| I graduated in psychology and took my Ph.D.
at the University of Cambridge and have worked as lecturer in psychology
at the University of Exeter, professor of psychology at the Economic
and Social Research Institute, Dublin, and at the University of
Ulster.
Most of my work has been on intelligence. My
major discoveries are that the Oriental peoples of East Asia have
higher average intelligence by about 5 IQs points than Europeans
and peoples of European origin in the United States and elsewhere;
and that men have a higher average IQ than women by about 5 IQs
points. I first published the high IQ of the Oriental peoples in
1977 in a paper on the intelligence of the Japanese. In subsequent
years the high Oriental IQ has been confirmed in numerous studies
of Oriental peoples in Hong Kong, Taiwan, South Korea, China, Singapore
and the United States.
In 1983 I published a paper in Nature showing
that the IQ in Japan had increased over the course of the previous
half century, a phenomenon now known as the Flynn Effect following
the demonstration by Jim Flynn of secular increases in intelligence
in number of countries. In 1989 I proposed that the increases in
intelligence have been caused by improvements in nutrition. I have
also published several papers showing that intelligence is associated
with brain size and reaction times.
My work on intelligence and brain size led me to consider the
problem that women have smaller brains than men even when allowance
is made for their smaller bodies. This implies that men should
have higher average IQs than women, but it has been universally
asserted that men and women have equal average IQs. In 1994 I proposed
that the solution to this problem is that girls mature faster than
boys and this compensates for their lower IQs, which only appear
at the age of 16 onwards. Among adults men have higher average
IQs than women by about 4 IQ points. This advantage consists largely
of higher spatial abilities but is also present in non-verbal reasoning.
In two meta-analyses of sex differences on the Progressive Matrices
carried out with Paul Irwing (2004, 2005) we showed that in the general
population men have a higher IQs than women by 5 IQ points, and in university
students the advantage of men is 4.6 IQ points.
In
1991 I extended my work on race differences in intelligence to
other races. I concluded that the average IQ of blacks in sub-Saharan
Africa is approximately 70. It has long been known that the average
IQ of blacks in the United States is approximately 85. The explanation
for the higher IQ of American blacks is that they have about 25
per cent of Caucasian genes and a better environment.
The theory I have advanced to explain these race differences
in IQ is that when early humans migrated from Africa into Eurasia
they encountered the difficulty of survival during cold winters.
This problem was especially severe during the ice ages. Plant foods
were not available for much of the year and survival required the
hunting and dismembering of large animals for food and the ability
to make tools, weapons and clothing, to build shelters and make
fires. These problems required higher intelligence and exerted
selection pressure for enhanced intelligence, particularly on the
Orientals.
My book Dysgenics (Westport, CT: Praeger, 1996)
showed that the eugenicists were right in their belief that modern
populations have been deteriorating genetically in respect of health,
intelligence and the personality trait of conscientiousness. This
deterioration began in the second half of the 19th century and
has continued up to the present.
My book Eugenics (Westport, CT: Praeger, 2001)
considers what measures could be taken to rectify this and discusses
the genetic future of mankind. It is argued that genetic improvement
is likely to evolve spontaneously through the technique of embryo
selection in which women will use IVF to grow a number of embryos,
have them genetically assessed and will select for implantation
those with genetically desirable qualities. It is also likely that
some authoritarian states will use genetic engineering to improve
the genetic quality of their populations for military purposes.
My book IQ and the Wealth of Nations (co-author
Tatu Vanhanen of the University of Helsinki) (Westport, CT: Praeger,
2002) considers the problem of national differences in wealth and
economic growth. Economists and other social scientists have been
trying to solve the problem of why some nations are so rich and
others so poor since Adam Smith’s The
Wealth of Nations (1776). We argue that an important
but hitherto unrecognised factor is the IQs of the populations.
We give measures and estimates of average IQs in the world’s 185 nations and show that national IQs
are strongly related to national incomes and rates of economic growth. The
principal reason for this is that nations whose populations have high IQs can
produce goods and services that command high values in international markets. See
below for more details of this argument and on the IQs of every
nation in the world.
My most recent book published in 2006 is Race Differences
in Intelligence: An Evolutionary Analysis. Atlanta, Georgia: Washington
Summit Books (PO Box 3514, Augusta, GA 30914) ISBN 1-59368-020-1 pp.
