<P> Through studies of identical twins separated at birth, one - third of their creative thinking abilities come from genetics and two - thirds come from learning . Research suggests that between 37 and 42 percent of the explained variance can be attributed to genetic factors . The learning primarily comes in the form of human capital transfers of entrepreneurial skills through parental role modeling . Other findings agree that the key to innovative entrepreneurial success comes from environmental factors and working "10,000 hours" to gain mastery in entrepreneurial skills . </P> <P> Evidence from behavioral genetic research suggests that family environmental factors may have an effect upon childhood IQ, accounting for up to a quarter of the variance . The American Psychological Association's report "Intelligence: Knowns and Unknowns" (1995) states that there is no doubt that normal child development requires a certain minimum level of responsible care . Here, environment is playing a role in what is believed to be fully genetic (intelligence) but it was found that severely deprived, neglectful, or abusive environments have highly negative effects on many aspects of children's intellect development . Beyond that minimum, however, the role of family experience is in serious dispute . On the other hand, by late adolescence this correlation disappears, such that adoptive siblings no longer have similar IQ scores . </P> <P> Moreover, adoption studies indicate that, by adulthood, adoptive siblings are no more similar in IQ than strangers (IQ correlation near zero), while full siblings show an IQ correlation of 0.6 . Twin studies reinforce this pattern: monozygotic (identical) twins raised separately are highly similar in IQ (0.74), more so than dizygotic (fraternal) twins raised together (0.6) and much more than adoptive siblings (~ 0.0). Recent adoption studies also found that supportive parents can have a positive effect on the development of their children . </P> <P> Personality is a frequently cited example of a heritable trait that has been studied in twins and adoptees using behavioral genetic study designs . The most famous categorical organization of heritable personality traits were created by Goldberg (1990) in which he had college students rate their personalities on 1400 dimensions to begin, and then narrowed these down into "The Big Five" factors of personality--Openness, conscientiousness, extraversion, agreeableness, and neuroticism . The close genetic relationship between positive personality traits and, for example, our happiness traits are the mirror images of comorbidity in psychopathology . These personality factors were consistent across cultures, and many studies have also tested the heritability of these traits . </P>

Who postulated the nature versus nurture hypothesis postulated the nature versus nurture hypothesis