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Reddish Egret populations in the U.S. Were hunted to near extinction in the early 1900s and the majority of survivors were the dark-feathered morph. This would be an example of:

User SecureFish
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Final answer:

The survival of the dark-feathered Reddish Egrets under heavy hunting pressure is an example of directional selection, akin to the evolution of the peppered moth in industrial England.

Step-by-step explanation:

The case of the Reddish Egret populations being hunted to near extinction, with the majority of survivors being the dark-feathered morph, is an example of directional selection. In directional selection, environmental pressures lead to the prevalence of a particular trait within a population that provides some advantage, in this case, likely offering better camouflage or another survival benefit not specified in the question. A very similar historical case of directional selection is the well-documented evolution of the peppered moth in England following the Industrial Revolution, where darker moths became more prevalent due to their improved camouflage against soot-covered trees.

User Ninjaxor
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Answer:

This would be an example of Directional Selection

Explanation:

Natural selection is the result of the phenotype-environment interaction which determines gene destiny in space and time, selecting beneficial alleles and increasing their frequency in the population.

Directional selection increases the proportion of individuals with an extreme phenotypic trait. This selection presents more frequently in those cases in which interactions between living organisms and the environment modify in the same direction.

In the exposed example, Reddish Egret populations were under hunting pressure, which drove them to increase the frequency of dark-feathered individuals, as well as the frequency of the allele codifying for this trait. Dark individuals were the ones that got to survive hunting, they could reproduce and increase in number.

User Trenthaynes
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