How biodiversity is affected by speciation, disruptive, stabilizing, and directional selection?

There are several ways selection can affect population variation:

stabilizing selection

directional selection

diversifying selection

frequency-dependent selection

sexual selection

As natural selection influences the allele frequencies in a population, individuals can either become more or less genetically similar and the phenotypes displayed can become more similar or more disparate. In the end, natural selection cannot produce perfect organisms from scratch, it can only generate populations that are better adapted to survive and successfully reproduce in their environments through the aforementioned selections.

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