When the range of environments to which twins are exposed is restricted, heritability estimates
A) fail to take into account that twins reared apart often live in disadvantaged adoptive and foster families.
B) underestimate the role of environment and overestimate the role of heredity.
C) overestimate the role of environment and underestimate the role of heredity.
D) grant an equal role to heredity and environment. .

Question

Quizplus · Accepted Answer

When the range of environments to which twins are exposed is restricted, heritability estimates underestimate the role of environment and overestimate the role of heredity. This is because the restricted range of environments limits the variability in environmental factors that may be contributing to differences in traits. Thus, any differences that are observed between twins are more likely to be driven by genetic factors rather than environmental factors, leading to an overestimation of heritability.

When the Range of Environments to Which Twins Are Exposed