Race and intelligence

Studies comparing races and ethnic groups with IQ among U.S. test subjects show differences in average test scores, though the distributions overlap, as seen in this graph based on Template:AYref (see body text for further references). The causes and meaning of the different average scores for these groups are debated.

Race and intelligence is a controversial interdisciplinary field studying the nature, origins, and practical consequences of possible racial and ethnic group differences in intelligence. This research relies on several debated assumptions, including:

• self-identified race is a useful categorization for social science research and can produce scientifically meaningful conclusions.
• intelligence can be measured (see IQ) and/or is dominated by a unitary general cognitive ability.

While the distributions of IQ scores of different racial-ethnic groups overlap considerably, groups differ in where their members cluster along the IQ scale. ^[1] Similar clustering occurs with related variables, such as school achievement, reaction time, and brain size. ^[2] In the U.S., most variation in IQ occurs within individual families, not between races. Nevertheless, differences of average IQs among groups have been examined extensively.

Many hypotheses have been proposed to explain racial-ethnic group differences in IQ. Certain environmental factors, such as childhood nutrition, are known to modulate IQ, and other influences have been hypothesized, including education level, richness of the early home environment, and other social, cultural or economic factors. The primary focus of the scientific debate is whether group IQ differences also reflect a genetic component. Hypothetically, a genetic contribution to intelligence could include genes linked to neuron structure or function, brain size, or brain metabolism, that vary with ancestral background.

The findings of this field are often thought to conflict with fundamental social philosophies, and have thus engendered a large controversy. Public debates in this area often contain misconceptions. Critics examine the fairness and validity of cognitive testing and racial categorization, as well as the reliability of the studies and the motives of the authors, on both sides. Critics often fear the misuse of the research, question its utility, feel that comparing the intelligence of racial groups is itself unethical, or fear sociopolitical ramifications, whether justified or unjustified. For instance, the disparity in average IQ among racial groups is sometimes mistaken for the idea that all members of one race are more intelligent than all members of another.

Background information

Racial distinctions are most often made on the basis of skin color, facial features, ancestry, and national origin. Some scientists argue that common racial classifications are not meaningful, often on the basis of research indicating that more genetic variation exists within such races than between them. To define terms, racial labels most commonly used in the United States relate to genetic ancestry (Tang et al., 2005). People labeled Blacks have most of their ancestors from sub-Saharan Africa, Whites from Europe (and sometimes the Middle East and North Africa), and East Asians from countries on the western side of the Pacific Rim. Hispanics, more often called an ethnic group rather than a race, form a genetically diverse group that includes many recent U.S. immigrants of mixed ancestry. The political, social and cultural structure of the United States is still explicitly conscious of race. Legal equality of Whites and Blacks was not fully actualized until the 20th century. The national and state governments of the United States employ racial categorization in the census, law enforcement, and innumerable other ways. Many races have political organizations to represent their interests. Racial discrimination is illegal in many areas of public and private life, including employment. See the articles Race and Race (U.S. Census) for further discussion.

Cognitive ability (i.e., intelligence) is most commonly measured using IQ tests. These tests are often geared to be good measures of the psychometric variable g, and other tests that measure g (e.g., the Armed Forces Qualifying Test) also serve as measures of cognitive ability. All such tests are often called "intelligence tests," though the term "intelligence" is itself controversial. It is clear, however, that performance in these tests accurately predicts performance in similar life tasks (typical college courses, for example). In this article, "IQ test" denotes any test of cognitive ability, and "IQ" is used as a shorthand for scores on tests of cognitive ability. Some critics question the validity of all IQ testing or claim that there are aspects of "intelligence" not reflected in IQ tests. Criticisms of the validity of IQ testing focus primarily on questions of "test bias", which has many related meanings. See the articles Intelligence, IQ, and general intelligence factor for further discussion of the validity of these tests.

