Analyzes and refutes two propositions of H.J. Eysenck: (a) that intellectual differences in our culture are overwhelmingly determined by genetic factors, and (b) that the 15-point mean I.Q. gap between black and white Americans is largely determined by genetic factors. (JM)

Genetic effects on specific cognitive abilities as distinct from those on general cognitive ability were studied in 302 pairs of twins (some reared together, some apart) from the Swedish Adoption/Twin Study of Aging. Overall, results showed significant genetic influence on specific abilities independent of influence on general ability. (SLD)

Evidence on the poorer spatial visualization ability in various Negro populations compared to the White populations and on the direction and magnitude of sex differences in spatial ability relative to other abilities suggests the genetic hypothesis that spatial ability is enhanced by a sex-linked recessive gene and that, since the 20-30 percent…

Scarr and Weinberg's results (Intelligence, 1977) are compared to those of similar adoption studies and found to be quite similar, despite the transracial adoption patterns in Scarr and Weinberg's sample. The author also suggests that the major contribution of behavioral genetics to psychology may be our increased understanding of the environment.…

A study of twins was conducted to determine the presence of an hereditary component in short term memory and in three aspects of verbal divergent thinking--flexibility, fluency, and originality. Results showed the existence of a significant genetic component in the trait of short term memory, while none was found in verbal divergent thinking. (AG)

The assumption that a singular biological resource pool embedded in the central nervous system results in differences in macrolevel outcomes because of the constraints it imposes on efficiencies of microlevel processing is refuted. Moderating effects on the causal pathways between microlevel and macrolevel performance are discussed. (SLD)

This paper is the first chapter of a book and is divided into six sections. The first section discusses race taxonomy, the Negro American's origins from Africa, and the origin of race differences. The second section investigates the genetic aspects of race differences in intellectual performance, and includes a lengthy introductory discussion on…

Composite reading performance data from 223 pairs of identical twins and 169 same-gender fraternal twins in which at least one member was classified with reading disability were subjected to multiple regression analysis. Results indicated that the genetic etiology of reading disability differs as a linear function of IQ. (Contains extensive…

Areas of agreement and disagreement concerning intellectual developmental and the problems of mental retardation espoused by the author and by Uzgiris are discussed in this paper. The importance of environmental factors, along with the genetic and/or constitutional nature of the organism on which these environmental events impinge, is seen as…

Much of our thinking about contemporary social problems reflects tacit presuppositions regarding the operation of heredity and environment in human behavior. These beliefs have important implications for practical decisions. Advances in genetics, psychology, anthropology, and other disciplines have contributed much to a clarification of the…

This book on the genetic and environmental influences on intelligence is comprised of the following papers: "The Structure of Intelligence in Relation to the Nature-Nurture Controversy," R. B. Cattell; "Theory of Intelligence," L. G. Humphreys; "Using Measured Intelligence Intelligently," P. R. Merrifield; "Intelligence: Definition, Theory, and…

This paper critically examines the portions of Arthur Jensen's books, "Genetics and Education" and "Educability and Group Differences," that concern Barbara Burks' 1928 study of adoptive families. Jensen cites the low correlations of children's IQs with measures of home environment from Burks' study as evidence that environment…