The First World War catapulted the use of mental testing within the United States of America by testing mental ability to conscripts to the war. The data helped to provide critical assumption of lower I.Q. scored by Blacks compared to whites (Kamin, 1974).
Jenson (1969) argued that IQ tests confirm the racial and class difference and the assumption that such differences were highly heritable. Jensen proposed that IQ has a heritability of 0.8 or 80% within the population groups of American whites and blacks. On his tests, the average difference between American whites and blacks was 15 points and the difference of 15-30 points in socio-economic classes. He insisted that the discrepancy could not plausibly be a product of environment though this cites much criticism. To illustrate, some States have banned I.Q. testing, such as New York, this provides proof that there is some doubt on their validity. In addition, most of his estimates of heritability were based on the work done by the late Sir Cyril Burt on identical twins, reared apart. These studies were shown to be fraudulent as he tried to fit his data to his own ideals. Kamin (1974) found that the data he produced was full of errors and criticised his methodology.
Jenson (1987) claimed that data from between family or within family that general intelligence remains static. He argued that IQ tests with heavy g-loading can be excluded from environmental effects and such tests also show greatest differences within black and white populations. However, Flynn (1987) disregarded this, he found a large IQ generation gap between 1950 and 1980 using the same high g-loading. He suggested such a gap is due to environmental influences. Many German women became pregnant after World War II to both Black and White soldiers. Eyferth (1961) found no differences between the IQ of the two groups and in addition, found no benefit of having a White father compared to having a Black father. Flynn (1987) stated that IQ tests do not measure intelligence but correlate weakly with an underlying link to intelligence. The Flynn effect argued that IQ gains were culturally based.
Similarly Eysenck favours the genetic approach and agreed that 80% of variability within an individuals intelligence is grounded by genetics. He draws upon Twin studies and sibling studies. However, one such study conducted by Shields (1962) used predominately women, the age range was quite large and it was found that they hadn’t been separated until around 8years of age. Furthermore a study by Schiff, Dyme, Durmaret, Stewart, Tomkiewics and Fiengold (1978) found that the I.Q.s of 32 French Children from a lower class background when adopted into a higher status family were higher, 111 compared to 95, compared to 20 siblings. This backs up claims of an environmental effect.
Human Genome Project 2001
Lynn and Vanhanan (2002) would have us believe that poor nations will remain poor. They suggest this is due to hereditary features and therefore the economic differences between rich and poor nations will remain. But surely greed of rich nations, inadequate resources and civil war are all proof of environmental outcomes. IQ rates in such a nation is of little consequence when it is survival rates that matter.
Lynn (1977) outrageously assumes that the categories, Mongoloid and Causacoid high intelligence when compared to Negroid is due to their survival in temperate as well as cold climates.
DeVries and Sameroff (1984) found variations between three African tribes, which casts doubt on the limited sampling from British and American studies of Blacks. This highlights the shortcomings of data used in intelligence studies in which, Britian and America have diverse populations, indicating mixed genes and there appears to be great difficulty in generalising this amongst groups.
Rushton (1985) held a hereditary perspective on intellectual differences and he split race into three categories, Mongoloid, Causacoid and Negroid. However, Howe (1997) argued that he failed to consider the environmental influences such as social and economic factors. To demonstrate this using height, it can be said that genetic features are only part in variability, whether it can thrive or not depends largely on a healthy environment (Alland, 1996).
The Bell Curve by Herrnstein and Murray (1994) detailed data from the National longitudinal Study of Youth using 12,000 youths. They studied the relationship between low intelligence and anti-social behaviour, between low African-Americans compared to whites and Asians and genetic factors within intelligence. Controversially, they stated that white IQ was lower than that of Asian IQ, whilst Black IQ was low compared to white. However, their study used a primarily white sample and by doing so removed the racial differences element. They found that low intelligence is related to poverty, health, welfare dependency and single motherhood. This revealed the social economic nature effects of low intelligence within a given country.
Mackintosh (1998) makes a point in that intelligence is so obscure that it is impossible to measure. Another statement suggests that most population samples from Britian or America or Africa differ in many ways from values and beliefs and therefore makes comparison between groups even more difficult. Sternberg (1985) claims that an individuals’ social and cultural features tend to be integrated within intelligence. Additionally, he acknowledges that IQ tests are useful in Educational contexts but only within the societies they were primarily made for.
Zuckerman (1990) argues that genetic research be criticised not because of the racist connotations but because there is no real justification in the systematic study of differences of innate intelligence within different ethnic groups. Furthermore he claims that more emphasis should be made on biological and social aspects of individual differences relating to personality and intelligence within peoples of the world. Additionally, Pasamanick and Knobloch (1966) argue that poverty can cause cultural and physical deprivation and that this may have a causal link in reduced intellect within individual. They have found that environment factors such as social class, health and education do play apart in aspects of intelligence.
The genetic promonent is problematic because of the irrelevance of I.Q. tests to determine racial differences in intelligence. I.Q. tests only indicate the ability, conditioned by culture (Flynn 1987).
References
Alland, 1996).
DeVries and Sameroff (1984)
Evans and Waites 1981
Eyferth (1961)
Eysenck
Flynn. J. R. (1987). Massive IQ gains in 14 nations: What IQ tests really measure. Psychological Bulletin, 101, 171-191.
Flynn, J. R. (1999). Searching for justice: The discovery of IQ gains over time. American Psychologist, 54, 5-20.
Galton (1884
Gould 1997)
Herrnstein, R. J. and Murray, C., (1994). The Bell Curve. New York: The Free Press.
Howe
Jenson (1969)
Kamin, L.J. (1974). The science and politics of IQ. Potomac, MD: Lawrence Erlbaum Associates.
Lynn. R. and Vanhanan. T. (2002). IQ And The Wealth Of Nations. Praeger
Pasamanick and Knobloch (1966
Rose 1984;
Rushton (1985)
Schiff, Dyme, Durmaret, Stewart, Tomkiewics and Fiengold (1978)
Shields (1962)
Sternberg (1985)
Zuckerman (1990)