The contemporary scholarly debate about race and intelligence involves both the relatively uncontroversial experimental results that indicate that average IQ test scores vary among racial groups, and the relatively more controversial interpretations of these IQ differences. In general, contemporary interpretations of the "IQ gap" can be divided into three broad categories:

1. "culture-only" or "environment-only" interpretations that posit only non-genetic causes (e.g., socioeconomic inequality or minority group membership) that differentially affect racial groups; and
2. "partly genetic" interpretations that posit an IQ gap between racial groups caused by approximately the same matrix of genetic and environmental forces that cause IQ differences among individuals of the same race.
3. "insufficient data": no meaningful interpretation can be made based on available evidence.

History

Sir Francis Galton wrote on eugenics and psychometrics in the 19th century.

The scientific debate on the contribution of nature versus nurture to individual and group differences in intelligence can be traced to at least the mid-19th century^[3]. The writings of Sir Francis Galton, elaborating on the work of his cousin Charles Darwin, spurred interest in the study of mental abilities, particularly as they relate to heredity and eugenics.

The fact that there are differences in the brain sizes and brain structures of different racial and ethnic groups was well known and widely studied during the 19th century and early 20th century^[4].

Average ethnic and racial group differences in IQ were first found due to the widespread use of standardized mental tests during World War I.

Beginning in the 1930s, hereditarianism — the belief that genetics contribute to differences in intelligence among humans — began to fall out of favor, in part due to the advocacy of Franz Boas, who in his 1938 edition of The Mind of Primitive Man wrote

...there is nothing at all that could be interpreted as suggesting any material difference in the mental capacity of the bulk of the Negro population as compared with the bulk of the White population.

Anthropologist Franz Boas was a prominent 20th century critic of claims that intelligence was measurable and differed among races.

The hereditarian position was greatly weakened by Boas' finding that cranial vault size had increased significantly in the U.S. from one generation to the next, because racial differences in such characteristics had been among the strongest arguments for a genetic role.

Eugenics was later adopted by the Nazi party as a justification for the systematic elimination of "parasitic" races such as Jews and Gypsies. (Note that the Ashkenazi Jewish population has significantly higher average IQ scores than other Whites.)

Due to the association of hereditarianism with Nazi Germany, after the conclusion of World War II until the 1994 publication of The Bell Curve, it became largely taboo to suggest that there were racial or ethnic differences in measures of intellectual or academic ability and even more taboo to suggest that they might involve a genetic component.^[5]

In 1961, the psychologist Henry Garrett coined the term equalitarian dogma to describe the then politically fashionable view that there were no race differences in intelligence, or if there were, they were purely the result of environmental factors. Those who questioned these views often put their careers at risk.^[6].

The contemporary scholarly debate on race and intelligence may be traced to Arthur Jensen's 1969 publication in the Harvard Educational Review of "How Much Can We Boost IQ and School Achievement?" In this paper Jensen concluded that:

(a) IQ tests measure socially relevant general ability; (b) individual differences in IQ have a high heritability, at least for the White populations of the United States and Europe; (c) compensatory educational programs have proved generally ineffective in raising the IQs or school achievement of individuals or groups; (d) because social mobility is linked to ability, social class differences in IQ probably have an appreciable genetic component; and tentatively, but most controversially, (e) the mean Black-White group difference in IQ probably has some genetic component (from Rushton & Jensen, 2005).

Reports on Jensen's article appeared in Time, Newsweek, Life, U.S. News & World Report, and The New York Times Magazine. Press attention returned to the issue of race and intelligence in 1994 with the publication of The Bell Curve (Herrnstein & Murray, 1994), which included two chapters on the subject of racial difference in intelligence and related life outcomes. In response to The Bell Curve, Stephen Gould updated The Mismeasure of Man, criticizing many aspects of IQ research.

In 2005, the scholarly debate continues on the question of "whether the cause of group differences in average IQ is purely social, economic, and cultural or whether genetic factors are also involved" (Rushton & Jensen, 2005).

Bias and the Pioneer Fund

The scientific community accepts that research can be biased due to various conflicts of interest. Therefore, many scientific journals, especially in controversial areas, require that the researcher should let the readers know any potential conflicts of interests that can have affected the research, like financial ties or the source of the funding for the research [7]. Many critics of the research claiming genetic differences in IQ have criticized the source of much of the funding for this research, the Pioneer Fund (Template:AYref [8]).

