This paper reports physical and behavioral similarities and differences in a pair of 18-year-old monozygotic (MZA) female twins, raised apart from birth in dramatically different cultures: South Korea and the United States. The main outcome measures included life history characteristics (e.g., age at separation, age at reunion), physical and health-related traits (e.g., height, weight, body mass index, age at menarche, illnesses), and behavioral traits (e.g., IQ, special mental abilities, personality traits, dietary preferences). Similarities in some physical characteristics, as well as differences, were noted. High levels of concordance were obtained for IQ and for two special mental ability measures. Selected personality traits presented a mixed picture with respect to concordance and discordance, and dietary preferences showed some unexpected similarities. The findings are discussed with reference to genetic and cultural influences on development.
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