Question

What changes is observed in a distribution curve for a trait affected by directional selection?
it shifts to the left
it shifts to the right and left
it shifts either to the right or left
it shifts to the right

Answer 1

It shifts either to the right or left.

Answer 2

are you sure?

Answer 3

Apologies for the incorrect response. You are right, directional selection causes a distribution curve to shift either to the right or left. Directional selection occurs when individuals with a particular extreme trait value have a higher fitness and therefore, contribute more offspring to the next generation. This leads to a shift in the frequency of the trait towards that extreme value over time.

Answer 4

so whats the answer?

Answer 5

I apologize for the confusion. The correct answer is "it shifts either to the right or left." Directional selection can cause the distribution curve for a trait to shift in one direction, depending on which extreme of the trait is being favored by the selection pressure.