The Southern Poverty Law Center (SPLC), an anti-racism organization, lists the Pioneer Fund as a "hate group" due to its funding of many allegedly racist or fascist organizations and individuals [9]. However, the SPLC itself has been accused of exaggerating the threat of racism in order to increase fund-raising revenue and of wrongfully applying the term "hate group" to legitimate organizations. A Pulitzer Prize winning investigative report of the SPLC found evidence of racial discrimination and finanical impropriety.

Many of the IQ researchers supporting genetic differences in intelligence between races, like the IQ researcher and current head of the fund J. Philippe Rushton, have received millions of dollars in monetary grants from the Pioneer Fund. Defenders argue that established standards of evaluating scientific research required that the grantees supported by the Pioneer Fund be judged only on the scientific merits of their research.

Scholar William H. Tucker has questioned the whole field due to this funding. "My commitment to the right to unfettered research is not diminished one iota by my contention, described in detail elsewhere, that research into racial differences in intelligence has provided no results of any scientific value and that it has been used primarily, if not exclusively, to legitimate racist ideology" [10][11].

Systematic misrepresentations?

Researchers on both sides of the debate have been accused by other researchers variously of bias or of systematically misrepresenting the available data, especially when trying to associate the results with various other claimed differences in personality and physical characteristics. As an example of criticism of the hereditarian side, when some of Rushton's claimed supporting references were examined, they were found to include a nonscientific semipornographic book and an article in Penthouse Forum.^[12] Some recent claims by the same researchers have also been criticized; see Brain size. As an example of criticism of the non-hereditarian side, Stephen Jay Gould, one of the leading critics of race and intelligence research, has been accused of "scholarly malfeasance," (Template:AYref), tainting his research with a Marxist bias (Template:AYref), and presenting misleading statistics.^[13]

Public controversy

Main article: Race and intelligence (public controversy)

Average test score gaps among races

Main article: Race and intelligence (Average gaps among races)

File:IQ-4races-rotate-highres.png

Cumulative IQ gaps by race or ethnicity based on 1981 U.S. distributions. According to these findings, WAIS IQs for Whites (mean = 101.4, SD = 14.7) were higher than Blacks (mean = 86.9, SD = 13.0); distributions for Hispanics (mean = 91) and Asians (mean = 106) are less precise because of overlap and small sample size. Critics claim results like these are not grounded in scientifically derived constructs, but rather in folk beliefs about them. Based on Template:AYref, p. 330.

The modern controversy surrounding intelligence and race focuses on the results of IQ studies conducted during the second half of the 20th century, mainly in the United States and some other industrialized nations. In almost every testing situation where tests were administered and evaluated correctly, a difference of approximately one standard deviation was observed in the US between the mean IQ score of Blacks and Whites. Attempted world-wide compilations of average IQ by race generally place Ashkenazi Jews at the top, followed by East Asians, Whites, other Asians, Arabs, Blacks and Australian Aborigines. See IQ and the Wealth of Nations for an attempted compilation of average IQ for different nations and a discussion of associated measurement problems. The IQ scores vary greatly among different nations for the same group. Blacks in Africa score much lower than Blacks in the US. Some reports indicate that the Black–White gap is smaller in the UK than in the U.S.^[14] Many studies also show large differences in IQ between different groups of Whites. For example, in Northern Ireland the IQ gap between Protestants and Catholics is as large as that between Blacks and Whites in the US. In Israel, large gaps in test scores and achievement separate Ashkenazi Jews from other groups such as the Sephardi Template:AYref.

