Flynn effects not genetic and unrelated to race differences.
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Black or African American↗
Biomedical subjects
J P Rushton
Publications and source records attributed to J P Rushton.
Self-report delinquency and violence in adult twins.
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Adult↗
Race, genetics, and human reproductive strategies.
The international literature on racial differences is reviewed, novel data are reported, and a distinct pattern is found. People of east Asian ancestry and people of African ancestry average at opposite ends of a continuum, with people of European ancestry averaging intermediately, albeit with much variability within each major race. The racial matrix emerges from measures taken of reproductive behavior, sex hormones, twinning rate, speed of physical maturation, personality, family stability, brain size, intelligence, law abidingness, and social organization. An evolutionary theory of human reproduction is proposed, familiar to biologists as the r-K scale of reproductive strategies. At one end of this scale are r-strategies, which emphasize high reproductive rates; at the other end are K-strategies, which emphasize high levels of parental investment. This scale is generally used to compare the life histories of widely disparate species, but here it is used to describe the immensely smaller variations among human races. It is hypothesized that, again on average, Mongoloid people are more K-selected than Caucasoids, who are more K-selected than Negroids. The r-K scale of reproductive strategies is also mapped on to human evolution. Genetic distances indicate that Africans emerged from the ancestral hominid line about 200,000 years ago, with an African/non-African split about 110,000 years ago, and a Caucasoid/Mongoloid split about 41,000 years ago. Such an ordering fits with and explains how and why the variables cluster.
Biological Evolution↗
Brain size matters: a reply to Peters.
Peters (1993) claimed that published research on brain size and IQ is flawed because it did not meet his list of "minimum conditions" that (a) subjects should be matched for height, weight and age, (b) analyses should be conducted separately within sex, (c) subjects should not vary in prenatal and nutritional history, (d) people with IQS appreciably below the population mean of 100 should not be studied, and (e) brain size measures should be done "blind". However, these "conditions" have either been met or are unnecessary and/or inappropriate. We show, contrary to Peters' claims, that (a) brain size is related to mental abilities, (b) brain size varies by sex and race, and (c) mental abilities vary by sex and race. Finally, we suggest that brain size constraints on behavioural complexity may be best understood from an evolutionary perspective.
Behavior↗
Race and crime: international data for 1989-1990.
The rate of murder, rape, and serious assault per 100,000 members of the population was tabulated for 76 countries from the 1989-1990 International Crime Statistics published by INTERPOL. Following previous research the countries were grouped into the three major populations of Asian, Caucasian, and African. Consistent with previous evidence the results showed that crime rates are highest for countries with predominantly African populations, lowest for those with predominantly Asian populations, and in-between for those with predominantly Caucasian populations. The 23 countries with predominantly African populations reported twice as high a rate for each type of crime as the 41 countries with predominantly Caucasian populations and over three times as high a rate as the 12 countries with predominantly Asian populations. Summing the crimes gives figures, respectively, of 240, 75, and 32 violent crimes per 100,000 population.
Cross-Cultural Comparison↗
Contributions to the history of psychology: XC. Evolutionary biology and heritable traits (with reference to oriental-white-black differences): the 1989 AAAS paper.
Genetic distance estimates calculated from DNA sequencing indicate that in years since emergence from the ancestral hominid line, Mongoloids = 41,000, Caucasoids = 110,000, and Negroids = 200,000. Data also show that this succession is matched by numerous other differences such that Mongoloids > Caucasoids > Negroids in brain size and intelligence (cranial capacity = 1448, 1408, 1334 cm3; brain weight = 1351, 1336, 1286 gm.; millions of excess neurons = 8900, 8650, 8550; IQ = 107, 100, 85); maturational delay (age to walk alone, age of first intercourse, age of death); sexual restraint (ovulation rate, intercourse frequencies, sexually transmitted diseases including AIDS); quiescent temperament (aggressiveness, anxiety, sociability); and social organization (law abidingness, marital stability, mental health). This pattern is ordered by a theory of r/K reproductive strategies in which Mongoloids are posited to be more K-selected than Caucasoids and especially more than Negroids. (K-selected reproductive strategies emphasize parental care and are to be contrasted with r-selected strategies which emphasize fecundity, the bioenergetic trade-off between which is postulated to underlie cross-species differences in brain size, speed of maturation, reproductive effort, and longevity.) It is suggested that this pattern came about because the ice ages exerted greater selection pressures on the later emerging populations to produce larger brains, longer lives, and more K-like behavior. One theoretical possibility is that evolution is progressive and that some populations are more "advanced" than others. Predictions are made concerning economic projections and the spread of AIDS.
Asian People↗
A response to C. Owen Lovejoy.
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HIV Infections↗
Race, brain size, and intelligence: another reply to Cernovsky.
