Which form of natural selection favors individuals on both extremes of a phenotypic range?

Disruptive selection is the type of natural selection that favors individuals at both extremes of a phenotypic range while selecting against the average or intermediate forms. This can lead to a bimodal distribution of traits within a population. Essentially, in environments where resources are limited or the extremes have an advantage, individuals that possess traits at the extreme ends of the phenotypic spectrum—whether it is for body size, coloration, or any other measurable characteristic—may have a higher fitness.

For example, in a habitat with two distinct niches, such as a light and a dark environment, organisms that are either very light or very dark might be better suited for survival compared to those that are intermediate in coloration. As a result, over time, disruptive selection can lead to an increase in the frequency of extreme traits within the population, potentially resulting in speciation if the extremes become distinct enough.

In contrast, directional selection involves favoring individuals at one end of the phenotypic spectrum, while stabilizing selection tends to favor intermediate traits over extremes, leading to reduced variation. Biotic potential refers to the maximum reproductive capacity of an organism under optimal environmental conditions and does not directly relate to phenotypic selection processes.