Farewell to Alms. A Brief Economic History of the World. Princeton University Press, Princeton and Oxford


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Seccombe, W. (1992). A Millennium of Family Change. Feudalism to Capitalism in Northwestern Europe. London: Verso.


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