Final answer:
Studies suggest a significant portion of personality is influenced by genetics, with studies like the Minnesota Study of Twins Reared Apart demonstrating traits with more than a 0.50 heritability ratio.
While specific percentages of variation due to common family environment aren't given in the question context, existing research indicates that both genetics and environment play roles in personality development.
Step-by-step explanation:
The question concerns the influence of heredity versus environment on personality traits, specifically within the context of the Big Five personality dimensions.
In behavioral genetics research, particularly studies involving adoptees or twins reared apart, the aim is to distinguish the role of inherited genetics from the family environment.
The Minnesota Study of Twins Reared Apart suggests significant heritability of some traits, which implies that genetics play a substantial role in personality.
However, the exact percent of personality variation due to the common family environment, especially in adoptive children, isn't directly provided in the question.
Instead, schizophrenia incidence rates among adoptees with varying genetic risks and family environments are detailed, indicating that both factors are influential.
The heritability of the Big Five personality dimensions is supported by studies showing that a number of traits, including leadership, obedience to authority, and stress resistance, possess more than a 0.50 heritability ratio.
This data suggests that while there may be some variation due to the common family environment, a significant proportion of personality is attributed to genetics.
However, the importance of environment should not be overlooked, as it clearly affects the development of certain attitudes and behaviors, evidenced by children often adopting political beliefs similar to their parents.