SUMMARY
1. Research suggests both genetics and the environment have an influence
on the development of adult personalities. Psychologists use a variety
of methods to determine the extent to which personality is inherited,
most notably the twin-study method. However, questions surface when
interpreting these studies, particularly with some of the underlying
assumptions of the methods. Nonetheless, the cumulative evidence argues
strongly for a significant heritability component in adult personality.
2. Extraversion-introversion is probably the most widely researched aspect
of Eysenck ’s personality theory. Evidence indicates that this personality
variable has a large heritability component. Consistent with Eysenck ’s
theory, researchers find extraverts seek out stimulating environments and
perform better in these environments than introverts. Research also finds
that extraverts are generally happier than introverts.
3. Evolutionary personality theory predicts that men and women look for
different features when selecting romantic partners. Consistent with this
view, research shows that men are more likely to consider physical at-
tractiveness when selecting a dating partner or spouse. In addition, menare more likely to prefer a younger partner. Studies also indicate that
women prefer a man who possesses the resources necessary for raising a
family. Cross-cultural research suggests that these preferences may be
universal.
KEY TERMS
twin-study method (p. 253)
MEDIA RESOURCES
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glossary, flashcards, and more.Summary 273