African migrants at the
Egyptian-Israeli border (Wikicommons)
During most of the twentieth
century people did better and better on IQ tests. This increase, dubbed the
Flynn effect, is now plateauing in the Western world. It is even reversing in
Scandinavia and France (Bratsberg and Rogeberg 2018; Dutton and Lynn 2015; Flynn
2007, p. 143; Teasdale and Own 2005).
A similar plateauing and even
reversal has begun in the Arab world. In Kuwait, mean IQ fell an average of 6.2
points between 2006 and 2015 (Dutton et al. 2017a). In Damascus, it remained
unchanged between 2004 and 2013/14 (Dutton et al. 2018a). In Khartoum, it fell
an average of 2.13 points between 1999 and 2010 (Dutton et al. 2017b).
Khartoum: is the Flynn effect continuing?
The authors of the Khartoum
study later retracted their finding, however. Because the earliest data had
been collected just before the introduction of compulsory schooling in 1999, the
IQ decline could simply reflect a change in sampling: from middle-class children
to children in general. There were also strange age differences: IQ scores
declined in some age groups but not in others. So the authors conducted a
second study, examining only data from students with a compulsory schooling
background. They now found an increase in mean IQ from 2004 to 2016, i.e., a
positive Flynn effect (Dutton et al. 2018b).
On the other hand, “compulsory
schooling background" may also mean a different ethnic background. When I
enquired about this point, Dr. Bakhiet replied that the study was done in
residential areas of Khartoum where there were no refugees or immigrants. The participants
thus “represent the people of northern Sudan” and were not recruited from among
the millions of migrants who live on the city’s outskirts.
As for the first Khartoum
study, we know little about the ethnic background of the participants. Some of
them seem to have had migrant backgrounds. We should keep in mind that many refugees
were initially housed within the city limits and that not all migrants ended up
in refugee facilities. Unfortunately, it would be difficult to find out more
because the lead researcher, Dr. Omar Khaleefa, was abducted and apparently
murdered in 2012. I suspect that this kind of information was not recorded at
the time, given the delicate nature of ethnic identity in Sudan.
In sum, the second Khartoum
study largely excludes the city’s immigrant population, and it is this study
that provides a reassuring picture of rising IQ. As for the first Khartoum
study, we know less about the ethnic makeup of its participants, particularly
whether their ethnic makeup changed over time. This is an important factor to
consider. Khartoum is now overwhelmingly a city of migrants from the south, and
it is unlikely that many will ever return home.
Possible causes
Why this apparent plateauing
or reversal in places as different as Khartoum, Kuwait, and Damascus? The
authors cite several possible causes:
Emigration, i.e., 'brain drain'
Damascus has lost many
educated people because of the civil war. There has been much less of a brain
drain in Khartoum and probably none at all in Kuwait.
Muslim curriculum
Both Sudan and Kuwait have
introduced a "Muslim curriculum" that focuses on teaching Islam to
the relative exclusion of scientific subjects. Damascus students get only two
hours of religious education per week.
Differential fertility
This factor has been studied
in three Arab countries: Kuwait, Libya, and Sudan. When IQ is compared with
number of siblings, there is hardly any correlation in Kuwaitis but a
significant negative correlation in Libyans and Sudanese (Abdel-Khalek and Lynn
2008; Al-Shahomee et al. 2013; Khaleefa 2010). Khaleefa (2010) calculated that
Sudanese IQ is declining at a rate of 0.8 points per generation because higher
IQ individuals have smaller families. This factor may be stronger in Turkey,
Lebanon, and Egypt, which are more Westernized.
