5. types of natural selection Flashcards
1
Q
define directional selection
A
favours one extreme of characteristics, causing a shift in population curve
2
Q
define disruptive selection
A
favours both extremes, against the mean, causing a bimodal distribution
3
Q
define a stabilising selection
A
favours the mean of the distribution, as the extremes are at a selective disadvantage, bell shaped curve
4
Q
when does stabilising selection occur?
A
when the environment isnt changing
5
Q
when does directional selection occur?
A
when there is environmental change
