Chapter 31, Problem 1MM

Summary Introduction

Concept introduction: Intelligence is not a quantitative measure such as height and weight. However, it is a qualitative measure that is defined by the intelligence test measures. Intelligence in general is defined as the person’s ability to acquire knowledge from experience, problem solving ability, and use of knowledge to adapt and acclimatize to new situations that are encountered.

Answer to Problem 1MM

Correct answer: Identical twins, but not other siblings, have nearly identical intelligence test scores is the strongest support for heredity’s influence on intelligence. Therefore, option a. is correct.

Explanation of Solution

Reasons for the correct statement:

Genetics and environment influences the intelligence of individuals. Haworth et al, 2009 said that the intelligence test scores of identical twins who were raised together were nearly similar to those of the results when an individual took the same test twice.

Option a. is given as “identical twins, but not other siblings, have nearly identical intelligence test scores”

As, identical twins, but not other siblings, have nearly identical intelligence test scores, is an evidence that points to genetic influence on intelligence, option a. is correct.

Reasons for the incorrect statements:

Option b. is given as “the correlation between intelligence test scores of fraternal twins is not higher than that for other siblings”. The correlation between the intelligence test scores of fraternal twins is higher than that for other siblings. Therefore, option b. is incorrect.

Option c. is given as “mental similarities between adopted siblings increase with age”. Mental similarities between the adopted siblings decrease with age. Therefore, option c. is incorrect.

Option d. is given as “children in impoverished families have similar intelligence scores”. Children in impoverished families have dissimilar intelligence scores. Therefore, option d. is incorrect.

Hence, options b., c., and d. are incorrect.

Conclusion

 Identical twins, but not other siblings, have nearly identical intelligence test scores is the strongest support for heredity’s influence on intelligence.