how is it classified?
It can be classified in several different ways, such as by its effect on a trait, on genetic diversity, by the life cycle stage where it acts, by the unit of selection, or by the resource being competed for.
Natural selection
Selection can be classified in several different ways, such as by its effect on a trait, on genetic diversity, by the life cycle stage where it acts, by the unit of selection, or by the resource being competed for.
where does all the natural variation necessary for natural selection come from This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. what is this all about? Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. were there any theories based on it? Yes, Darwin's theory.
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Natural selection [SEP] Classification
Natural selection can act on any heritable phenotypic trait, and selective pressure can be produced by any aspect of the environment, including sexual selection and competition with members of the same or other species. However, this does not imply that natural selection is always directional and results in adaptive evolution; natural selection often results in the maintenance of the status quo by eliminating less fit variants. Selection can be classified in several different ways, such as by its effect on a trait, on genetic diversity, by the life cycle stage where it acts, by the unit of selection, or by the resource being competed for.