Question

A genetics researcher determines that the broad-sense heritability of height among Southwestern University undergraduate students is 0.90. Which of the following conclusions would be reasonable? Explain your answer.

1) Since Sally is a Southwestern University undergraduate student, 10
2) Ninety percent of variation in height among all undergraduate students in the United States is due to genetic differences.
3) Ninety percent of the height of Southwestern University undergraduate students is determined by genes.
4) Ten percent of the variation in height of Southwestern University undergraduate students is determined by variation in nongenetic factors.
5) Because the heritability of height among Southwestern University students is so high, any change in the students' environment will have minimal impact on their height.

Answer 1

A heritability of 0.90 in height among a specific group indicates that 90% of the variation is due to genetics, and 10% is due to environmental factors within that group, not across all students or each individual trait.

Step-by-step explanation:

The broad-sense heritability of height among Southwestern University undergraduate students being 0.90 suggests that 90% of the variation in height within this specific population is due to genetic differences. This means that point 4) Ten percent of the variation in height of Southwestern University undergraduate students is determined by variation in nongenetic factors would be a reasonable conclusion.

Heritability does not imply that 90% of an individual's height is determined by their genes, nor does it apply to all undergraduate students in the United States, which invalidates point 2) and point 3) as reasonable conclusions. Point 5), which concerns the impact of environmental changes on height, assumes that heritability is a fixed value; however, heritability can vary based on the population and environment, so this conclusion may not be completely accurate.