Biology / Unit 8 Bio 1675 short lesson, about 20 seconds
Neutral, Beneficial, and Deleterious Mutations
Captions available
The idea
A mutation's effect on fitness falls into one of three categories: deleterious, reducing survival or reproduction; beneficial, improving it; or neutral, changing neither.
In practice
A point mutation in a non-coding region, per Unit 6's Bio 1297, changing fitness not at all is a neutral mutation.
Where people slip
Most new mutations are neutral or deleterious — beneficial is the least common outcome, not the default.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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