genetic drift

American  

noun

1. random changes in the frequency of alleles in a gene pool, usually of small populations.

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genetic drift Scientific  

1. Variation in the frequency of a gene in a small isolated population, thought to be due to random chance rather than natural selection.

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genetic drift Cultural  

1. A term that describes the random fluctuations in a gene pool over time. In large populations, the effects of genetic drift are negligible. (Compare natural selection.)

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Etymology

Origin of genetic drift

First recorded in 1955–60

Compare meaning

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

• gene flow vs. genetic drift

Example Sentences

See Examples For:

genetic drift

Together, these genomic signals suggest that these leopards are small because they’ve adapted that way, and not only because of isolation or genetic drift.

From Science Daily ● Jun. 24, 2026

Its genetic drift is significantly different from BA.4 and BA.5, the variants last year's bivalent boosters were targeted against.

From Salon ● Sep. 12, 2023

One way to tell the difference is speed: Under extreme conditions, natural selection can make a mutation spread far faster than genetic drift can.

From New York Times ● Oct. 19, 2022

They think random genetic drift is driving some of the differences.

From Science Magazine ● Aug. 24, 2022

However, in all populations, mutation, natural selection, genetic drift, and migration act to change allele frequencies.

From Textbooks ● Apr. 25, 2013