318., US$37.95 HB), $20.95 (PB) (plus $6 for overseas orders).
A
review by Prof.J.P.Rushton in Personality and Individual Differences is
given below.
Lynn’s book represents the culmination of more
than a quarter of a century’s work on race differences in
intelligence. It was in 1977 that he first ventured into this field – some
would say minefield – with the publication of two papers
on the IQ in Japan and Singapore. Both showed that the East Asians
obtained higher means than white Europeans in the United States
and Britain. These initial studies were criticised, but the present
book lists 60 studies of the IQs of indigenous East Asians all
of which confirm the original claim.
Hitherto
studies of race differences in intelligence have been largely conducted
and discussed in local contexts. In the United Sates they have
been largely concerned with the IQs of whites, blacks, Hispanics,
Asians and Native American Indians. In Australia they have been
concerned with the low IQ of the Aborigines, and in New Zealand
with the low IQ of the Maoris. These differences have typically
been explained by racism and discrimination of Europeans against
minorities the legacy of slavery, although a number of writers
have posited a significant genetic factor (Jensen, 1998; Rushton
and Jensen, 2005). Lynn’s book differs in taking
a global perspective and consists of a review more than 500 studies
published world wide from the beginning of the twentieth century
up to the present. He devotes a chapter to each of ten races, differentiated
by Cavalli-Sforza, Menozzi and Piazza (1994) into “genetic
clusters”, which he regards as a transparent euphemism for
races.
His conclusions are that the East Asians (Chinese,
Japanese and Koreans) have the highest mean IQ at 105. These are
followed by the Europeans (IQ 100). Some way below these are the
Inuit (Eskimos) (IQ 91), South East Asians (IQ 87), Native American
Indians (IQ 87), Pacific Islanders (IQ 85), South Asians and North
Africans (IQ 84). Well below these come the sub-Saharan Africans (IQ
67) followed by the Australian Aborigines (IQ 62). The least intelligent
races are the Bushmen of the Kalahari desert together with the
Pygmies of the Congo rain forests (IQ 54).
After the
ten chapters setting out the evidence for each of the ten races
there follows a chapter on the reliability and validity of the
measures. These show that the studies have high reliability in
the sense that different studies of racial IQs give closely similar
results. For instance, East Asians invariably obtain high IQs,
not only in their own native homelands but in Singapore, Malaysia,
Hawaii and North America. To establish the validity of the racial
IQs he shows that they have high correlations with performance
in the international studies of achievement in mathematics and
science. Racial IQs also have high correlations with national economic
development, providing a major contribution to the problem of why
the peoples of some nations are rich and others poor. He argues
further that the IQ differences between the races explain the differences
in achievement in making the Neolithic transition from hunter-gathering
to settled agriculture, the building of early civilizations, and
the development of mature civilizations during the last two thousand
years.
Lynn tackles the problem of the environmental
and genetic determinants of race differences in intelligence and
concludes that these contribute about equally to the phenotypic
differences. He argues that the consistency of racial IQs in many
different locations can only be explained by powerful genetic factors.
He works out the genetic contribution in most detail for the sub-Saharan
Africans. His argument is that sub-Saharan Africans in the United
States experience the same environment as whites, as regards determinants
of intelligence. He argues that they have as good nutrition as
whites, as shown by their having the same average height in studies
going back to World War 1, and they have approximately the same
education as whites. He presents evidence that blacks in the southern
states have very little white ancestry and have an IQ of about
80, and that proposes that this can be adopted as the genotypic
IQ of blacks, i.e. the IQ that blacks attain when they are reared
in the same environment as whites. The IQ of blacks in sub-Saharan
Africa is a good deal lower at 67. Hence, the adverse environment
in sub-Saharan Africa, which he regards as consisting principally
of poor nutrition and health, contributes about 13 IQ points to
the low IQ in sub-Saharan Africa. Lynn’s estimate is not
too different from that advanced in 1969 by Jensen to the effect
that about two thirds of the low IQ of blacks in the United States
is attributable to genetic factors, and the more recent estimate
of Rushton and Jensen (2005) that the figure is around 80 percent.
Lynn has (unsurprisingly for those familiar with his work) put
a bit more weight on the genetic factor.
