If friendliness was a genetically influenced trait, identical twins would be more likely to be similar on the trait of friendliness than fraternal twins would be.

Question

Quizplus · Accepted Answer

Identical twins share 100% of their genes while fraternal twins share only 50% of their genes on average. Therefore, if friendliness was genetically influenced, identical twins would be more likely to have similar levels of friendliness than non-identical (fraternal) twins.

If Friendliness Was a Genetically Influenced Trait, Identical Twins Would