Dr.VanVliet finds that of a sample of pairs of identical twins raised together,80% were either both "owls" or both "larks." Dr.VanVliet then investigates pairs of identical twins raised in very different families,and pairs of fraternal twins raised either together or in very different families.He again records the percentage of pairs of twins raised who were either both "owls" or both "larks." Based on your text's discussion,which of the following best approximates the pattern of results he should find?
A) identical apart - 60%; fraternal together - 40%; fraternal apart - 20%
B) identical apart - 80%; fraternal together - 80%; fraternal apart - 80%
C) identical apart - 75%; fraternal together - 65%; fraternal apart - 60%
D) identical apart - 65%; fraternal together - 75%; fraternal apart - 60%

Question

Quizplus · Accepted Answer

Studies have shown that identical twins raised together have a higher concordance rate for sleep patterns (80%). However, identical twins raised in different families will have different environmental factors affecting their sleep patterns and may have a slightly lower concordance rate (around 75%). Fraternal twins, whether raised together or apart, have even lower concordance rates (around 65-60%). Choice C best approximates these patterns of results.

DrVanVliet Finds That of a Sample of Pairs of Identical