The last three chapters are concerned with the book’s subtitle (An
Evolutionary Analysis) and discusses howrace differences in intelligence
have evolved. He begins by putting the problem in context by summarizing
Jerison’s
(1973) classic study showing that during the course of evolution
species have evolved greater intelligence in order to survive in
more cognitively demanding environments. For instance, in one of
the most dramatic of these developments, early mammals evolved
larger brains and greater intelligence to survive in the nocturnal
environment, for which they needed to evolve larger auditory and
olfactory analysing centres in the brain.
The same principle, Lynn argues, explains the evolution of race
differences in intelligence in humans. He elaborates the argument
he has advanced over the last fifteen years that the race differences
in intelligence have evolved as adaptations to colder environments
as early humans migrated out of Africa. In North Africa and South
Asia, and even more in Europe and Northeast Asia, these early humans
encountered the problems of having to survive during cold winters
when there were no plant foods and they had to hunt big game to
survive. They also had to solve the problems of keeping warm. These
required greater intelligence than was needed in tropical and semi-tropical
equatorial Africa where plant foods are plentiful throughout the
year. He shows that race differences in brain size and intelligence
are both closely associated with low winter temperatures in the
regions they inhabit. For instance, he gives a figure of 1282 cc
for the average brain size of sub-Saharan Africans, as compared
with 1367 cc for Europeans and 1416 cc for Orientals. His
analysis relating race differences in intelligence to exposure
to low winter temperatures has recently been independently corroborated
by Templer and Arikawa (2005).
From time to time Lynn notes anomalies in his theory that require
explanations. One of these is that the Europeans have made most
of the great intellectual advances and discoveries, while the East
Asians, despite having a higher IQ have made relatively few (as
extensively documented by Murray, 2003). Lynn proposes the explanation
for this may be that the East Asians are more conformist that Europeans
and this inhibits creative achievement. He also notes one or two
anomalies in his cold winter theory of race differences in intelligence.
The most striking of these is that the Inuit have been exposed
to the coldest winter temperatures and have evolved large brains,
the same average size as that of the East Asians. Yet their IQ
is only 91, and this is the IQ obtained by those who attend the
same schools as Europeans. To explain this anomaly he proposed
that two genetic processes must be assumed to explain the evolution
of race differences in intelligence. The first of these is that
differences in the frequencies of the alleles for high and low
intelligence have evolved between races such that the alleles for
high intelligence are more common in the races with the higher
IQs and less common in the races with the lower IQs. The early
humans that migrated out of Africa and spread throughout the world
would have carried all the alleles for high and low intelligence
with them, but those who colonized Asia and Europe were exposed
to the cognitively demanding problems of survival during cold winters.
Many of those carrying the alleles for low intelligence would have
been unable to survive during the cold winters and the less intelligent
individuals and tribes would have died out, leaving as survivors
the more intelligent. This process would have reduced and possibly
eliminated the alleles for low intelligence, leaving a higher proportion
of the alleles for high intelligence. The more severe the winter
temperatures, the greater the selection pressure for the elimination
of low IQ individuals carrying low IQ alleles. This process explains
the broad association between coldest winter temperatures and IQs
and brain size.
He now suggests that there must have been a second genetical
process that several new alleles for high intelligence must have
appeared as mutations in some races but did not appear in others, and once these
had appeared they were never transmitted to other races. These new mutant alleles
for high intelligence would have been most likely to appear in large populations
because a mutation is a chance genetic event and hence would have been more likely
to occur in races with large populations than in those with small.
The Inuit comprised only very small populations numbering today around 55,000,
so they would be unlikely have had mutations for higher intelligence that have
to be assumed in the East Asians and Europeans. Once a new mutant allele for
higher intelligence had appeared in the East Asians and Europeans it would have
conferred a selection advantage and would have spread throughout the group of
around 50 to 80 individuals in which people lived during the hunter-gatherer
stage of human evolution. It would then have spread fairly rapidly to adjacent
groups because hunter-peoples typically have alliances with neighboring groups
with which they exchange mating partners, and it is reasonable to assume that
this custom was present for many thousands of years during the evolution of the
races. These alliances of groups are known as demes, and
a new mutant allele for higher intelligence and which conferred
a selection advantage would have spread fairly rapidly through
a deme. From time to time matings would take place between demes
and by this means new mutant alleles for higher intelligence would
spread from one deme to another and eventually throughout an entire
race.
