What is the Difference Between Disruptive Selection and Stabilizing Selection?

The main differences between disruptive selection and stabilizing selection are as follows:

Extremes vs. Intermediates: Stabilizing selection eliminates extremes (both the lowest and highest values of the trait), whereas disruptive selection eliminates intermediates (the average or intermediate phenotypes).
Speciation: Stabilizing selection does not lead to speciation, while disruptive selection can lead to speciation, as it may cause the formation of two new populations with distinct phenotypes.
Effect on Genetic Variance: Stabilizing selection reduces the genetic variance of a population, as it eliminates both extreme phenotypes. In contrast, disruptive selection can increase genetic variance within the population, as it selects against the average or intermediate phenotypes.
Adaptation: Stabilizing selection occurs when the population stabilizes on a particular trait value, making the individuals more adapted to the environment. Disruptive selection, on the other hand, acts against individuals in the middle of the trait distribution, potentially favoring populations with more diverse phenotypes.

In summary, stabilizing selection favors the middle of a trait distribution and eliminates extreme values, while disruptive selection favors the extremes and eliminates the middle values. Stabilizing selection tends to make populations more homogeneous, while disruptive selection can lead to increased diversity and even speciation.

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What is the Difference Between Disruptive Selection and Stabilizing Selection?

Comparative Table: Disruptive Selection vs Stabilizing Selection

Disruptive selection and stabilizing selection are two types of natural selection processes that influence the genetic variance of a population. Here is a table highlighting the differences between them:

Feature	Disruptive Selection	Stabilizing Selection
Definition	Disruptive selection favors both extreme phenotypes over intermediate phenotypes, increasing the genetic variance of the population.	Stabilizing selection favors average phenotypes in a population and eliminates both types of extreme phenotypes, decreasing the population's genetic variance.
Genetic Variance	Increases the population's genetic variance.	Decreases the population's genetic variance.
Phenotypes	Favors both extreme phenotypes.	Favors intermediate phenotypes and eliminates extreme phenotypes.
Examples	A population of plants with medium height is favored, as both short and tall plants have lower fitness due to sunlight and wind damage, respectively.	A population of mice that live in the woods, natural selection will tend to favor individuals that best blend in with the forest floor, disfavoring extreme shades of fur.

In summary, disruptive selection increases the genetic variance of a population by favoring both extreme phenotypes, while stabilizing selection decreases the genetic variance by favoring intermediate phenotypes and eliminating extreme phenotypes.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.