Question

Selection can act in different ways. Match the type of selection with the correct description below.

1.The frequency of dominant and recessive homozygotes is high, with only a small     number of heterozygotes

2.Two extreme phenotypes related to eye size occur in high frequency in a population

3.The frequency of big-eyed individuals shifts to a higher frequency in the population

4.The mean value of a phenotype is maintained in a population across generations

Answer 1

1. Disruptive selection

2. Disruptive selection

3. Directional selection

4. Stabilizing selection

Natural selection, as propsed by Darwin in its Origin of Species, leads to the survival of the fittest.

Natural selection can affect the distribution of the phenotypes in distinct ways as shown above.

Directional selection: an extreme phenotype is preferred.

Stabilizing selection: an intermediate (or average) phenotype is selected.

Disruptive selection: both the extreme phenotypes are preferred.