genetic drift
What genetic drift means in Biology A-Level, as defined for AQA, OCR.
Definitions of genetic drift
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Reference: AQA
A change in allele frequency caused by chance rather than by selection, where only a sample of each generation's alleles is passed on.
The chance sampling error that shifts frequencies when only a few individuals reproduce, removed by a large population.
Changes allele frequencies by chance rather than by fitness, especially in small populations.
Topics that use genetic drift
- Evolution may lead to speciation (A-level only) (AQA A-Level)
- Populations (A-level only) (AQA A-Level)
- Patterns of inheritance (OCR A-Level)
Related terms
- continuous variation
- discontinuous variation
- gene flow
- random fertilisation
- Allele frequencies
- allele frequency change
- Alleles, genotypes and phenotypes
- allopatric speciation
Using genetic drift in the exam
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