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.