Why is natural selection, as a scientific model, applied at the population level and NOT at the individual level?

Individuals cannot change inheritable traits.

Pressures apply only to groups of individuals and not to individuals themselves.

Significant traits are shared by all individuals in a population.

Mutations occur so rarely that they are detectable only at the population level.

Scientific model of natural selection applies to groups because pressures are experienced only to groups of individuals and not to individuals themselves.

Explanation:

Natural selection, linked to the evolution proposed by Charles Darwin, refers to the way in which different genotypes are presented in a population, subject to reproduction. In simple terms, genetic variations in a population, determined by the need to adapt to their environment, produce changes in the genotypic expression of later generations.

Groups of individuals of a species must be subject to the same environmental pressure and changes in their environment for natural selection to occur and be inheritable to subsequent generations. Changes experienced by a single individual are not significant for offspring within a population.

For natural selection to occur there must be certain conditions:

Currently, the modern conception of natural selection discusses whether this selection occurs at the group level.

Learn more:

Natural selection and evolution link

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