Biology / Unit 8 Bio 1757 short lesson, about 20 seconds
Genetic Drift
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The idea
Genetic drift is a random change in allele frequencies between generations, driven by chance rather than any effect on fitness.
In practice
An allele's frequency shifting because its carriers happened, by chance, to reproduce more, not from selective advantage, is genetic drift.
Where people slip
Genetic drift and natural selection can act on a population at once — one being present does not rule out the other.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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