Behavioural genetics regards intelligence and educational attainment as highly heritable (genetically influenced) and polygenic (influenced by many genes) traits. Researchers in the field have moved beyond identifying whether and how much genes influence a given outcome to trying to pinpoint the genetic markers that help predict them. In more…

Little is known about the etiology of developmental change and continuity in educational achievement. Here, we study achievement from primary school to the end of compulsory education for 6000 twin pairs in the UK-representative Twins Early Development Study sample. Results showed that educational achievement is highly heritable across school…

By surveying a representative sample of Finnish parents, this study set out to compare two social representations of intelligence current in our educational discourse: the established one, "the idea of natural giftedness", and an emerging one, "the idea of the multifariousness of abilities and support for social equality." It…

The main argument of this article is that human living systems are open, dynamic, intentional systems and, therefore, are capable of building ever more complex behaviors through self-organization and self-direction. This principle underlying general human development is also applicable to the development of gifted and talented behaviors. These…

Taylor (1980) claims to show that the similarity in IQ between monozygotic twins reared apart found in prior studies is due to similarity in their environments. A reanalysis using Taylor's classification of environments but an alternative IQ measure shows that his findings do not constructively replicate. (Author/RD)

Correlations on subscales of Wechsler intelligence quotient tests and the Revised Beta Examination were obtained for biologically related and unrelated individuals in 181 adoptive families in the Texas Adoption Project. Generally higher correlations for biologically related individuals support the importance of genetic influence in intellectual…

Virtual twins are unrelated siblings of the same age who are reared together from early infancy (UST-SA). Study uses a sample of 90 UST-SA pairs to comparatively assess the similarity of IQ subtest profile correlations for UST-SAs and twin pairs. Findings support explanatory models of intelligence that include genetic factors, demonstrating that…

Examined the origins of high general cognitive ability (g) in twins who were participating in the MacArthur Longitudinal Twin Study. Formed high g groups from the 19th percentile and above at each age. Results suggested increasing genetic influence and increasing genetic stability from 14 to 36 months and substantial genetic influences with…

Pairs of genetically unrelated children reared as same-age siblings offer a design for investigating genetic and environmental influences on behavior. Results with 21 pairs support an explanatory model of intelligence that includes genetic factors. Shared environment appeared to have a very small effect on intellectual development. (SLD)

Hypothesizes that a child's realization of genetic potential for intellectual development depends on socioeconomic environment. Peabody Picture Vocabulary Test results were examined for a large sibling sample of African American and White adolescents from the National Longitudinal Study of Adolescent Health. When SES factors were considered…

This paper presents the results of a study which examined heritability ratios for the major ethnic and socioeconomic groups in the Los Angeles Unified School District. Scores on three measures (the Cooperative Primary Reading Test, the Comprehensive Test of Basic Skills, and a composite set of intelligence tests) were compared for twins from…

A psychobiosocial model that is based on the inextricable link between the biological bases of intelligence and environmental events is proposed as an alternative to nature/nurture dichotomies. Societal implications and applications to teaching and learning are suggested. (MMU)

A computer scan of ACT Assessment records identified 3,427 sets of twins. The Hardy-Weinberg rule was used to estimate the proportion of monozygotic twins in the sample. Matrices of genetic and environmental influences were produced. The heaviest loadings were clearly in the genetic matrix. (SJL)

A battery of "g" loaded mental ability tests was administered to 274 Bedouin children and adolescents, full and half siblings from 106 families. Results demonstrate internal validity for the tests in this cultural context and support the idea that shared family environment is a strong determinant of sibling similarity for children in the…

The effects of family background on adolescents' IQ, aptitude, and school achievement test scores challenge some of the usual beliefs about the fairness of achievement rather than IQ tests, and the role of genetic differences among individuals and social class groups in academic achievements. Subjects included 115 adoptive families with adolescent…