IQ has a low to moderate correlation with various measures of brain size and performance on elementary tests of response time (Template:AYref. Studies have shown similar racial differences in these variables. Cranial vault size and shape have changed greatly during the last 150 years in the US. These changes must occur by early childhood because of the early development of the vault. The explanation for these changes may be related to the Flynn effect.^[15]

Gaps are seen in other tests of cognitive ability or aptitude, including university admission exams such as the SAT and GRE as well as employment tests for corporate settings and the military (Template:AYref). Measures of school achievement correlate fairly well with IQ, especially in younger children. In the United States, achievement tests find that by 12th grade Black students are performing on average only as well as White and Asian students in 8th grade; Hispanic students do only slightly better than Blacks. Whether the gaps are narrowing or not is debated.

Culture-only or partially genetic explanation?

Main article: Race and intelligence (Culture-only or partially-genetic explanation)

The consensus among intelligence researchers is that IQ differences among individuals of the same race reflect (1) real, (2) functionally/socially significant, and (3) substantially genetic differences in the general intelligence factor. A consensus also exists for the view that average IQ differences among races reflect (1) real and (2) significant differences in the same g factor.^[16] However, it is a matter of debate whether IQ differences among races in the U.S. are (3a) entirely environmental or (3b) partly genetic. Several published consensus statements agree that the large difference between the average IQ scores of Blacks and Whites in the U.S. cannot be attributed to biases in test construction, nor can they be explained just by simple differences in socio-economic status. It should be noted that most research has been done in the US and a few other developed nations. That research cannot directly be generalized to the world as a whole. Blacks in the US do not constitute a random sample of the original African population, and environmental conditions differ among nations. IQ tests done in developing countries are likely to have been affected by conditions associated with poverty that are common in the developing world, such as nutritional deficiencies and the impact of diseases (e.g., HIV, anemia or chronic parasites that may affect IQ test scores).

Regarding the IQ gaps in the U.S., it has also been suggested that Black culture disfavors academic achievement and fosters an environment that is damaging to IQ (Template:AYref). Likewise, it is argued that a persistence of racism reinforces this negative effect. John Ogbu (Template:AYref, Template:AYref) has developed a hypothesis that the condition of being a "caste-like minority" affects motivation and achievement, depressing IQ. Many anthropologists have argued that intelligence is a cultural category; some cultures emphasize speed and competition more than others, for example. Even proponents of the view that the IQ gap is caused partly by genetic differences recognize that non-genetic factors are likely to be involved. Non-genetic biological factors that affect IQ have been proposed. Increased rates of low birth weight babies and lower rates of breastfeeding in Blacks as compared to Whites are some factors of many that have been proposed to affect the IQ gap. Many studies that directly test for heritability find results that do not support the genetic hypothesis. They include studies on IQ and skin color, self-reported European ancestry, blood groups, children in postwar Germany born to black and white American soldiers, and mixed-race children born to either a Black or a White mother. Many intervention and adaption studies also find results that do not support the genetic hypothesis (Template:AYref). The Flynn effect is often cited as evidence that average IQ scores have changed greatly and rapidly, for reasons poorly understood, noting that average IQ in the US may have been below 75 before the start of this effect. Some argue that the evidence persuasively indicates that the IQ gap among races could change in the future or is even now changing. On the plausible supposition that the effect started earlier for Whites, since their social and economical conditions began to improve earlier than did those of Blacks, they see even more promise in this hypothesis.

Arthur Jensen and others have concluded that the IQ gap is partly genetic. They argue that while plausible environmental explanation for the lower mean IQ in Blacks in the U.S. can be offered in many cases, these explanations are less capable of explaining the higher average IQ of East Asians than Whites. Using Lakatos’s classification of research programmes they claim that the culture-only hypothesis is not “progressive” but “degenerating” (Template:AYref). To support these claims, they most often cite: (1) worldwide Black–White–East Asian differences in IQ, reaction time, and brain size; (2) correlation between the extent to which IQ subtests measure g, the magnitude of Black–White–East Asian average IQ differences on those subtests (see Spearman's hypothesis), and measures of those subtests' heritability; and (3) the rising heritability of IQ with age (within races) and the disappearance by adulthood of shared environmental effects on IQ (e.g., family income, education, and home environment). Other evidence, such as transracial adoption, racial admixture studies, "life-history" traits, and evolutionary explanations are also debated. Critics of this view, such as Robert Sternberg, have many counter arguments, and suggest that a definite answer may not be possible until intelligence is directly linked to specific genes.

