How are directional selection and disruptive selection alike?

A shift in the allele frequency in the population results from selection forcing more individuals to have the favorable adaptation, which is known as directional selection. It is defined as the selection for a specific extreme phenotype in the population as opposed to the other phenotypes.

Over time, a distinct difference can be observed in the population, and the population may separate due to their extreme differences in that particular phenotype. Disruptive selection occurs when the population is subjected to selection pressures that select against the average phenotype and the extreme phenotypes are selected for.

The extreme phenotypes are selected for in both kinds of selections, while the average phenotype is rejected.

Both disruptive and directional selection can lead to evolutionary changes in the characteristics of the population; they are similar in that they both cause changes over time in the frequency distribution of traits within a population.