Diversifying (or disruptive) selection: Diversifying selection occurs when extreme values for a trait are favored over the intermediate values. This type of selection often drives speciation. Diversifying selection can also occur when environmental changes favor individuals on either end of the phenotypic spectrum.

What happens to the mean in disruptive selection?

Disruptive selection can lead to a bimodal distribution of trait values and therefore can result in an increase in the variance of a trait without a change in its mean.

How does selection change a population over time?

Natural selection is the process through which populations of living organisms adapt and change. ... Over time, these advantageous traits become more common in the population. Through this process of natural selection, favorable traits are transmitted through generations.