types of natural selection

what does disruptive selection do?

create 2 new modal phenotypes in the extremes

explanation of directional selection

1. Selection pressure favours the extreme phenotype, they’re at a selective advantage and those displaying the mean are at a selective disadvantage

2. Mean phenotypes shift either left or right over generations

3. This reduces variation

4. range of phenotypes is narrower

explanation of stabilising selection

1. Selection pressure favours the mean phenotype, they’re at a selective advantage and those displaying the extreme are at a selective disadvantage

2. Mean phenotypes stay the same over many generations

3. This reduces variation

4. range of phenotypes is narrower

Explanation of disruptive selection

1. Selection pressure favours the extreme phenotype, they’re at a selective advantage and those displaying the mean are at a selective disadvantage

2. Mean phenotypes shift left AND right from one generation to the next

3. This increases variation

4. range of phenotypes is wider