The correlation of IQs between identical twins reared together is 0.86 and drops to 0.72 when the identical twins are reared apart.Psychologists who emphasize genetics take this to mean that
A) genetics plays no role in determining intelligence.
B) IQs tend to follow the mother.
C) differences in adult intelligence are roughly 50 percent hereditary.
D) the first few months of a baby's life are critical in the formation of intelligence.

Question

Quizplus · Accepted Answer

The high correlation (0.86) between IQs of identical twins reared together suggests that genetics plays a significant role in determining intelligence. The lower correlation (0.72) when the twins are reared apart indicates that environmental factors also contribute to differences in intelligence, but genetics still accounts for roughly 50 percent (or more) of individual differences in IQ.

The Correlation of IQs Between Identical Twins Reared Together Is