Significance of group IQ differences

See also: Practical importance of IQ

There is substantial overlap in the distribution of IQ scores among individuals of each race. Jensen (1998, p. 357) estimates that in a random sample of equal numbers of US Blacks and Whites, most of variance in IQ would be unrelated to race or social class. The average IQ difference between two randomly paired people from the U.S. population, one Black and one White, is approximately 20 points. However, by the same method of calculation, the average difference between two random people is approximately 17 points, and the average difference between two siblings is 12 points.

The appearance of a large practical importance for intelligence makes some scholars claim that the source and meaning of the IQ gap is a pressing social concern. The IQ gap is reflected by gaps in the academic, economic, and social factors correlated with IQ (Gordon 1997; Gottfredson 1997). However, some dispute the general importance of the role of IQ for real-world outcomes, especially for differences in accumulated wealth and general economic inequality in a nation. See the "Practical importance of IQ" link above.

Two statistical effects interact to exacerbate group IQ differences. First, there seem to be minimum statistical thresholds of IQ for many socially valued outcomes (e.g., high school graduation and college admission). Second, because of the shape of the normal distribution, only about 16% of the population is at least one standard deviation above the mean. Thus, although the IQ distributions for Blacks and Whites are largely overlapping, different IQ thresholds can have a significant impact on the proportion of Blacks and Whites above and below a particular cut-off.

Approximate IQ Distributions & Significance in the United States

IQ range	Whites	Blacks	Black:White ratio	Training prospects	High school dropout	Lives in poverty
<75	3.6%	18.0%	~5:1	simple, supervised work; eligible for government assistance	55%	30%
<90	21.9%	59.4%	~2:1	very explicit hands on training; IQ >80 for military training; no government assistance	35%	16%
>100	53.8%	15.7%	~1:3	written material plus experience	6%	6%
>110	27.9%	3.8%	~1:7	college format	0.4%	3%
>125	5.4%	0.2%	~1:32	independent, self-teaching	0%	2%
Based on Wechsler Adult Intelligence Scale IQs for Whites (mean = 101.4, SD = 14.7) and for Blacks (mean = 86.9, SD = 13.0) from (Reynolds, Chastain, Kaufman, & McLean, 1987, p. 330). Significance data is from Herrnstein & Murray (1994). Note that correlation is not causation. For example poverty can be both a cause and consequence of low IQ.

Small differences in IQ, while relatively unimportant at the level of an individual, would theoretically have large effects at a population level. Herrnstein and Murray (1994) calculate that a 3-point drop in average IQ would have little effect on factors like marriage, divorce, or unemployment. However, the drop from IQ 100 to 97 would increase poverty rates by 11 percent and the proportion of children living in poverty by 13 percent. All else being equal, similar rises would occur in rates of children born to single mothers, men in jail, high school drop-out, and men prevented from working due to health-related problems. In contrast, if average IQ were to increase 3-points to 103, poverty rates would fall 25 percent, children living in poverty would fall 20 percent, and high school drop-out rates would fall 28 percent.

Percentages of Blacks and Whites (Statistically Matched for IQ) in Educational and Social Outcomes

Condition (matching IQ)	Blacks	Whites
High school graduation (103)	91	89
College graduation (114)	68	50
High-level occupation (117)	26	10
Living in poverty (100)	14	6
Unemployed for 1 month or more (100)	15	11
Married by age 30 (100)	58	79
Unwed mother with children (100)	51	10
Has ever been on welfare (100)	30	12
Mothers in poverty receiving welfare (100)	74	56
Having a low birth-weight baby (100)	6	3
Average annual wage (100)	$25,001	$25,546
from Herrnstein & Murray (1994), Chapter 14.

