In this article, it is argued that it makes sense to define and distinguish three levels of human intelligence: intelligence as genotypical potential, intelligence as actualised in environmental interaction, and intelligence as measured by tests (IQ). This raises the questions of what is meant by the term "intelligence as potential", and…

Results from a genome-wide association study (GWAS) can be used to generate a polygenic score (PGS), an individual-level measure summarizing identified genetic influence on a trait dispersed across the genome. For complex, behavioral traits, the association between an individual's PGS and their phenotype may contain bias (from geographic,…

The term "polymath" refers to a person whose expertise approaches different subject areas, to rely on complex packages of knowledge for solving problems. Famous polymaths from history include Galileo Galilei, Leonardo da Vinci, Mozart, and Albert Einstein; individuals that have impacted science, arts, humanities, and our society for…

Anorexia nervosa is a complex behavioral disorder with the highest risk of death of any psychological disorder. Between 15% and 20% of those suffering from anorexia die from complications that are attributed either directly or indirectly to self-starvation. Heritability for anorexia is around 0.5, meaning about 50% of the risk for anorexia is…

Virtuous character development in children is correlated with parenting behavior, but the role of genetic influences in this association has not been examined. Using a longitudinal twin/sibling study (N = 720; Time 1 (T1) M[subscript age] = 12-14 years, Time 3 (T3) M[subscript age] = 25-27 years), the current report examines associations among…

Crude and dangerous ideas about the genetic heritability of intelligence, and a supposed biological basis for the Black/White achievement gap, are alive and well inside the education policy process but taking new and more subtle forms. Drawing on Critical Race Theory, the paper analyses recent hereditarian writing, in the UK and the USA, and…

The conflicts between nature and nurture are brought to the fore and challenges socio-scientific decision-making in science education. The multitude of meanings of these concepts and their roles in societal discourses can impede students' development of understanding for different perspectives, e.g. on gene technology. This study problematizes…

Purpose: Behavioral genetic studies of speech fluency have focused on participants who present with clinical stuttering. Knowledge about genetic influences on the development and regulation of normal speech fluency is limited. The primary aims of this study were to identify the heritability of stuttering and high nonfluency and to assess the…

The connection that critics make between medical genetics and eugenics is historically fallacious. Activists on the political right are as mistaken as activists on the political left: Genetic screening was not eugenics in the past, is not eugenics in the present, and, unless its technological systems become radically transformed, will not be…

In this paper we assess the presence of assortative mating, gene-environment interaction and the heritability of intelligence in childhood using a twin family design with twins, their siblings and parents from 112 families. We evaluate two competing hypotheses about the cause of assortative mating in intelligence: social homogamy and phenotypic…

A behavioral genetic analysis of general writing ability was conducted using teacher assessments based on UK National Curriculum criteria for a sample of 3296 same-sex pairs of 7-year-old twins. Writing was highly heritable within the normal range (0.66) and at the low extreme (0.70). Environmental influences were almost all non-shared, with…

Reviews genetic influence on suicide. Reviews methodologies for studying the nature-nurture issue and examines their applicability to the study of suicide. Reviews research from the methodologically sound strategies. Examines work by Uematsu using an approach different from any of the conventional methodologies. (Author/ABB)

Described are turn-of-the-century (1900) efforts of E. Johnstone, Vineland Training School for the mentally retarded; H. Goddard, psychologist (also at Vineland); and C. Davenport, Carnegie Foundation biological laboratory, Coldspring Harbor; to identify the roles of genetic heredity and environmental impact, and thus to eradicate or ameliorate…

Surveyed literature on genetics and fears and phobias to determine what might be heritable. Found, for ordinary fears among the general population, heredity appears to contribute mainly to a trait of general fearfulness and may be a major reason for the strong intercorrelation among different fears. Found evidence of little environmental…

Presents interview with Thomas Bouchard, a leading researcher of identical twins reared apart. Describes major themes in the Minnesota twin research. Claims, although genetic influence is central, Bouchard pleas for the impact of environmental factors in optimal human development. Includes Bouchard's surprising experiences, current focus, and…