What does it mean to say that the heritability of a trait is 70 percent?
◦ Thirty percent of a person's expression of that trait is due to environmental factors.
◦ Seventy percent of a person's expression of that trait is due to heredity.
◦ Seventy percent of the variability of that trait in a group is accounted for by genetic variation.
◦ The correlation between identical twins should be approximately +0.70 for that trait.