Five sets of observations require explanation. Firstly, within both black and white populations there is a small positive correlation between IQ and brain size whether or not there is control for body size. Secondly, racial differences in average brain size occur such that Mongoloids greater than Caucasoids greater than Negroids especially with control for body size. Thirdly, mammals with larger brains relative to their bodies perform better on learning tasks than mammals with smaller brains relative to their bodies. Fourthly, average racial differences on measures of cognitive performance parallel the differences in average brain size. Fifthly, average racial differences on numerous other traits parallel the differences in intelligence and brain size. It is incumbent on scientists to explain these facts.
Black or African American↗
Race, brain size, and intelligence: a reply to Cernovsky.
Cernovsky's 1990 critique of my work on the relation between brain size and IQ inadequately presents my position. I did not address the issue of sex differences in brain size nor did I conclude that "women are less intelligent than men" (p. 337). In the autopsy study cited by Cernovsky, it was concluded that, when body size is controlled, the male-female difference in brain size is removed but the black-white difference in brain size remains. Cernovsky also ignores much additional data, including that Mongoloid populations have larger and heavier brains than Caucasoids. Here, I review evidence on the relation between (a) brain size and race and (b) brain size and intelligence. Data are also tabulated for personality, speed of maturation, and sexuality, on all of which the Caucasoid average consistently falls between those of Mongoloids and Negroids. This ordering may be explained by a gene-based evolutionary theory of r/K reproductive strategies in which Mongoloids are more K-selected than Caucasoids and Caucasoids more than Negroids.
Black People↗
Population differences in susceptibility to AIDS: an evolutionary analysis.
Previously we have reported population differences in sexual restraint such that, higher socio-economic status greater than lower socio-economic status, and Mongoloids greater than Caucasoids greater than Negroids. This ordering was predicted from a gene-based evolutionary theory of r/K reproductive strategies in which a trade-off occurs between gamete production and social behaviors such as intelligence, law-abidingness, and parental care. Here we consider the implications of these analyses for sexual dysfunction, including susceptibility to AIDS. We conclude that relative to Caucasians, populations of Asian ancestry are inclined to a greater frequency of inhibitory disorders such as low sexual excitement and premature ejaculation and to a lower frequency of sexually transmitted diseases including AIDS, while populations of African ancestry are inclined to a greater frequency of uninhibited disorders such as rape and unintended pregnancy and to more sexually transmitted diseases including AIDS.
Acquired Immunodeficiency Syndrome↗
Relation between aging and rated teaching effectiveness of academic psychologists.
Within a combined cross-sectional and longitudinal design, several analyses showed that student-rated teaching effectiveness in university professors declined with age. For 106 full-time psychology teachers, aged 26 to 55, who were studied for time periods ranging from 2 to 15 years, an overall negative correlation of r = -.33 (p less than .05) was found between age and general teaching effectiveness. A similar decrement with age occurred for items measuring specific teaching behaviors. Age accounted for 8% of the variance in general teaching effectiveness.
Achievement↗
Toward a theory of human multiple birthing: sociobiology and r/K reproductive strategies.
Using symbols from population biology, a continuum of reproductive strategies can be distinguished ranging from r, the production of large numbers of offspring provided with minimal care, to K, the production of few offspring nurtured intensively. While all humans are at the K end of the continuum, some are proposed to be more so than others. If multiple egg production is part of an r-reproductive strategy, certain facts may be ordered. Compared to mothers of singletons, for example, mothers of DZ twins have a lower age of menarche, a shorter menstrual cycle, a higher number of marriages, a higher rate of coitus, more illegitimate children, a closer spacing of births, a greater fecundity, more wasted pregnancies, a larger family, an earlier menopause, and an earlier mortality. Further, all twins have a shorter gestation period, a lower birth weight, and a greater incidence of infant mortality, with DZ twins having a greater frequency of health disorders, a higher mortality rate, and a lower rate of enrollment in volunteer registries. Multiple birthing also occurs more frequently in families of lower than of higher social status, and in those of African than of European and especially than of Oriental descent.
Animals↗
Evidence for an aggressive (and delinquent) personality.
An aggressive (and delinquent) personality can be shown to exist when observations are made across a large enough sampling of exemplars. Arguments against the existence of such a personality are based on a failure to use sufficiently aggregated measures. Numerous estimates are preferable in order to average out idiosyncratic variance thereby leaving a clearer view of underlying dimensions of behaviour. We illustrate the usefulness of this principle and suggest that consistent patterns of individual and group differences in aggression are to be found, are associated with delinquent behaviour, and are moderately heritable.
Aggression↗
Distal-proximal approaches to aggression: a rejoinder to Campbell, Muncer & Bibel.
Both consistency and variability exist in behaviour. While those who focus on inter-individual differences accept that there is also intra-individual variation, the opposite appears to be less true. A time continuum of levels of explanation is offered, and a recent adoption study corroborates the heritability of aggression.
Adoption↗
An evolutionary theory of health, longevity, and personality: sociobiology and r/K reproductive strategies.
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Animals↗