Overall, this study revealed majors findings with respect to the genetics and environmental influences of certain characteristics. When comparing identical and fraternal twins, the characteristics are more similar in identical twins proving that genes play a large role in influencing characteristics. When comparing identical twins raised apart to identical twins raised together, data clearly indicates that identical twins raised together are more similar in characteristics, indicating that genes play a larger role than environment in influencing characteristics. Criticisms of this study include “Equal environment assumption” criticism that argues Bouchard and Lykken the MZ and DZ twins raised together develop in identical environments. (Lykken & Bouchard, 1990)