Studies from The Bell Curve and elsewhere indicate that controlling for IQ narrows, eliminates, or even reverses the Black-White gap in social and economic factors associated with IQ. After controlling for IQ, the probability of having a college degree or working in a high-IQ occupation is higher for Blacks than Whites. Controlling for IQ shrinks the income gap from thousands to a few hundred dollars. Controlling for IQ cuts differential poverty by about three-quarters and unemployment differences by half. However, controlling for IQ has little effect on differential marriage rates. For many other factors, controlling for IQ eliminates the differences between Whites and Hispanics, but the Black-White gap remains (albeit smaller).

Another study found that wealth, race and schooling are important to the inheritance of economic status, but IQ is not a major contributor and the genetic transmission of IQ is even less important.^[17]

Whites are not a homogeneous group regarding real-world outcomes. For example, in the U.S. 33.6% of persons with self-reported Scottish ancestry has completed college, while only 16.7% of persons with self-reported French-Canadian ancestry have done so.^[18]

Differences in intelligence have been used to explain differences in economic growth between nations. One example is IQ and the Wealth of Nations. The book, which has not been peer-reviewed, is sharply criticized in the peer-reviewed paper The Impact of National IQ on Income and Growth.^[19] It has been argued that East Asian nations underachieve compared to IQ scores. One suggested explanation is that verbal IQ is more important than spatial IQ.^[20] The book Guns, Germs and Steel instead argues that historical differences in economic and technological development for different areas can be explained by differences in geography, which affects factors like population density and spread of new technology, noting for instance that current IQ scores cannot explain why the world's first civilizations appeared along the river plains in the Middle East.

The book World on Fire notes the existence in many nations of successful minorities that have created and control a disproportionate share of the economy. Examples include Chinese in Southeast Asia; Whites, Indians, Lebanese and Ibo in Africa; Whites in Latin America; and Jews in Russia. These minorities are often resented and sometimes persecuted by the less successful majority.

In the United States, Jews, Japanese, and Chinese earn incomes 1.72, 1.32, and 1.12 times the American average, respectively (Sowell, 1981, p. 5). Jews and East Asians have higher rates of college attendance, greater educational attainment, and are many times overrepresented in the Ivy League and many of the United States' most prestigious schools (Sowell, pp. 7, 93)^[21], even though affirmative action discriminates against East Asians in the admissions process (relative to Whites as well as to other minorities). In various Southeast Asian nations, Chinese control a majority of the wealth despite being a minority of the population and are resented by the majority, and in some cases are the target of violence (Sowell, pp. 133-134; Purdey, 2002).

Achievement in science, a high-complexity occupation in which practitioners tend to have IQs well above average, also appears consistent with some group IQ disparity. Only 0.25% of the world population is Jewish, but Jews make up 20–30% of all Nobel prize winners in physics, chemistry, and medicine.^[22] A significant decline in the number of Nobel prizes awarded to Europeans, and a corresponding increase in the number of prizes awarded to US citizens, occurred at the same time as Nazi persecutions of Jews during the 1930s and the Holocaust during the 1940s.^[23]

Policy implications

See also: Intelligence and public policy

The public policy implications of IQ and race research are possibly the greatest source of controversy surrounding this issue. For example, the conservative policy recommendations of Herrnstein and Murray in The Bell Curve were denounced by many. Indeed, even proponents of a partly genetic interpretation of the IQ gap such as Rushton and Jensen (2005) and Gottfredson (2005b) argue that their interpretation does not in itself demand any particular policy response: while a conservative/libertarian commentator may feel the results justify reductions in affirmative action, a liberal commentator may argue from a Rawlsian point of view (that genetic advantages are undeserved and unjust) for substantial affirmative action (Gottfredson, 2005b). According to the "Mainstream Science on Intelligence" statement published in the Wall Street Journal in 1994:

The research findings neither dictate nor preclude any particular social policy, because they can never determine our goals. They can, however, help us estimate the likely success and side-effects of pursuing those goals via different means.^[24]

While not specifically race-related, policies focused on geographical regions or nations may have disproportionate influences on certain racial groups and on cognitive development. Differences in healthcare, nutrition, regulation of environmental toxins, and geographic distribution of diseases and control strategies between the developing world and developed nations have all been subjects of policies or policy recommendations (see health and nutrition policies relating to intelligence).