Immigration
The Khartoum Metropolitan Area
grew from 2.9 million in 1993 to 5.3 million in 2008. This growth was driven
overwhelmingly by migration from South Sudan and Darfur, largely as a result of
the Second Sudanese Civil War (1983-2005). As a result, “southern” migrants now
make up a majority of the population:
This war led to an influx of displaced persons coming into Khartoum from the provinces and from South Sudan, now a separate state. The average IQ of Arab Sudanese with no refugee background around Khartoum has been found to be 77.4, based on UK norms. However, the average IQ of people from the war-torn region of Darfur, which is still within the current Sudanese state, is roughly 64 (Bakhiet & Lynn, 2015). This is similar to IQ estimates for the Southern Sudanese (e.g. Fahmy, 1964, cited in Lynn, 2006), many of whom also fled to Khartoum during the war (Bassil, 2013). Indeed, the genetics of the northern Sudanese is very close to that of Egypt and other North African countries. By contrast the West and south of the country are genetically closer to the Sub-Saharan Africans of South Sudan. (Dutton et al. 2017b)
Meanwhile, Kuwait became more
South Asian during this same period. The IQ surveys in 2006 and 2015 thus sampled
two significantly different populations:
In 1975, Jordanians and Palestinians were the predominant category comprising about 40 % of the total non-Kuwaiti population, followed by about 12 % Egyptians and 9 % Iraqis. Asians from Iran, India and Pakistan constituted only about 18 % of the non-Kuwaiti population. The Asian presence in Kuwait increased significantly during the late 1970s and early 1980s, resulting in 35 % of the non-Kuwaitis being Asian. After liberation of Kuwait, the percentage of Asians increased further and in 1995, Arabs and Asians each constituted about half of the total non-Kuwaiti population. During the decade of 1995-2005, Arabs lost ground to Asians with the latter comprising almost 59 % of the non-Kuwaiti population in 2007. (Shah 2007)
The Simber Effect
The above studies also show
that IQ begins to decline during adolescence in these countries. In people of
European origin the decline normally happens later in life:
The second point of interest is that in both samples the SPM score is statistically significantly lower among 18 year olds than it is among 17 year olds. In general, overall performance on IQ tests tends to increase into adulthood, meaning that we would expect 18 year olds to score higher than17 year olds. In this regard, Bakhiet et al. (2018) have identified what they have called the Simber Effect in a meta-analysis of progressive matrices administrations in 12 Arab countries. They found that IQ in Arab countries, relative to European norms, falls between the ages of 7 and 18, when looking within single cohorts. At age 7 it is the same or slightly below European norms but it eventually falls to around a standard deviation below European norms. They have shown this by comparing different cohorts divided up age, not via a longitudinal analysis of one cohort. The raw score declines at this very specific age that we have observed here would be potentially consistent with this gradual fall and they are not unique to Syria. Xhosa SPM score declines between 15 and 16 (Bakhiet & Lynn, 2015). Jordanian Advanced Progressive Matrices score peaks at 18 to 20 and then slowly declines (Lynn & Abdel-Khalek, 2009). In Sudan, SPM score peaks at 17 and then falls (Khaleefa, Lynn, Abulgasim, Dossa, & Abdulraddi, 2010) while in Somalia it also declines after the age of 17 (Bakhiet et al., In press). (Dutton et al. 2018a).
The ability to learn may have originally been a juvenile trait in our species. Childhood was a time when early humans had to learn what to do and what not to do. After puberty, they literally became set in their ways. As societies became more complex, adults had to retain this ability, in the same way they have retained the ability to digest milk sugar wherever dairy farming is practiced.
Conclusions
IQ has recently declined in
parts of the Arab world, and several possible causes have been put forward.
More research is needed but the following conclusions seem justified:
- Ethnic change is a major
cause, if not the leading one. Although we speak of the 'migrant crisis' as a
European problem, it is actually part of a larger demographic overflow from
sub-Saharan Africa and South Asia, and this overflow is primarily spilling into
North Africa and the Middle East.
- Differential fertility,
commonly called dysgenics, is becoming important, at least in some Arab
countries. This may be due to Westernization. The upper and middle classes are
more likely to follow Western models of behavior, including smaller family
size. This is at most a secondary cause of declining IQ in the Arab world.
- The introduction of a
'Muslim curriculum' may or may not be a factor. Its effects on IQ should be
studied in a stable Arab population that is not changing through immigration or
emigration.
- The Flynn effect may be
running out of steam in the Arab world, as it has in the Western world. Other
trends are thus becoming visible, and those trends are largely negative.
In itself, the end of the Flynn
effect is no cause for worry. It probably does not correspond to a real
increase in cognitive ability. People have simply become more adept at taking
tests, including IQ tests.
Just think. Beginning at least
in the 1930s the Flynn effect added around 3 points each decade to average IQ
until the 1990s. Such a huge gain—18 points—should be visible in the evolution
of popular culture. Yet popular culture didn't become higher-brow during that
period. In fact, from the 1970s onward it became lower-brow. In magazines,
fonts became bigger and sentences simpler and shorter. In movies and sitcoms,
plots became less complex, and characters shallower. You could counter-argue
that popular culture was now embracing the interests of ordinary people, after
long being elitist, but that isn't my impression. In the 1970s I often met
ordinary adults with intellectual hobbies of one sort or another, like stamp
collecting, ham radio, science fiction, field naturalism, astronomy, and so on.
