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What type of selection favors the average trait?

What type of selection favors the average trait?

When environmental pressures favor the average form of the trait, selection is said to be stabilizing. Directional selection occurs when selection pressures favor one extreme of the trait distribution.

What phenotypes does stabilizing selection favors?

Stabilizing selection favors the middle phenotype, causing the decline in variation in a population over time.

What Does stabilizing selection do to a trait in a population?

Stabilizing selection causes the narrowing of the phenotypes seen in a population. This is because the extreme phenotypes are selected against, causing reduced survival in organisms with those traits. This narrowing of phenotypes causes a reduction in genetic diversity in a population.

What is the function of stabilizing selection?

Phenotypic evidence suggests that stabilizing selection, which acts to reduce variance in the population without necessarily modifying the population mean, is widespread and relatively weak in comparison with estimates from other species. Natural selection can strongly affect patterns of phenotypic variation.

Which type of natural selection shown in the figure favors average individuals?

Stabilizing selection results in a decrease of a population ‘s genetic variance when natural selection favors an average phenotype and selects against extreme variations.

Which type of selection Favours individuals with variations at opposite extremes of a trait over individuals with intermediate variations?

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.

Does stabilizing selection increase fitness?

Summary. Natural selection can cause microevolution, or a change in allele frequencies over time, with fitness-increasing alleles becoming more common in the population over generations. Stabilizing selection: Intermediate phenotypes have the highest fitness, and the bell curve tends to narrow.

Is stabilizing selection most common?

Stabilizing selection is one of three main types of natural selection in evolution. Stabilizing selection is the most common of those processes. The result of stabilizing is the over-representation in a specific trait.

Why is stabilizing selection more common?

Stabilizing selection is arguably the most common method of natural selection that occurs in plants and animals, as it essentially just reinforces the traits of animal populations that are already well adapted to that environment, rewarding organisms that have reliable, enduring phenotypes.

Does stabilizing selection favor homozygotes?

When selection favors an intermediate phenotype (such as pink heterozygotes) rather than one at the extremes (such as red and white homozygotes), it is known as stabilizing selection. If the homozygotes are favored over the heterozygotes, this is called disruptive selection.

Why is stabilizing selection most common?

What is stable during stabilizing selection?

What is stable during stabilizing selection? The population mean phenotype. Average fitness in the population would decrease. Population would eventually go extinct. Can natural selection occur in a population that is declining, and possibly going extinct.