Answer:
There is an increase in wool length and a little decrease in body size
Explanation:
Given that:
the narrow-sense heritability of wool length in a breed of sheep is 0.92; &
the narrow-sense heritability of body size is 0.87.
As these traits approaches 1, the higher the rate that helps them to provide a positive feedback for selection.
The question proceeds by stating that " The genetic correlation between wool length and body size is –0.84."
You see, the functionality of this negative (-0.84) genetic correlation tends to create an imbalance between these heritable traits. As such, there is a shift in the paradigm in which one traits tends to increase and the other trait to decrease.
Now, if a breeder selects a sheep with longer wool, there is an increase in wool length since he selects it although there will be a little decrease in body size due to the negative genetic correlation effect between the two heritable traits.