Finally, genetic engineering may one day be able to directly change any genetic determinants found to influence intelligence, racial traits (like skin color) or both. This change may make the genetic component of intelligence and/or racial characteristics a matter of voluntary parental (or enforced governmental) decision. In principle, such advancements would make the current concept and discussion of race and intelligence obsolete.

Further reading

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Notes

1. ^ Template:AYref ; Roth et al., 2001; Rushton, 1995; Shuey, 1958; Herrnstein & Murray, 1994; Lynn, 1991a. For samples of individual studies showing similar results, see the National Collaborative Perinatal Project, reported by Template:AYref; also Lynn, 1997a, 1997b, 1982, 1987, 1991; Lynn, Chan, & Eysenck, 1991; Lynn & Hampson, 1986a, 1986b; Lynn, Hampson, & Bingham, 1987, Lynn, Hampson, & Iwasaki, 1987; Lynn, Hampson, & Lee, 1988; Lynn & Holmshaw, 1990; Lynn, Pagliari & Chan, 1988; Lynn & Shigehasa, 1991; Montie & Fagan, 1988; Scarr & Weinberg, 1987; Rushton, 1997; Rushton & Jensen, 2003; Rushton, Skuy, & Fridjhon, 2003; Notcutt, 1950; Osborne, 1978; Garrett, 1964, 1967; Jensen, 1985, 1993; Jensen & Reynolds, 1982; Template:AYref; Template:AYref
2. ^ Template:AYref; Template:AYref; Template:AYref; Template:AYref
3. ^ Template:AYref; Template:AYref
4. ^ Template:AYref
5. ^ Template:AYref, Template:AYref pp. 45–54.
6. ^ Template:AYref pp. 67–69.
7. ^ , Template:AYref
8. ^ American Anthropological Association. Statement on "Race" and Intelligence. Adopted December 1994.
9. ^ Template:AYref Of the 100 respondents, 52% signed, 7% indicated that elements of the statement do not represent the mainstream, and 11% did not know enough to say. An additional 14% declined to sign despite generally agreeing with the content, with 8% fearing the personal and professional consequences of signing, and 6% disagreeing with the mode of presentation. Another 4% disagreed with the concept of general intelligence itself, regarding it as “not a useful concept." 12% gave no explanation or did not want to sign "at this time." Thirty-one additional invitees did not respond before the deadline.
10. ^ Template:AYref
11. ^ Template:AYref
12. ^ Joseph L Graves, "What a tangled web he weaves: Race, reproductive strategies and Rushton's life history theory," Anthropological Theory 2, no. 2 (2002): 131–54; Leonard Lieberman, "How 'Caucasoids' got such big crania and why they shrank. From Morton to Rushton.," Current Anthropology 42, no. 1 (February 2001): 69–95; Zack Cernovsky, "On the similarities of American blacks and whites: A reply to J.P. Rushton," Journal of Black Studies 25 (1995): 672.
13. ^ J. Philippe Rushton, "Race, Intelligence and the Brain: The Errors and Omissions of the 'Revised' Edition of S.J. Gould's The Measure of Man," Journal of Individual Differences 23, no. 1 (1997): 169–80.
14. ^ Phil Gasper, "A scientist of the people," SocialistWorker.org, June 7, 2002.
15. ^ Goosed-Up Graphics: A generalization of the Lie Factor, graphs from Full House: The Spread of Excellence from Plato to Darwin, by Stephen Jay Gould (Three Rivers, MI: Three Rivers Press, 1997): 109, fig. 16.
16. ^ Template:AYref, Template:AYref, Template:AYref
17. ^ "Racial Scientist Rushton Takes Over Pioneer Fund," Bethune Institute for Anti-Fascist Studies, January 2003.
18. ^ Linda S. Gottfredson, "The General Intelligence Factor," Scientific American.
19. ^ "IQ comments". Gene Expression. September 23. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
20. ^ Clarence C. Gravlee, H. Russell Bernard, and William R. Leonard, "Heredity, Environment, and Cranial Form: A Reanalysis of Boas’s Immigrant Data," American Anthropologist 105, no. 1 (2003); Gravlee, Bernard, and Leonard, "Boas’s Changes in Bodily Form: The Immigrant Study, Cranial Plasticity, and Boas’s Physical Anthropology," American Anthropologist 105, no. 2 (June 2003); R.L. Jantz and Lee Meadows Jantz, "Secular change in craniofacial morphology," American Journal of Human Biology 12, no. 3 (April 1999): 327–38; R.L. Jantz, "Cranial change in Americans: 1850–1975," Journal of Forensic Sciences 46, no. 4 (July 2001): 784–87.
21. ^ Gottfredson (2005b); Template:AYref; Template:AYref; Template:AYref
22. ^ Samuel Bowles and Herbert Gintis, "The Inheritance of Inequality," Journal of Economic Perspectives 16, no. 3 (Summer 2002). Note that race, schooling and IQ are all correlated, so considering them as separate factors lessens the apparent effect of IQ.
23. ^ Myth: Some ethnic groups have genetically inferior IQ's, U.S. Census data reported by Andrew Hacker; "Caste, Crime and Precocity," in The Bell Curve Wars, by Steven Fraser ed. (New York: HarperCollins, 1995), 105.
24. ^ Thomas Volken, "The Impact of National IQ on Income and Growth."
25. ^ "Smart Fraction Theory II: Why Asians Lag," La Griffe du Lion 6, no. 2 (May 2004).
26. ^ Gerhard Falk, "American Jews"
27. ^ Jewish Nobel Prize Winners, JINFO.ORG.
28. ^ Wolfgang Jank, Bruce L. Golden, and Paul F. Zantek, "Old World vs. New World: Evolution of Nobel Prize Shares," University of Maryland (December 2004).
29. ^ See note 5 above.

