Many topics of interest to developmental scientists are informed by behavioural genetic findings and their implications. First, behavioural genetic theory and methods will be briefly outlined. Next, findings will be illustrated by considering two disparate areas--general cognitive ability (IQ), and children's self-conceptions. These topics have…

Using a longitudinal, large-scale sample of British twins, we addressed the prediction of both cognitive abilities and behavioral adjustment from eight domains of environmental risk: minority status, socio-economic status, maternal medical factors, twin medical factors, maternal depression, chaos within the home environment, and parental feelings…

The current study examined whether socioeconomic status (SES) and chaos in the home mediate the shared environmental variance associated with cognitive functioning simultaneously estimating genetic influences in a twin design. Verbal and nonverbal cognitive development were assessed at 3 and 4 years for identical and same-sex fraternal twin pairs…

Examined nonshared environmental (NSE) influences on twin preschoolers' behavior independent of genetics. Found that within-pair parenting differences correlated with monozygotic differences in behavior. For the extreme 10 percent of the parenting-discordant and behavior-discordant distributions, average NSE effect size was 11 percent, suggesting…