Paleontologist observed changes in the sizes of black bears as the environment changed during warm periods between Ice Age is most black bears were small during Ice Age. Most black bears were large which type of selection is this and how would graph of the distribution curve of black bear size change, as earth moved out of an ice age.
A stabilizing the curve would become taller in the middle and shorter on each side
B directional, the curve would shift to the right
C disruptive the curve would break into two peaks with a dip in the middle
D the curve would shift to the left
The correct answer is A) stabilizing. In this case, the majority of black bears were small during the Ice Age, but as the environment changed during warm periods, the sizes of black bears started to vary more and became larger. Stabilizing selection occurs when extreme traits are selected against, favoring the average or intermediate traits.
Therefore, the distribution curve of black bear size would become taller in the middle and shorter on each side. This means that there would be more individuals with average or intermediate sizes and fewer individuals with very small or very large sizes.