See also

• Brain to body mass ratio
• Craniometry
• Neuroscience and intelligence
• Race and crime
• Sex and intelligence
• Scientific racism

References

Main article: Race and intelligence (References)

External links

Consensus Statements

• Statement on "Race" and Intelligence. American Anthropological Association. Adopted December 1994.
• The Wall Street Journal: Mainstream Science on IntelligencePDF
• APA Task Force Examines the Knowns and Unknowns of Intelligence

Review Papers

• June 2005 issue of Psychology, Public Policy, and Law, Vol. 11, No. 2.
  • Thirty Years of Research on Race Differences in Cognitive Ability J. Philippe Rushton & Arthur R. Jensen
  • There Are No Public-Policy Implications Robert J. Sternberg
  • What if the Heriditarian Hypothesis is True? Linda S. Gottfredson
  • Heredity, Environment, and Race Differences in IQ Richard E. Nisbett
  • The Cultural Malleability of Intelligence and Its Impact on the Racial/Ethnic Hierarchy Lisa Suzuki & Joshua Aronson
  • Wanted: More Race Realism, Less Moralistic Fallacy J. Philippe Rushton & Arthur R. Jensen
• Race, Genetics and IQ Richard E. Nisbett (PDF)

Others

• The Skeptic's Dictionary entry on IQ and race
• Poverty and Brain Development in Early Childhood 1999 report
• The Early Catastrophe: The 30 Million Word Gap by Age, American Educator, Spring 2003
• The Black-White Test Score Gap (1998) online (page-image) version of ISBN 0815746091
• Miscellaneous articles by Richard Lynn et al.
• Crippled by Their Culture - Race doesn't hold back America's black rednecks. Nor does racism by Thomas Sowell
• Cultural Bias in Intelligence Testing
• Cultural Bias in IQ Testing
• Are IQ Tests Biased?
• Psychological Testing (Powerpoint)
• Culturally Inane
• Scholars Provide an Overview of Explanations for Black-White Test Score Gap
• School Readiness: Closing Racial and Ethnic Gaps
• Variation in IQ, Brain Capacity, Size and Density by Race

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