Explain the concept of ‘natural selection’ and what it really means

Explanation:

Instead of the term natural selection used by Darwin, Herbert Spencer used survival of the fittest. According to Darwin, out of the vast number of individuals which complete for a place in the world, only those having advantageous variations survive and reproduce. Those who do not have these variations die. Thus, the nature exercises it's selection on only those individuals, which are the fittest; only they survive and reproduce successfully. The process is called Natural Selection.

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