Alos, refers to differential survival and reproduction of classes of organisms that differ from one another in on or more usually heritable characteristics. Through this process, the forms of organisms in a population that are best adapted to their local environment increase in frequency relative to less well-adapted forms over a number of generations. This difference in survival and reproduction is not due to chance. Natural selection is Darwin's theory that evolution favors those plants and animals best suited to their living conditions . It is a key concept in Darwin's theory of evolution. Because more members of a species are born than environmental resources can support, nature selects those with characteristics most conducive to survival under the circumstances, which allows them to reproduce. Moreover, Natural selection refers to the evolutionary process by which nature selects traits that best enable organisms to survive and reproduce in particular environmental niches.
List of books: Natural,selection