Parenting and children's temperament are important influences on language development. However, temperament may reflect prior parenting, and parenting effects may reflect genes common to parents and children. In 561 U.S. adoptees (57% male) and their birth and rearing parents (70% and 92% White, 13% and 4% African American, and 7% and 2% Latinx,…

This study tested implications of new genetic discoveries for understanding the association between parental investment and children's educational attainment. A novel design matched genetic data from 860 British mothers and their children with home-visit measures of parenting: the E-Risk Study. Three findings emerged. First, both mothers' and…

Intelligence test scores were obtained from parents and children in 300 adoptive families and compared with similar data available from the children's biological mothers. Results support the hypothesis that genetic variability is an important influence in the development of individual differences in intelligence. (Author/RH)

When reference cues are added to a pattern copying task, males' performance improves, but females' remains the same. This superior cue utilization may partially explain differences in spatial abilities. The present research attempts to determine the optimum locus for facilitation of copying by reference cues. (RH)

Examined family influences on vocational interest development. Hypothesized that parents with similar interests were more likely to have adolescents who also developed those interests than were parents whose interests were very divergent. To "unconfound" genetic and environmental influences, parent-child interest difference scores were compared…

Written in response to an article (Horn, 1983) that appeared in special Developmental Behavioral Genetics section of CHILD DEVELOPMENT (Volume 54), this commentary (1) notes some issues concerning Horn's analysis and interpretation of data and (2) highlights the potential for interpretational bias in behavior genetics research. (Author/BE)

In this rebuttal to Walker and Emory's commentary (also in this issue), Horn argues that the issue of the influence of environment on the average IQ of adopted children was well discussed in his article (Volume 54 of CHILD DEVELOPMENT). (BE)

Pooled sibling attachment data to compare attachment relationships to mothers for 138 sibling pairs. Found that sibling relationships were significantly concordant when classified as secure/nonsecure but not when further subcategorized. Maternal insensitivity to both siblings was associated with concordance of sibling nonsecurity. Same gender…

Measures of general cognitive ability in one- and two-year-old adopted and nonadopted infants and their parents were subjected to path analysis to estimate the contribution of genetic and environmental factors to short-term stability of mental ability. (Author/RH)

Estimates the extent to which heredity influences perceptions of childhood family environment in a sample of 58 monozygotic and 46 dizygotic pairs of adult twins who were reared apart. The data confirm the importance of genetic factors in some, but not all, measures of family environment. Environmental influences were more important than genetic…

The mother, father, and adolescent siblings from 675 families were observed interacting in problem-solving sessions. Siblings were monozygotic twins, dyzygotic twins, or full siblings in nondivorced families and full, half, and unrelated siblings in stepfamilies. Results suggested a greater genetic component to adolescent behavior than to parent…

Parents of Swedish twin pairs ages 7 to 9 years and of British twin pairs ages 8 to 16 years completed the Child Behavior Checklist. Found that genetic factors influenced aggressive antisocial behavior to a greater extent than nonaggressive antisocial behavior, which was also significantly influenced by the shared environment. There was a…

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…

Used the sibling adoption design to investigate teacher and tester ratings of child temperament. Ratings on the Colorado Childhood Temperament Inventory were obtained from a teacher and a tester for pairs of adopted and nonadoptive seven-year-old siblings. Significant genetic influence emerged for tester ratings of Activity and Sociability and for…

Investigated the degree to which individual differences in child-parent attachment were mediated by genetic, shared environmental, and nonshared environmental influences. Found an overall concordance rate of 67 percent at the secure/insecure level. Twin similarity on the continuous measure of attachment security was consistent with a modest role…