A researcher tracks the escape behavior of a population of squirrels on campus across two generations.When she plots the escape behavior of the offspring generation against the parental behavior,she notes that the offspring's behavior exactly matches the parental behavior.Nonetheless,the narrow-sense heritability equals zero.How can the heritability equal zero in this example?
A)The additive genetic variance equals zero.
B)All the escape behavior alleles are fixed in the population.
C)There is no phenotypic variation.
D)A and B
E)All of the above

Question

Quizplus · Accepted Answer

If all the alleles for escape behavior are fixed in the population, then there is no variation for the offspring's behavior to deviate from the parental behavior, resulting in a heritability of zero. Additionally, since there is no variation, there is no additive genetic variance. Therefore, options A and B are also correct. Option C cannot be true since there is clear phenotypic variation between the parental and offspring populations, but the offspring simply did not deviate from the parental behavior.

A Researcher Tracks the Escape Behavior of a Population of Squirrels