Blog # 4 Describe the three types of selection: directional, stabilizing and disruptive and give an example of each in your own words

Directional selection is one extreme of the trait distribution experiences selection against it. The result is that the population's trait distribution shifts toward the other extreme.
In stabilizing selection, it is when selective pressures select against the two extremes of a trait, the population experiences stabilizing selection.
Disruptive selection is when selection pressures act against individuals in the middle of the trait distribution.


Example of directional: Breeding of the greyhound dog. Early breeders were interested in dog with the greatest speed. They carefully selected from a group of hounds those who ran the fastest. From their offspring, the greyhound breeders again selected those dogs who ran the fastest.
Example of stabilizing: The size of newborn human babies.
Example of disruptive: The evolution of Darwin's finches, the explanation being that each island applied different selection pressure on the same types of mainland finch, favouring slightly different bill shape.