Question

What does it mean that the personality trait of shyness has a heritability factor of .40?

a. 40% of the children of a shy person will also be shy.
b. A child of two shy parents has an 80% chance of being shy.
c. If a person is shy, it's 40% the result of genes and 60% the result of environmental influences.
d. Across the human population, the variations in shyness are moderately influenced by both genetics and environmental factors.

Answer 1

The heritability factor of .40 for shyness indicates that 40% of the variation in this trait among the population is attributed to genetics, not that individual shyness is determined by such a precise genetic factor.

Step-by-step explanation:

When we say that the personality trait of shyness has a heritability factor of .40, it means that across the human population, 40% of the variation in shyness can be attributed to genetic differences, while the remaining 60% is due to environmental factors. This does not mean that in individual cases, such as with the children of a shy person, we can predict with certainty that exactly 40% of their shyness is due to genetics. Rather, it suggests that genetic factors play a moderate role in the differences in shyness among people, while environmental influences also play a significant role.