natural selection

American  

[nach-er-uhl si-lek-shuhn, nach-ruhl] / ˈnætʃ ər əl sɪˈlɛk ʃən, ˈnætʃ rəl /

noun

1. the process by which forms of life having traits that better enable them to adapt to specific environmental pressures, as predators, changes in climate, or competition for food or mates, will tend to survive and reproduce in greater numbers than others of their kind, thus ensuring the perpetuation of those favorable traits in succeeding generations.

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natural selection British  

noun

1. a process resulting in the survival of those individuals from a population of animals or plants that are best adapted to the prevailing environmental conditions. The survivors tend to produce more offspring than those less well adapted, so that the characteristics of the population change over time, thus accounting for the process of evolution

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natural selection Scientific  

1. The process by which organisms that are better suited to their environment than others produce more offspring. As a result of natural selection, the proportion of organisms in a species with characteristics that are adaptive to a given environment increases with each generation. Therefore, natural selection modifies the originally random variation of genetic traits in a species so that alleles that are beneficial for survival predominate, while alleles that are not beneficial decrease. Originally proposed by Charles Darwin, natural selection forms the basis of the process of evolution.

2. See Notes at adaptation evolution Compare artificial selection

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natural selection Cultural  

1. A process fundamental to evolution as described by Charles Darwin. By natural selection, any characteristic of an individual that allows it to survive to produce more offspring will eventually appear in every individual of the species, simply because those members will have more offspring.

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Discover More

The expression survival of the fittest was used to describe this process in the nineteenth century but is not favored by modern scientists.

Etymology

Origin of natural selection

First recorded in 1855–60

Compare meaning

How does natural-selection compare to similar and commonly confused words? Explore the most common comparisons:

• natural selection vs. artificial selection
• sexual selection vs. natural selection

Example Sentences

See Examples For:

natural selection

He argues that, as natural selection has shaped our brains and influenced our actions, the way we guide and govern behavior should be approached with our evolutionary roots in mind.

From The Wall Street Journal ● Jul. 24, 2026

Evolution by natural selection is such a familiar concept that it can be easy to forget it describes the present as well as the past.

From The Wall Street Journal ● Jul. 24, 2026

One influential idea is that natural selection becomes weaker later in life, allowing harmful biological processes to emerge with age because they have less impact on reproduction and survival earlier in life.

From Science Daily ● May 22, 2026

That was assumed to be the result of a natural selection.

From Barron's ● Feb. 26, 2026

Indeed, if you coupled the genesis of spontaneous mutants—the giant-leaved Oenothera, say—with natural selection, then Darwin’s relentless engine was automatically set in motion.

From "The Gene" by Siddhartha Mukherjee