However, this would take some considerable time, and Lynn proposes
that in 25,000 years, consisting of approximately 1,000 generations,
an advantageous allele would be transmitted about 800 miles. Hence, an advantageous
allele occurring as a mutant in the region of, say, Beijing, 25,000 years ago
would not yet have spread outside China and would take another 50,000 years or
so to reach the Inuit peoples of far North East Asia and even longer to cross
the Bering Straits into Alaska. In addition, there are geographical
barriers of high mountains between the East Asians and the Inuit that would have
imposed a further impediment for the new alleles for higher intelligence being
transmitted from East Asia northwards. He extends this explanation to the low
IQs of the Australian Aborigines and Bushmen. These have only been small populations,
so the chance of mutations of high IQ alleles in them would have
been low.
To the arguments presented by Jensen (1998) for a substantial
genetic determination of the difference in intelligence between
blacks and whites in the United States, Lynn adds a more general
one. He advances the general principle of evolutionary biology
that wherever subspecies, strains or races have evolved in different
environments they invariably develop differences in all characteristics
for which there is genetic variation as a result of mutations occurring
in some subspecies and of adaptations to different environments,
and asserts that intelligence cannot be an exception. He concludes
witheringly that “The position of environmentalists
that over the course of some 100,000 years peoples separated by
geographical barriers in different parts of the world evolved into
ten different races with pronounced genetic differences in morphology,
blood groups and the incidence of genetic diseases, and yet have
identical genotypes for intelligence, is so improbable that those
who advance it must either be totally ignorant of the basic principles
of evolutionary biology or else have a political agenda to deny
the importance of race. Or both “. So much for the assertion
of the American Psychological Association’s
task force under the chairmanship of Ulrich Neisser set up to produce
a consensus statement on what is known about intelligence that
concluded that there is no persuasive evidence for genetic race
differences (Neisser et al., 1998). With the publication of Lynn’s
book it will never again be possible to make this assertion and
retain any credibility.
Over the years Lynn has made a number of important contributions
to the field of intelligence. He has written the standard works
on the dysgenic processes that have been taking place almost worldwide
for the last century and on how these could be addressed (Lynn,
1996, 2001). He has shown that the problem of why some nations
are rich and others poor is largely explained by the intelligence
of the populations (Lynn and Vanhanen, 2002). He has overturned
the century long consensus that there is no sex difference in intelligence
by showing that men have a higher average IQ than women by approximately
5 IQ points (Lynn and Irwing, 2004). But I would guess that the
present book documenting global race differences in intelligence
and analysing how these have evolved will come to be seen as his
crowning achievement. |
Cavalli-Sforza, L.L., Menozzi, P. and Piazza, A. (1994) The History
and Geography of Human Genes. Princeton, NJ: Princeton
University Press.
Jensen, A .R. (1998) The g Factor. Westport,CT: Praeger.
Jerison, H. (1973) Evolution
of the brain and intelligence.
New York: Academic Press.
Lynn, R. (1996) Dysgenics: Genetic Deterioration
in Modern Populations
Westport,CT: Praeger.
Lynn, R. (2001) Eugenics: A Reassessment. Westport, CT: Praeger.
Lynn, R. and Irwing, P. (2004) Sex differences on the Progressive Matrices:
a meta-analysis. Intelligence, 32, 481-498.
Lynn, R. and Vanhanen, T. (2002) IQ and the Wealth of Nations.
Westport, CT: Praeger.
Murray, C. (2003) Human Accomplishment. New York: Harper Collins.
Neisser, U.et al. (1996) Intelligence: knowns and unknowns. American
Psychologist, 51, 77-101.
Rushton, J. P. and Jensen, A. R. (2004) Thirty years of research on
race differences in cognitive ability. Psychology, Public Policy
and Law, 11, 235-294.
Templer, D.I. and Arikawa, H. (2005) Temperature, shin color, per capita
income and IQ: an international perspective. Intelligence, (to
appear)
Sets out evidence for race differences in intelligence worldwide. Concludes
that the average IQs of the races are Orientals 105; Europeans, 100;
South Asians, 90; Native American Indians, 90; Australian Aborigines,
90; sub-Saharan Africans, 75. |