My father had a working-class background, yet he had all the works of Ray
Bradbury, plus earlier works by H.G. Wells and Jules Verne. Ordinary people
like that are now hard to find, even though IQ scores have risen considerably
between then and now.
This is another reason why, in
the nature versus nurture debate, twin studies overestimate the latter's
importance. "Nurture" is simply the residue of everything that's not
nature: not only your learning environment but also your familiarity with
test-taking, as well as errors in calculating test scores or differences in
scores due to the way the tests are administered.
On a final note, we need more
research on IQ in the Arab world. Unfortunately, there, as here, such research
is not without risk. Omar Khaleefa, at the University of Khartoum, did many
pioneering studies on this subject in Sudan, including his calculation that
Sudanese IQ is declining at a rate of 0.8 points per generation. He disappeared
six years ago. His body was never found, and no demands for money were ever
made, as is usually the case with abductions. His family holds the government
responsible:
Professor Omar Haroon Al Khaleefa left his home in an upscale neighborhood of Khartoum North and was never seen again. His family holds the Sudanese authorities responsible for his disappearance, saying they have failed to investigate new information that has come to light. (Abdin 2014)
Please note:
I may or may not be posting
over the next three months. This is a temporary situation, and I will resume
regular posting in November.
References
Abdel-Khalek, A.M., and R.
Lynn. (2008). Intelligence, family size and birth order: Some data from Kuwait.
Personality and Individual Differences
44: 1032-1038.
Abdin, T. (2014). Sudan: The Case of the Missing Professor. AllAfrica, May 22
Al-Shahomee, A.A., R. Lynn,
and S.E. Abdalla. (2013). Dysgenic fertility, intelligence and family size in
Libya. Intelligence 41(1): 67-69.
Bratsberg, B., and O.
Rogeberg. (2018). Flynn effect and its reversal are both environmentally
caused. Proceedings of the National
Academy of Sciences Jun 2018, DOI: 10.1073/pnas.1718793115
Dutton, E., and R. Lynn.
(2015). A negative Flynn Effect in France, 1999-2008-9. Intelligence 51: 67 -70.
Dutton, E., S. Bakhiet, Y.
Essa, T. Blahmar, and S. Hakami. (2017a). A negative Flynn effect in Kuwait:
The same effect as Europe but with seemingly different causes. Personality and Individual Differences 114:
69 -72.
Dutton, E., S. Bakhiet, K.
Ziada, Y. Essa, and T. Blahmar. (2017b). A negative Flynn Effect in Khartoum,
the Sudanese capital. Intelligence 63:
51 -55.
Dutton, E., Y.A.S. Essab, S.F.
Bakhietb, H.A.A. Alib, S.M. Alqafarib, A.S.H. Alfalehb, and D. Becker. (2018a).
Brain drain in Syria's ancient capital: No Flynn Effect in Damascus,
2004-2013/14. Personality and Individual
Differences 125: 10-13
Dutton, E., S.F.A. Bakhiet,
H.A. Osman, D. Becker, Y.A.S. Essa, T.A.M. Blahmar, R. Lynn, and S.M. Hakami
(2018b). A Flynn Effect in Khartoum, the Sudanese capital, 2004-2016. Intelligence 68: 82-86.
Flynn, J.R. (2009). Requiem
for nutrition as the cause of IQ gains: Raven's gains in Britain 1938-2008. Economics & Human Biology 7(1):
18-27.
Flynn, J.R. (2007). What is Intelligence? Beyond the Flynn
Effect. Cambridge University Press.
Khaleefa, O. (2010).
Intelligence in Sudan and IQ gain between 1964 and 2008. ArabPsyNet E-Journal 25-26: 157-167.
Shah, N.M. (2007). Migration to Kuwait: Trends, Patterns and Policies. Paper
Prepared for the Migration and Refugee Movements in the Middle East and North
Africa. The Forced Migration & Refugee Studies Program. The American
University in Cairo, Egypt. October 23-25, 200
Teasdale, T.W., and D.R. Owen.
(2005). A long-term rise and recent decline in intelligence test performance:
The Flynn Effect in reverse. Personality
and Individual Differences 39(4): 837-843.
